A Comprehensive Review of Skin Pharmacotherapy: NAPLEX Review

Glaucoma is a progressive eye condition that damages the optic nerve and can lead to vision loss, including reduced peripheral and central vision. A key characteristic of glaucoma is elevated intraocular pressure (IOP), which typically exceeds the normal range of 12–22 mmHg. This elevated pressure is a major risk factor, though glaucoma can also occur with normal IOP levels. Factors such as genetics, age, and certain medications can increase the risk of developing glaucoma. “The only sure way to diagnose glaucoma is with a complete eye exam. A glaucoma screening that only checks eye pressure is not enough to find glaucoma”(AAO). Left untreated, glaucoma can cause irreversible blindness, making early detection and treatment crucial. There are two main types of glaucoma: open-angle and angle-closure (or closed-angle). Open-angle glaucoma is the most common form and often develops gradually without symptoms, making regular eye exams vital for early diagnosis. In contrast, angle-closure glaucoma is a medical emergency caused by a sudden and severe increase in IOP. It presents with symptoms such as eye pain, headaches, and blurred vision, requiring immediate surgical intervention to prevent permanent vision loss. Regardless of the type, the primary goal of treatment is to lower IOP to preserve vision and prevent further optic nerve damage. Drug treatments for glaucoma work by either decreasing the production of aqueous humor, the fluid in the eye, or enhancing its outflow. Prostaglandin analogs are among the most effective and commonly prescribed drugs, reducing IOP by up to 30%. These medications, such as bimatoprost (Lumigan) and latanoprost (Xalatan), are safe, require only once-daily dosing, and are well-tolerated. However, they can cause side effects, including darkening of the iris, eyelash thickening, and changes to eyelid skin. Beta-blockers like timolol are another option, reducing IOP by about 22%. A beta-blocker is preferable if the pressure is high in only one eye only because the darkening of the iris and eyelash thickening seen with PG analogs is not desirable in only one eye” (UWorld RxPrep). Other drugs, including alpha-2 agonists and carbonic anhydrase inhibitors, can also help by reducing aqueous humor production, while combination therapies are available for patients who need more aggressive IOP control. Successful glaucoma treatment requires not only effective medications, but also proper patient adherence and eye drop application techniques. Patients should be educated on how to administer eye drops correctly to ensure maximum efficacy and to minimize potential side effects. Adherence to treatment is often challenging, especially for those with open-angle glaucoma, as the condition progresses silently without noticeable symptoms. Regular follow-ups, combined with patient education, are essential to maintaining long-term treatment success and preventing vision loss. Patients with glaucoma or at risk for the condition should also avoid certain medications that can increase IOP. These include anticholinergics (such as antihistamines and tricyclic antidepressants), decongestants like pseudoephedrine, steroid-containing eye drops, and specific systemic drugs like topiramate. Consulting a healthcare provider before using these medications is essential to prevent worsening of the condition. Glaucoma is a complex and potentially blinding disease, but early diagnosis and appropriate management can preserve vision and improve quality of life. By lowering IOP through medications or surgery and ensuring patient adherence to treatment regimens, the progression of this disease can often be slowed or halted. Ongoing education and regular monitoring are key components of effective glaucoma management.

https://www.aao.org/eye-health/diseases/what-is-glaucoma

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Minor wounds, inflammation, and rashes are common skin issues that vary in severity but require prompt and effective care to prevent complications. Minor wounds include cuts, scrapes, abrasions, burns and bites. Puncture wounds should be referred to a medical provider and it needs to be verified that the patient’s tetanus shot is up to date. This is important because “tetanus is a serious infection that can cause muscle stiffness and spasms, and even lead to death. It is caused by bacteria that live in the dirt” (UpToDate).  Chronic wounds like pressure ulcers require management by wound care providers. This care includes debridement in which contaminated tissue is removed to help enhance the healing process. The most common type of debridement is enzymatic debridement which is done with the application of collagenase ointment. Lacerations are different from cuts in that lacerations have ragged edges and has a potential for greater damage. After cleaning cuts and lacerations, if the bleeding does not stop, it is recommended to seek medical attention as the wound might require stiches. Tissue adhesive are used to create a polymer layer which binds the skin and keeps the wound protected and clean. Wound seal is a powder that is used over a bleeding would to help with scab formation and healing. Abrasions are minor injuries to the top layer of the skin and is treated by cleaning and applying antibiotics and a bandage.  occur when the skin’s protective barrier is broken. Immediate care involves cleaning. Bites from humans and animals are considered infectious and should be evaluated by a healthcare provider. Other minor harmless insect bites can be treated with a topical steroid or oral antihistamine to reduce itching. Burns can be categorized into three groups – first, second and third degree. First degree burns are red and painful with minor swelling. Second degree burns are thicker, produces blisters and are very painful. Third degree burns affect all the layers of the skin and it appears white or charred. OTC treatment of burns is acceptable “if the area is less than two inches in diameter and not located on the face over a major joint or on the feet or genitals” (UWorld RxPrep). OTC treatment includes placing the burn under cold running water for 5-20 minutes. Applying ice is not recommended a sit can further damage the skin. Ointments like Aquaphor should be applied and this can help protect the skin, retain moisture and reduce scarring risk. Silver sulfadiazine can be used topically to help reduce infection risk and promote healing in burns. This should not be used if the skin is broken or the patient has a sulfa allergy or G6PD deficiency. Topical antibiotics are to be applied after cleaning the affected area. After this, a small amount (about the surface area of the tip of a finger) is to be taken and applied to the affected area 1 to 3 times a day. The area should then be covered with a bandage if it is in an area that can be easily dirtied like a hand. Dressing are to be changed daily. Burns also require a moist environment for healing so it important to ensure that the burn is treated with an ointment and bandage designed for burns to promote healing.

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https://www.uptodate.com/contents/taking-care-of-cuts-scrapes-and-puncture-wounds-the-basics/print

Pinworm, lice, and scabies are parasitic infestations that commonly affect humans. Pinworm infection is caused by Enterobius vermicularis, a tiny intestinal worm that spreads through the fecal-oral route. It is most common in children, presenting as intense anal itching, particularly at night. Patients are diagnosed with pinworm through the process known as the tape test. The tape test is when a piece of tape is stuck around anus in the morning prior to defecating. The tape is them removed and brought to the healthcare provider who then observes the tape for pinworm eggs. It can take up to 3 tape tests to identify eggs. Treatment includes oral antiparasitic medications such as mebendazole, albendazole, or pyrantel pamoate. Pyrantel causes headaches and dizziness and are given as a single dose. Another dose is given 2 weeks later to prevent reinfection. Mebendazole and albendazole cause headache and nausea and are hepatotoxic. Albendazole is also to be taken with a high fat meal to help with absorption. Pinworms are difficult to treat as they are often resistant and have a high rate of reinfection. All household members are to be treated simultaneously to prevent reinfection. Hygiene measures, such as washing bedding and clothes in hot water, are essential.

Lice, including head lice, Pediculus humanus capitis, are blood-feeding parasites that cause itching and irritation. They spread through direct contact or shared personal items like combs and hats. It “occurs most commonly in elementary school age children” (UWorld RxPrep). Treatment for lice includes OTC treatment such as Nix which comes as a lotion, shampoo and spray, and are generally first line. Over time pyrethrin has become less effect do it resistance. Nix should also be avoided in patients with a chrysanthemum or ragweed allergy. Topical ivermectin (Sklice) is approved to treat head lice. Oral ivermectin can also be prescribed for head lice but the patient has to weigh at least 15 kg. Lidaine 1% shampoo is no longer available as it was removed from the market due to nephrotoxicity. After treatment, it is important to use a nit comb to remove nits and lice every 2-3 days. The scalp should be inspected every 2-3 weeks to make sure all the nits and lice are gone. Most products should be left in the hair for 10 minutes before rinsing to be effective. Similar to the precautionary measures taken with pinworm, patients who have lice should wash their clothing and bedding in hot water followed by a hot dryer. Carpets should be vacuumed, and combs and brushes should be soaked in hot water for 10 minutes. Scabies, caused by the mite Sarcoptes scabiei, leads to intense itching and a rash from the mites burrowing under the skin. “Common areas on body where symptoms occur include between fingers, in the skin folds of the wrist, elbow, knee, or armpit, and on the penis, nipples, waist, buttocks, and shoulder blades.” (CDC). Prescription treatments such as permethrin cream 5% or oral ivermectin are required to eliminate the infestation.

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https://www.cdc.gov/scabies/about/index.html

Cold sores, diaper rash, and hemorrhoids are common conditions that can cause discomfort but are generally manageable with appropriate treatment.

Cold sores, are caused by the herpes simplex virus (HSV), typically HSV-1. The way this virus spreads is through active lesions that transmit the virus to other individuals during kissing or sharing drinks. Before a sore appears the patient would experience prodromal symptoms like tingling, itching, soreness. Most patients experience these sores in the same location. The most common spot for cold sores to appear is the junction between the upper and lower lip.  Sores outbreaks can be triggered by stress, illness, sunlight, or hormonal changes, cold sores often follow a predictable course. The initial tingling or burning sensation is followed by blister formation, rupture, and healing over 7–10 days. Treatment includes antiviral medications like acyclovir, or over-the-counter topical creams containing docosanol, which can reduce the duration and severity of symptoms. The prodromal period is the optimal time to start treatment to reduce blister duration. If recurrences are frequent, chronic suppression treatment can be considered. Lysine is a natural product that is commonly used for cold sore prevention. Preventative measures include using sunscreen, managing stress, and avoiding direct contact with others during outbreaks.

Diaper rash, or diaper dermatitis, is a common condition in infants and toddlers caused by prolonged exposure to moisture, friction, and irritants such as urine or feces. It appears as red, inflamed skin in the diaper area and makes the area susceptible to fungal or bacterial infections. Prevention involves frequent diaper changes, gentle cleansing, and using barrier creams containing zinc oxide or petroleum jelly. In cases of secondary infections, antifungal creams like clotrimazole, miconazole. and nystatin may be used. Hydrocortisone can be applied twice a daiy but not for more than several days at a time. Parents are advised to let the skin breathe by allowing diaper-free time and avoiding harsh wipes or soaps.

Hemorrhoids are swollen veins in the rectum or anus, often caused by increased pressure due to straining during bowel movements. “Hemorrhoids can develop inside the rectum, called internal hemorrhoids. They also can develop under the skin around the anus, called external hemorrhoids” (Mayo Clinic) The rectal tissue has a rich blood vessel supply, and this makes the area susceptible to swelling or engorgement. Patients with hemorrhoids experience symptoms such as pain, itching, swelling, and bleeding during defecation. Treatment focuses on relieving symptoms and preventing recurrence. Over-the-counter options include hydrocortisone, witch hazel pads, and stool softeners to reduce strain. Hydrocortisone comes as anal suppositories can as various topicals like creams and wipes. This helps as it reduces inflammation and itching. Witch Hazel is a mild astringent that helps relieve mild itching. Phenylephrine can also be used, and this helps reduce the size of the hemorrhoids which reduces the burning and itching.  Ointments are to be applied once rectum is cleaned and gently dried. It can be applied up to 5 times daily. The way to use suppositories are to “separate the foil tabs and slowly peel apart, remove from the wrapper, insert into the rectum up to 4 times daily, especially at night after a bowel movement” (UWorld RxPrep). Lifestyle changes like increasing dietary fiber and fluid intake, regular exercise, and avoiding prolonged sitting can also help.

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https://www.mayoclinic.org/diseases-conditions/hemorrhoids/symptoms-causes/syc-20360268

Dandruff and alopecia are two prevalent scalp conditions that can greatly impact a patient’s quality of life. Understanding their characteristics and available treatments is essential for effective management.

Dandruff is a common scalp disorder characterized by the shedding of white or gray flakes of dead skin. It is often accompanied by itching and irritation. The primary cause of dandruff is seborrheic dermatitis, a condition that leads to oily, irritated skin and the proliferation of yeast on the scalp. Other contributing factors include dry skin, sensitivity to hair care products, and certain skin conditions like psoriasis and eczema. Treatment for dandruff focuses on reducing scalp inflammation and controlling the yeast population. Over-the-counter shampoos containing active ingredients such as zinc pyrithione (Head and Shoulders), selenium sulfide (Selsun), or ketoconazole (Nizoral) are commonly recommended. Zinc pyrithione and selenium sulfide possess antifungal properties that target yeast. Ketoconazole is an imidazole antifungal and is effective against a broad spectrum of fungi and is often used in more persistent cases. Regular use of these shampoos can help manage symptoms. An inexpensive OTC dandruff shampoo can be tried first. If this is ineffective, ketoconazole antifungal shampoo can be used (UWorld RxPrep).

Alopecia, or hair loss, encompasses various conditions leading to the loss of hair from the scalp or other parts of the body. The most common form is androgenetic alopecia, also known as male or female pattern baldness, which is influenced by genetic and hormonal factors. Hormonal changes in women that can result in hair loss are usually associated with pregnancy, childbirth, or menopause. (UWorld RxPrep) Other types include alopecia areata, an autoimmune disorder resulting in patchy hair loss, and a temporary shedding of hair often triggered by stress, illness, or hormonal changes. “Alopecia areata is a surprisingly common disease. About 2% of people across the world will experience alopecia areata at some point. They either currently have alopecia areata, they have had it, or they will develop it. The disease affects as many as 7 million people in the U.S. alone” (National Alopecia Areata Association). Hypothyroidism, chemotherapeutics, valproate, lamotrigine, and tacrolimus can cause hair loss. For androgenetic alopecia, topical minoxidil is widely used to stimulate hair growth and slow hair loss. Minoxidil increases blood flow to hair follicles, promoting growth and enlarging follicle size. Oral finasteride, a 5-alpha-reductase inhibitor, is another option for men. It works by reducing dihydrotestosterone (DHT) levels, a hormone linked to hair follicle miniaturization. For women, hormonal therapies such as oral contraceptives or anti-androgens like spironolactone may be considered, especially when hair loss is associated with hormonal imbalances. Addressing the underlying cause for hair loss such as managing stress, correcting nutritional deficiencies, or treating medical conditions is crucial, as hair typically regrows once the trigger is resolved. Hair transplant surgery is another option for individuals with significant hair loss, which is the transplantation of hair follicles from one part of the body to the balding areas. It's important to note that while these treatments can be effective, results vary among patients, and some may experience side effects. Consulting with a healthcare provider or dermatologist is essential to determine the most appropriate treatment plan based on the specific type and cause of dandruff or alopecia. Additionally, maintaining a healthy lifestyle, managing stress, and following a proper hair care routine can support treatment outcomes and overall scalp health.

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https://www.naaf.org/alopecia-areata/

Fungal infections can affect various parts of the body like the skin and nails. Common types include athlete's foot, jock itch, ringworm, cutaneous candida infections, onychomycosis, and vaginal yeast infections. Understanding their characteristics and treatment options is essential for effective management.

Athlete's Foot (Tinea Pedis): This fungal infection primarily affects the feet, especially the areas between the toes. It manifests as itching, redness, scaling, and sometimes with mild burning. The condition thrives in warm, moist environments, making communal areas like locker rooms and swimming pools common sources of infection. Treatment typically involves using topical antifungal agents such as clotrimazole or terbinafine for two to four weeks. Preventive measures include keeping the feet dry, wearing breathable footwear, and avoiding walking barefoot in public areas.

Jock Itch (Tinea Cruris): This infection “affects the genitals, innter thighs and buttocks. The rash is red, itchy, and can be ring-shaped” (UWorld RxPrep). It is more common in males and can be exacerbated by tight clothing and excessive sweating. Topical cream antifungals such as miconazole or clotrimazole are used to treat jock itch. Maintaining proper hygiene, keeping the area dry, wearing loose-fitting clothing, and changing underwear daily can help prevent recurrence.

Ringworm (Tinea Corporis): Despite its name, ringworm is a fungal infection and not a worm, that causes a characteristic circular, red, flat sore with a clear center and raised edges. It can appear on various parts of the body and is highly contagious, spreading through direct contact with infected individuals or animals. Topical antifungals like clotrimazole or terbinafine are effective treatments, applied for at least two weeks. “Ringworm is difficult to prevent. The fungus that causes it is common, and the condition is contagious even before symptoms appear,” (Mayo Clinic) so taking key steps like maintaining good hygiene and avoiding sharing personal items are preventive strategies as it can be spread easily person to person or by contact with infected animals.

Cutaneous Candida Infections: Candida species can infect skin folds, leading to red, itchy rashes. These infections are common in areas prone to moisture, such as under the breasts, armpits, and groin. Patients who are obese are at risk because they have more skin folds. Vaginal yeast infections are also caused by candida. These infections cause burning, itching, and a thick white discharge. Treatment for yeast infections include antifungal cream, suppositories containing miconazole or clotrimazole, and fluconazole. Topical antifungals like nystatin or clotrimazole are typically used to treat cutaneous candida infections. Keeping the affected areas dry and wearing loose clothing can aid in prevention of these infections.

Onychomycosis: This refers to fungal infections of the nails, caused by tinea unguium, leads to pain, discomfort, and disfigured nails. Topical treatment can be done for mild cases as they are not potent enough to cure most infections. Oral antifungals such as terbinafine or itraconazole are commonly prescribed. Other antifungals that can be used are fluconazole, posaconazole, and griseofulvin. A 20% potassium hydroxide smear is essential for diagnosis because this can be mistaken for other conditions.

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https://www.mayoclinic.org/diseases-conditions/ringworm-body/symptoms-causes/syc-20353780

Acne

"Acne is a common skin condition that happens when hair follicles under the skin become clogged" (NIAMS). They can be clogged with oil, dead skin cells, and bacteria, leading to pimples, blackheads, whiteheads, and, in more severe cases, cysts and nodules. This condition typically appears on the face, back, chest, and shoulders, where sebaceous (oil) glands are highly concentrated. Contributing factors include excess oil production, bacteria, and inflammation. Hormonal changes during puberty, pregnancy, or menstruation often lead to increased sebum production, which can clog pores and cause breakouts. Genetics also plays a role, making some individuals more prone to acne. Though diet and stress aren’t direct causes, they can worsen acne. Certain high-glycemic foods and dairy products are linked to breakouts, and stress may trigger inflammation, intensifying acne symptoms.

Acne manifests in several forms, including whiteheads, blackheads, papules, pustules, nodules, and cysts, each requiring different treatment approaches. For mild to moderate cases, over-the-counter products containing benzoyl peroxide, salicylic acid, or retinoids help by targeting bacteria, exfoliating, or promoting cell turnover to prevent clogged pores. Persistent cases may need prescription-strength treatments like stronger retinoids or topical antibiotics. For moderate to severe acne, dermatologists may prescribe oral medications, such as antibiotics or hormonal treatments, which are especially effective for women with hormonally triggered acne. In more severe cases, isotretinoin (commonly known as Accutane) may be recommended. This potent medication can significantly reduce acne but requires close medical supervision due to potential side effects. Isotretinoin is highly teratogenic and requires iPledge REMS monitoring.

“Benzoyl peroxide is an effective OTC medication and is recommended for most patients with acne. It is also available by prescription, including in combinations with hydrocortisone, adapalene, or antibiotics.” (UWorld RxPrep) Typically it can be started at a strength of 2.5-5% as it is generally adequate and less irritating and is found in many OTC products like Benzac, PanOxyl, and Clearasil.  Salicylic acid is also found in many OTC products and helpful for acne. Retinoids are vitamin D derivatives and work by reducing cohesion of follicular epithelial cells and that helps with increasing turnover and unblocking pores to prevent acne. Retinoids as mentioned earlier are highly teratogenic which means that it is avoided in pregnancy and breastfeeding. They are to be used nightly followed by a moisturizer and sunscreen every morning. They take 4-12 weeks to work and can cause the acne to get worse before it gets better. Some women find benefit using oral contraceptive pills especially if the acne occurs around their menstrual cycle. Spironolactone can also be used to acne in some females.

Some other ways to treat acne include chemical peels, laser and light therapies, and cortisone injections, which can be helpful for deep cystic acne. Maintaining a gentle skincare routine, avoiding harsh scrubs, and refraining from picking at acne can prevent scarring and irritation. It can be helpful to wash acne prone skin twice a day and to use skin care products that are non-oily and water based. Also being mindful of touching the face and showering after strenuous activity can help with preventing bacteria buildup on the face which can help prevent acne formation. Some find that dietary adjustments, like reducing sugar and dairy intake, help manage acne. Additionally, managing stress through exercise, meditation, or better sleep can reduce flare ups in some individuals.

https://www.niams.nih.gov/health-topics/acne

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Skin Cancer: Melanoma Review & Patient Information for Prevention

                   Skin Cancer is a major health problem in the USA, with 1 in 5 Americans estimated to develop skin cancer in their lifetime. Skin cancer when caught early can be treated. The two types of skin cancer are nonmelanoma skin cancers and melanoma. Prevention and screening have a major impact on detecting cancer early and treating it. 

                   Most commonly, melanomas occur from DNA damage, due to UV radiation, which leads to cellular mutations that transform the cell and result in uncontrolled proliferation and the formation of tumors (1). Primary melanoma can occur in any area of the body with melanocytes. Melanoma cells can evade the immune system by exploiting immune checkpoints (1). Melanomas can occur without nonchronic sun damage due to the activation of different pathway mutations. 

                   There are both patient-related risk factors and external risk factors for melanoma. Some patient-related risk factors are age over 15 years, history of cutaneous melanoma, sunburns easily, or tans rarely. Some external risk factors are history of sunburn and recreational sun exposure. 

                    As skin cancer is a major health problem in the USA, the surgeon general in 2014 released a call to action to prevent skin cancer. This call to action for skin cancer prevention included: increase opportunities for sunprotection in outdoor settings; provide individuals with the information they need to make informed, healthy choices about UV radiation exposure; promote policies to advance the national goal of preventing skin cancer; reduce harms from indoor tanning; and strength research, surveillance, monitoring, and evaluation related to skin cancer prevention (1).  By avoiding UVA and UVB exposure, one can protect themselves from the most preventable cause of melanoma. Individuals should avoid the sun during peak hours of sun intensity (10am-4pm), seek shade when outdoors, and use protective clothing when out in the sun. In addition to these measures, patients should regularly use sunscreen to decrease UV exposure. Patients should be counseled on how to appropriately use broad spectrum sunscreen with both UVA and UVB protection with an SPF of 15 or higher. Patients should be told that sunscreen should be applied 30 minutes before going into the sun and reapplied every 2 hours after swimming or after sweating heavily (1).  

                  In addition to prevention measures, patients should be informed on how to conduct a self skin examination. Early detection is key to improved survival rates for melanoma. The American Cancer Society and The American Academy of Dermatology both have great guidelines on how to perform a self examination. Generally, a self skin examination should be done after a shower or bath for ease, one should examine their body in a full length mirror with their arms raised. Next, one should look at their underarms, forearms, and palms. After, one should look at their legs, between their toes, and the soles of their feet. After this, one should use a hand mirror to examine their neck and scalp and to check their back and buttocks (2). These steps are a rough generalization of how to conduct a self skin examination, both resources will be linked for further in depth instructions. 

                 The ABCDE’s of Melanoma is another important resource. When inspecting moles or pigmented spots, patients should look for asymmetry, borders, color, diameter, and evolving (3). 

                 In summary, prevention of skin cancer is important and should be taught to all of our patients. 

Resources

(1): O’Bryant C.L., & Davis C.M. Melanoma. DiPiro J.T., & Yee G.C., & Haines S.T., & Nolin T.D., & Ellingrod V.L., & Posey L(Eds.), [publicationyear2] DiPiro’s Pharmacotherapy: A Pathophysiologic Approach, 12th Edition. McGraw Hill. https://accesspharmacy-mhmedical-com.jerome.stjohns.edu/content.aspx?bookid=3097&sectionid=271456764

(2): https://www.aad.org/public/diseases/skin-cancer/find/check-skin

(3): https://www.aad.org/public/diseases/skin-cancer/find/at-risk/abcdes

Pharmacotherapy Summary for all NAPLEX Skin Conditions

There are little data on the prevalence of dermatological disorders in various populations. Estimates and extrapolation of survey results reveal that anywhere from 12% to 31% of visits to physicians involve dermatological problems, depending on location, age, ethnicity, and type of medical provider. Pharmacists are routinely asked for assistance with the diagnosis and treatment of many common skin conditions. Therefore, it is important for pharmacists to recognize common skin disorders, so they can make appropriate recommendations about self-care and referral.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 566-581

2) Common Skin Disorders. In: Herrier RN, Apgar DA, Boyce RW, Foster SL. eds.Patient Assessment in Pharmacy. McGraw Hill; 2015. Accessed April 05, 2022. https://accesspharmacy.mhmedical.com/content.aspx?bookid=1074&sectionid=62364288

Fungal Infections: Toenail & Fingernail

Onychomycosis, a fungal infection of the nail, is often caused by tinea unguium. Onychomycosis can cause pain, discomfort, and disfigurement, and can lead to physical limitations (difficulty walking, standing, etc.) Discoloration and disfigurement can lead to self-esteem and psychological issues as well - this is a common theme throughout our coverage of skin conditions. Onychomycosis is treated with monotherapy of topical drugs in mild cases and for patients who can not tolerate systemic therapy. Otherwise, topical drugs are used in combination with systemic treatments or alone as prophylaxis. Topical drugs alone are NOT potent enough to cure most infections.

Itraconazole and terbinafine are approved for this use and most commonly used; fluconazole and posaconazole are used off-label. Griseofulvin is rarely ever used in treatment of fungal nail infections. Pulse therapy (intermittent) can be used to reduce costs and possibly toxicity, but may not be as effective. A 20% KOH smear is essential for diagnosis, as other conditions can produce similar presentations.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 573.

Fungal Infections: Skin

Athlete’s foot, also known as tinea pedis, is a fungal infection of the foot caused by various fungi, commonly trichophyton rubrum. Symptoms of tinea pedis include feet itching, peeling, redness, mild burning, and sometimes sores. This is a common infection, particularly among those using public pools, showers, and locker rooms. For these reasons, suggesting shoes in these situations may help prevent recurrent infections. Diagnosis of tinea pedis is usually symptom-based, but if the underlying cause of infection is unclear, the skin can be scraped off and viewed under a microscope. Other conditions which may cause redness and itching of the feet are psoriasis or eczema. Treatment of tinea pedis is topical antifungal medications, except in severe cases.

**** itch, or tinea cruris, is a fungal infection affecting the ********, inner thighs, and buttocks. The rash appears red, is itchy, and can be ring-shaped. **** itch is not very contagious, but can be spread person-to-person with close contact. Important counseling points for tinea cruris include keeping the area dry by using a clean towel after showering. Antifungal cream preparations tend to work best for **** itch.

Ringworm, or tinea corporis, is not a worm, but a skin fungal infection. Ringworm can appear anywhere on the body and typically looks like circular, red, flat sores (one or more, may overlap) usually with dry, scaly skin. Occasionally the ring-like presentation is not present - just itchy, red skin. The outer part of the sore can be raised while the skin in the middle of the lesion appears normal. Ringworm can spread from person to person or by contact with infected animals. Most cases are treated topically. Tinea capitis is ringworm on the scalp - it affects mostly young children in crowded, low income situations. Tinea capitis requires systemic antifungal therapy, with the same drugs used for onychomycosis.

Topical Cutaneous candida infections cause red, itchy rashes, most commonly in the groin, armpits, or anywhere the skin folds. These are more likely in obese persons because they tend to have more folds in the skin. The infection can be present in unusual places such as under the *******, if the skin is moist. Diabetes is also a known risk factor for developing cutaneous candida infections. Occasionally, fungal infections appear in the corner of the nails (on the skin, not in the nail bed). If this is a suspected bacterial infection, OTC antibiotic topicals or mupirocin can be used. Candida can also cause diaper rash in infants.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 572.

Hyperhidrosis: NAPLEX Review

Hyperhidrosis, or excessive sweating, is a common skin condition which is associated with increased social stress and comorbid psychological issues. Diagnosis of hyperhidrosis is based on physical exam and thorough medical history. Treatment of hyperhidrosis depends on the severity of sweating as well as the location of sweating (underarms, hands, feet, etc). RxPrep discusses hyperhidrosis very briefly, so in addition to this review, I will be posting a more in-depth look into the psychosocial implications of hyperhidrosis and the effect it may have on a patient’s quality of life. Current FDA-approved treatments for hyperhidrosis include Qbrexa (glycopyrronium), a product available in single-use cloth wipes to limit sweating under the arms. Botox injections are also an FDA-approved treatment for hyperhidrosis of the underarms.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 571.

Eczema (Atopic Dermatitis): NAPLEX Review

“Eczema” or atopic dermatitis, is a general term for many types of skin inflammation. Eczema is most commonly seen in children and infants, but it can occur at any age. Eczema presents dermatologically as a skin rash, which becomes crusty and scaly. The rash is red, itchy, dry, and sore - blisters may or may not develop. Common affected areas include the elbows, behind the knees/ears, face (often on the cheeks), buttocks, hands, and feet. It is important to note that certain products or environmental conditions can trigger eczema, such as allergens (in soaps, perfumes, etc), environmental irritants (pollen), stress, or changes in the weather.

Hydration is essential to reduce severity of atopic dermatitis - patients should be advised to use unscented moisturizers such as CeraVe or Eucerin, and to maintain adequate humidity in the home (which can be particularly difficult in the winter months). If necessary, pharmacological treatments can include topical steroids, short courses of oral steroids, antihistamines for itching, and finally immunosuppressant calcineurin inhibitors (if topical steroids with hydration are not adequate). In severe, refractory cases of atopic dermatitis, oral immunosuppressants such as cyclosporine and MTX, or monoclonal antibody drugs can be used. Dupilumab (Dupixent) is an FDA-approved monoclonal antibody for the treatment of moderate to severe eczema. Dupixent is administered as a biweekly subcutaneous injection; however, there are other drugs used for eczema off-label.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 571.

Alopecia: NAPLEX Review

Alopecia, or hair loss, is something that commonly happens as people age, but also can occur due to hormonal factors, medical conditions, and medications. The most common cause of hair loss is hereditary male-pattern baldness, and less common is female-pattern baldness. Hormonal changes in women that can result in hair loss are usually associated with pregnancy, childbirth, or menopause (during pregnancy, “baby hairs” tend to break at the forehead, and during menopause hair tends to thin). Medical conditions that can cause hair loss include hypothyroidism, alopecia areata (an autoimmune disorder - which I will be covering later on), scalp infections, and some other conditions such as lupus. Drugs that can cause alopecia include various chemotherapeutic agents (hair cells rapidly divide and are greatly affected by chemotherapy), valproate, spironolactone, heparin, warfarin, clomiphene, hydroxychloroquine, interferons, lithium, some times of oral contraceptives (levonorgestrel), and procainamide. Disorders such as zinc deficiency or vitamin D deficiency can also contribute to hair loss. Medications that treat alopecia work modestly - many people will end up seeking surgical intervention, such as hair transplants and others. Hair loss can be a regular part of the aging process, but when alopecia affects younger individuals, it often can impact their self confidence and quality of life. One major issue with all the therapeutic options we have for alopecia is that none of them are a permanent solution - all medications for alopecia must be used consistently to maintain hair growth.

Resources:

1) RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 570.

Pathophysiology and Pharmacotherapy of Dandruff

Seborrheic dermatitis is a common, chronic, relapsing form of eczema affecting sebaceous glands present on the scalp. Seborrheic dermatitis can be either inflammatory or noninflammatory - non inflammatory seborrheic dermatitis is the condition commonly referred to as “dandruff”. Dandruff affects children and adults alike, but the prevalence is greatest in young adults and in older people. Dandruff is more common among males vs. females. Infantile seborrheic dermatitis affects babies under the age of 3 months old, and is usually self-limiting, resolving by 6-12 months old. Dandruff presents as bran-like scaly patches scattered within hair-bearing areas of the scalp. Along with itchiness and discomfort, patients may also experience psychosocial effects of dandruff, particularly in young adulthood.

The cause of dandruff is not entirely understood, but the most acceptable culprit is an overgrowth of various species of Malassezia, a commensal, non-pathogenic yeast found on the skin. The issue with proliferation of Malassezia is that its metabolites, such as oleic acid and indole-3-carbaldehyde, may cause an inflammatory reaction. Presentation and likelihood of dandruff may differ by person due to differences in skin barrier lipid content. Some risk factors that contribute to development of dandruff are oily skin (a.k.a seborrhea), family history of dandruff or psoriasis, immunosuppression due to drugs or diseases, neurological and psychiatric diseases (Parkinson’s, TD, epilepsy, spinal cord injury, Down’s Syndrome), treatment for psoriasis with psoralen and PUVA therapy, as well as increased stress or lack of sleep.

Adults with dandruff present with affected areas on the scalp, face, and/or upper trunk. Typical features include winter flare-ups, minimal itching, combination oily and dry mid-****** skin, diffuse scale in the scalp, blepharitis, salmon-colored scaly patches in skin folds on both sides of the face, rash in the armpits, under the *******, in groin folds, and genital creases, as well as superficial folliculitis on the cheeks and upper trunk.

There are several options for the treatment of dandruff in adult patients. A store-bought, inexpensive dandruff shampoo can be tried first, and if ineffective, ketoconazole antifungal shampoo can be used. Some of the OTC options include Selsun Blue (active ingredient: selenium sulfide) and Head and Shoulders (active ingredient: zinc pyrithione). Nizoral A-D is an OTC option containing 1% ketoconazole, whereas the prescription strength ketoconazole cream/gel/foam is 2%. Other treatment options include topical steroids to reduce itching - should be applied daily for a few days every so often. Calcineurin inhibitors such as tacrolimus can be used as steroid alternatives. Coal tar cream can be applied to scaling areas and removed several hours later by shampooing. Combination therapy is often advisable - one product alone may not be sufficient for controlling moderate-severe dandruff.

Resources:

1. Oakley A. Seborrhoeic dermatitis. DermNetNZ. https://dermnetnz.org/topics/seborrhoeic-dermatitis/. Published 1997. Latest update by Dr Jannet Gomez, October 2017.

2. RxPrep NAPLEX Review 2021. Chapter 39: Common Skin Conditions. Page 569.

Drug-Induced Skin Reactions

The various types of drug-induced skin reactions can be classified as follows: erythematous reactions, angioedema/anaphylaxis, fixed drug eruptions, drug hypersensitivity syndrome, erythema nodosum, Steven-Johnson Syndrome (SJS), Toxic epidermal necrolysis syndrome (TENS), drug induced pigmentation/photosensitivity, and acneiform eruptions. The following will summarize these reactions (with photos), and describe in greater depth the causative agents and clinical presentations of each.

1. Erythematous Reactions

Clinical Presentation: These reactions are the most common ADRs involving the skin. This eruption is considered a type IV delayed cell-mediated hypersensitivity reaction. The eruption typically occurs 4 to 14 days after the causative drug is initiated; however, the reaction may occur 1 to 2 days after discontinuation of the drug. Upon a second exposure, the eruption may occur more rapidly. Lesions are symmetric erythematous macules or papules, which may be pruritic and usually develop on the trunk or upper extremities before progressing. Patients may experience a low-grade fever.

Causative Agents: penicillins, cephalosporins, sulfonamides, anticonvulsants, and allopurinol

Treatment: Primary treatment involves discontinuing the causative agent; however, if the drug is required for essential therapy, consideration may be given to continuation of the agent unless symptoms associated with the eruption suggest a more serious reaction. Topical corticosteroids, systemic corticosteroids, or antipruritic agents may also be considered. The eruption generally resolves within 7 to 14 days after the causative agent is discontinued.

2. Anaphylaxis: Angioedema, Urticaria

Clinical Presentation: Urticaria (hives) is a common, acute, transient reaction sometimes referred to as the cutaneous expression of anaphylaxis. It is characterized by pruritic monomorphic erythematous and edematous papules and plaques. The onset of symptoms is rapid, sometimes within minutes, and the papules and plaques last from a few hours to 24 hours. New lesions, however, may continually develop. In contrast, angioedema is defined by involvement of dermal and subcutaneous tissues and is described as pale or pink swelling that affects the face, buccal mucosa, tongue, larynx, and pharynx. Anaphylaxis may complicate urticaria and angioedema and may involve additional body systems, leading to shock and death. Urticaria, angioedema, and anaphylaxis are a consequence of either an immunoglobulin E (IgE)–mediated type 1 hypersensitivity reaction or an anaphylactoid mechanism involving histamine or other inflammatory mediators.

Causative Agents: ACEIs (within the first several months to 3 years) are notorious for causing angioedema. Examples of anaphylactoid reactions include responses to radiocontrast media, opiate-induced urticaria, and vancomycin-induced red man syndrome

Treatment: Management of this reaction consists of discontinuing the causative agent. Histamine receptor (H1) blockers, systemic corticosteroids, and epinephrine may also be required acutely.

3. Fixed Drug Eruption

Clinical Presentation: These eruptions present as pruritic, red, raised lesions that may blister or develop into plaques. A burning or stinging sensation may also be noted. Lesions typically develop in minutes to days of drug initiation and typically resolve within days; however, hyperpigmentation may remain for months. The lesions may develop anywhere on the body and may include the mucous membranes. When the causative agent is readministered, the lesions recur in the same area as the primary eruption.

Causative Agents: Any drug can cause a fixed drug eruption, but most notably seen with antimicrobial agents (tetracyclines, sulfonamides, metronidazole, nystatin), anti-inflammatory drugs (salicylates, NSAIDs), barbiturates, and oral contraceptives.

Treatment: typically resolves within days of d/c the causative drug

4. Erythema Nodosum Eruption

Clinical Presentation: A delayed-type hypersensitivity reaction that most often presents as erythematous, tender nodules on the shins and knees. These lesions are irregularly shaped and painful when palpated. Erythema Nodosum Eruptions are most common in women between 20-40 years old.

Causative Agents: oral contraceptives, sulfonamides, analgesics/NSAIDS, potassium iodide, phenytoin.

Treatment: usually self-limiting and resolves slowly over several weeks after d/c the offending agent.

5. Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis Syndrome (TENS)

Clinical Presentation: SJS and TENS are marked by large, painful blisters. They can also cause large areas of the top layer of your skin to come off, leaving raw, open sores. SJS involves less than 10 percent of the body, while TENS involves more than 30% of the body surface area. Symptoms are very acute, and begin within 4 weeks of drug exposure. Symptoms have also been documented to occur days after drug withdrawal. The eruption occurs even more rapidly when the causative agent is rechallenged. Initial symptoms include a prodromal phase of fever, sore throat, and stinging eyes. The skin blisters and mucous erosions occur 1 to 2 days later, with extensive epidermal detachment and sloughing. The rash may cover the entire body. Initially, the lesions are irregularly shaped, erythematous, purpuric macules that progressively coalesce. Necrotic epidermis detachment occurs. The mucous membranes (buccal, ocular, nasal, and genital) are affected in at least 85% of patients. Additionally, epithelium of the gastrointestinal and respiratory tracts may be involved. Patients may also have increased hepatic enzymes and leukopenia; however, the syndromes are not typically associated with eosinophilia. A marked loss of fluids, a drop in blood pressure, electrolyte disturbances, and infection may occur. SJS is fatal in 5% to 10% of patients and TEN is fatal in >30% of patients.

Causative Agents: long-acting sulfonamides, allopurinol, carbamazepine, fluoroquinolones, hydantoin, phenylbutazone, piroxicam, and others.

Treatments: Discontinuation of the causative agent is vital. Treatment is symptomatic and supportive. No other treatments are universally accepted, as the use of corticosteroids and other therapies is controversial.

6. Drug-Induced Hyperpigmentation/Photosensitivity

Clinical Presentation: Photosensitivity reactions may manifest as either a photo-allergic or phototoxic reaction. Some drugs are capable of producing both types of reactions. Phototoxic reactions are common and often predictable. Drugs that induce a phototoxic reaction absorb ultraviolet A (UVA) light. Phototoxicity is characterized by the rapid onset of a burning sensation. Clinically, patients present with an exaggerated sunburn, followed by hyperpigmentation. This reaction occurs only on sun-exposed skin. Less common clinical forms of the reaction are photo-onycholysis (phototoxicity involving the nails) and pseudoporphyria (a bullous photosensitivity disorder). Photoallergy is less common than phototoxicity and is a result of cell-mediated hypersensitivity. Photoallergy occurs from UVA transformation of drugs into allergens. This reaction may involve exposed skin and skin that is not exposed to the sun. Unlike the more immediate phototoxic reaction, photoallergy may not present until 24 to 72 hours post sun exposure. A photoallergy clinically appears as an acute, subacute, or chronic dermatitis.

Causative Agents: antibiotics (tetracyclines, fluoroquinolones, sulfonamides), TCAs, hydrochlorothiazide, beta blockers, amiodarone, sulfonylureas, sunscreens containing PABA, oral contraceptives, phenothiazine antipsychotics, and photosensitizing agents.

Treatment: Reduce the dose of the suspected agent. If dose reduction is not effective, recommend systemic corticosteroids or topical antihistamines. For a photoallergic reaction, administer antihistamine + corticosteroids. Topical corticosteroids and/or oral NSAIDs can also be used for pain and inflammation. Use of cold compresses also can provide pain relief to affected areas.

Resources:

1. Clinard V, Smith J. Drug-Induced Skin Disorders. US Pharmacist. https://www.uspharmacist.com/article/drug-induced-skin-disorders. Published 04/23/2012.

2. Moyer N. How to Identify and Treat a Drug Rash. Healthline. https://www.healthline.com/health/drug-rash. Published 02/12/2019.

Treatment of Acne

There are a variety of elements that contribute to the formation of acne, including bacterial presence, sebum, diet, and age. Androgens are the male sex hormones, and the primary determinant of acne development, especially in pubescent teens. Formerly known as P. acnes, the bacteria known to cause acne has been renamed as Cutibacterium acnes. Diets high in glycemic index (sugars, carbohydrates) and dairy products (milk, cheese, etc.) can worsen acneiform eruptions. The presence of acne-causing bacteria in combination with excess sebum, secreted from sebaceous glands in the skin, lead to pore clogging and development of acne lesions, which are classified in terms of lesion type and severity.

The various types of acne lesions include white heads (closed comedones), blackheads (open comedones), small bumps, and most severely inflamed and often painful cysts and nodules. Severity of acne is classified as mild (a few, occasional pimples), moderate (presence of inflammatory papules), and severe (presence of nodules and cysts). Acne is also classified as being inflammatory vs. non-inflammatory. The above photo illustrates the different types of acne and their classifications. Treatment of acne is based on these classifications - type of acne lesions present and the number of lesions present. It is important to note that much of the acne which brings patients to seek treatment is on the face, but acne can exist all over the body, including the chest and back.

A List of FDA-approved Drugs Used In the Treatment of Acne:

• Topical Products

  • Benzoyl Peroxide

  • Salicylic Acid

  • Azelaic Acid

  • Dapsone Gel

  • Topical Antibiotics

  • Topical Retinoids

• Oral Retinoids

  • Isotretinoin

    • *REMS program, birth defects

    • Females must have 2 negative pregnancy tests prior to initiation, must also be tested monthly and use 2 forms of birth control. Reserved for severe inflammatory acne.

• Oral Antibiotics

  • Minocycline/Doxycycline

  • Sarecycline

  • Erythromycin

  • SMX/TMP

Resources:

1) RxPrep 2021: Chapter 39: Common Skin Conditions. Acne. Pages 567-568.

There are a variety of drugs which can cause discoloration of the skin and secretions. Color change can be noticed in the skin, whites of the eyes, *****, saliva, sweat, feces etc. Drug-associated discoloration can vary across the rainbow from brown, green, purple, yellow, orange, red, and blue. As pharmacists, it is important for us to be familiar with the different drugs that can cause discoloration of the skin and secretions in order for us to properly counsel our patients. For example, a patient taking phenazopyridine should be warned that their ***** is likely to turn red/orange, because failure to warn the patient may result in fear and ultimately loss of trust between patient and provider. Below is a quick summary of common drugs in the United States which can alter the color of the skin and/or ****** fluids.

Many medications can turn skin or secretions brown, including entacapone, levodopa, and methyldopa. Iron can cause black stools, and methocarbamol can cause brown/black/green discoloration. Nitrofurantoin, Metronidazole, Tinidazole, and Riboflavin (B2) can cause yellow/brown discoloration. Chlorzoxazone is unique because it can cause purple, orange, and/or red secretions. Other medications known to cause red secretions are anthracylcines, deferasirox (***** only), phenazopyridine, rifampin, and rifapentine. Sulfasalazine is notorious for causing orange/yellow discolorations. Yellow/Green discolorations are common with propofol and flutamide. Medications which cause blue or blue/grey discoloration are methylene blue, mitoxantrone, amiodarone, and chloroquine.

Brown: entacapone, levodopa, methyldopa

Brown/Black/Green: iron (stool), methocarbamol

Brown/Yellow: nitrofurantoin, metronidazole, tinidazole, riboflavin (vitamin B2)

Purple/Orange/Red: chlorzoxazone Orange/Yellow: sulfasalazine

Yellow-Green: propofol, flutamide Red-Orange: phenazopyridine, rifampin, rifapentine Red: anthracyclines, deferasirox (*****)

Blue: methylene blue, mitoxantrone

Blue-Grey: amiodarone, chloroquine

Resources: 2021 RxPrep: Chapter 39: Common Skin Conditions. Pages 566-568.