Dermatologic Disorders

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CHAPTER 11 Dermatologic Disorders

I. Acne

Acne is an inflammatory disease of the sebaceous glands (oil-producing glands) and hair follicles of the skin. Acne is marked by the eruption of pimples or pustules, especially on the face, back, and chest. Typically, acne treatments take four to eight weeks for full results.

A. Conventional acne treatments are based on the concepts of:

1. Reducing sebum production
2. Speeding up skin cell turnover
3. Fighting bacterial infection (i.e., Propionibacterium acnes)

B. Over-the-counter (OTC) topical treatments may dry up the oil, reduce bacteria, and promote exfoliation.

1. Benzoyl peroxide (e.g., Clean and Clear, Persa-Gel, Oxy 10 Spot Treatment)

a) Also available in prescription preparations alone or in combination with sulfur or a topical antibiotic

2. Salicylic acid (e.g., Biore Blemish Bomb, Clearasil Stay Clear, Zone Control Clearstic).
3. Sulfur and/or resorcinol (e.g., Clearasil Adult Care)
NOTE: Common side effects for all topical retinoids include skin dryness, peeling, redness, photo sensitivity

C. Prescription topical retinoid products that are derived from vitamin A work by promoting cell turnover and preventing blockage of the hair follicle.

1. Tretinoin (Avita, Retin-A, Renova)
2. Adapalene (Differin)
3. Tazarotene (Tazorac)

D. Antibiotics

For moderate to severe acne (inflammatory or nodulocystic acne), prescription oral or topical antibiotics may be needed to reduce bacteria and fight inflammation. Antibiotics may be used for months or years to control acne and may be used alone or in combination with topical therapy. Antibiotics can also lessen the effectiveness of birth control pills by killing beneficial bacteria in the gastrointestinal tract that are responsible for hormone metabolism.

1. Erythromycin (Erygel, Emcin, Emgel, Akne-mycin, others)

a) Anti-inflammatory properties that help reduce redness in lesions, in addition to killing bacteria
b) Dose

(1) Varies with the type used
(2) Topical application (gel, solution, medicated pledget): Applied twice daily to affected area(s).
(3) If given systemically, initial dose 500 mg PO twice a day and taken with food; dosage reduced to 250–500 mg/day PO after several weeks once improvement is seen.

c) Side effects

(1) Stomach upset and nausea, but can be used in pregnant women

2. Clindamycin (Cleocin T, Clindagel, Clindaderm, Evoclin, others)

a) Widely prescribed as a topical antibiotic for acne, rarely used systemically for acne due to side-effect profile
b) Topical dose

1) Gel, solutions, or lotion: Applied twice daily to affected area(s)
2) Foam: Applied once daily to affected area(s)

c) Side effects

(1) Serious intestinal infection, pseudomembranous colitis, caused by the bacteria Clostridium difficile. This side effect has been reported rarely with topical clindamycin use.

3. Tetracycline

a) Most widely prescribed oral antibiotic for acne
b) Dose

(1) Initially, 500 mg PO twice a day until a significant decrease in acne lesions is seen; dose may then be decreased to 250–500 mg PO once a day.
(2) Tetracycline antibiotics must be taken on an empty stomach to be most effective.

c) Caution

(1) Not recommended for pregnant women or children younger than 9 years because tooth discoloration of the forming teeth is common in children. If all permanent teeth have erupted, tetracycline antibiotics may be a choice in select preteens.
(2) All tetracyclines may cause sun sensitivity.

d) Other tetracyclines used for acne include minocycline (Minocin, initially 50–100 mg PO twice daily, especially useful for pustular type acne) and doxycycline (Vibramycin, initially 50–100 mg PO twice daily).

4. Isotretinoin (Accutane, Claravis, Sotret)

a) Effective for scarring cystic acne or acne that does not respond to other treatments. It is reserved for the most severe forms of acne.
b) Side effects

(1) Severe mental disorders including depression and suicide
(2) Heart, brain, bone/muscle, gastrointestinal, cholesterol, hearing, vision, and liver problems
(3) Severe allergic reactions
(4) Teratogenic

c) Caution

(1) Close monitoring is essential to possibility of severe birth defects
(2) Contraindicated in women trying to become pregnant or during pregnancy
(3) Pharmacists must also provide a detailed warning brochure called a MedGuide from the United States Food and Drug Administration (FDA) to all patients prescribed isotretinoin. All prescribers, pharmacies, and patients must also register and participate in the iPledge risk-management program in order to prescribe, dispsense, or receive the drug.

E. Oral contraceptives (OC)

1. May exacerbate or improve acne depending on the progesterone component’s androgenic activity. Those with greater androgenic activity (levonorgestrel) tend to exacerbate acne, and those with less (norgestimate) or no (drospirenone) androgenic activity have been reported to improve acne in women.
2. Oral contraceptives increase the risk of thromboembolic events, especially in women older than 35 years who smoke. Remember ACHES acronym to remember thromboembolic warning signs: Abdominal pain, Chest pain, Headache or pain or changes in the eyes, severe pain or swelling in the legs or the thighs
3. Adverse effects include breast enlargement and tenderness, GI upset, irregular vaginal bleeding, especially during the first 3 months of therapy.
4. Examples of OC brands that are FDA approved for the treatment of acne (acne dosage is the same as for the OC regimen):

a) Ethinyl estradiol; Drospirenone (Yaz)
b) Ethinyl estradiol; Norethindrone acetate (Estrostep)
c) Ethinyl estradiol; Norgestimate (Ortho Tri-Cyclen)

II. Alopecia

A. Alopecia areata: an autoimmune disorder in which the body’s immune system attacks hair follicles, resulting in unpredictable patches of hair loss on the scalp, face, and other parts of the body.

1. Treatment

a) Corticosteroids: betamethasone (Celestone), monthly injections into the scalp
b) Corticosteroid pills
c) Corticosteroid creams and ointments, such as betamethasone (Diprolene), have been applied to affected areas of the skin. However, creams and ointments are generally less effective than injections.

B. Androgenic alopecia: an inherited form of baldness. Unlike men, women rarely develop complete baldness. Women usually experience hair thinning only.

1. Treatment

a) Minoxidil (Rogaine)

(1) Available OTC. Applied directly to the area of hair loss at least two times a day for at least 4 months. The medication usually does not take effect until 4 months to 1 year.
(2) Mechanism of action

(a) Enlarges hair follicles

(3) Caution

(a) Patients who discontinue use of minoxidil will likely lose the hair that they have already grown.

b) Finasteride (Propecia)

(1) Only works in men. This pill must be taken daily to regrow hair.
(2) Dose

(a) 1 mg PO once daily

(3) Mechanism of action

(a) Inhibits high levels of dihydrotestosterone (DHT) around hair follicles. High amounts of DHT cause hair follicles to shrink, and hair falls out as a result.

(4) Caution

(a) Pregnant women and women hoping to become pregnant should avoid contact (including topical contact) with finasteride due to the risk of genital abnormalities to a male fetus.

c) Spironolactone (Aldactone)

(1) Originally marketed as a diuretic (water pill) for patients suffering from congestive heart failure. Women now take the drug off-label because its antiandrogen properties may stop and sometimes reverse hair loss. It may also be more effective in postmenopausal women and may be taken with a hormone replacement pill.
(2) It is taken initially at a low dosage (25 mg) once or twice daily. Incremental dosage increases may be used, if needed.
(3) This medication may take many months to show results in women.

d) Cimetidine (Tagamet)

(1) Initially used as a prescription drug to treat heartburn and stomach ulcers. Recently, this medication became available OTC.
(2) Although primarily used as a histamine-blocking agent, it is also has some antiandrogen effects and thus only works for women. Cimetidine has been used off-label to treat androgenic alopecia in women.

III. Dry Skin (Xerosis)

A. Treatment with emollients and/or keratolytic agents; usual application is twice per day, unless otherwise noted on label or directed by prescriber.

1. Lactic acid, glycolic acid, salicylic acid, urea, and sulfur
2. Ammonium lactate (Lac-Hydrin, others)
3. Petrolatum (Aquaphor)

IV. Dermatitis

A. Atopic dermatitis (eczema) is a chronic disease, and symptoms can disappear and recur over time. The skin of an affected individual is flaky, red, and itchy. The skin covering the joints and face is most commonly affected. Symptoms can be managed. Minimizing contact with known allergens can reduce the severity of symptoms.

1. Treatment

a) Avoidance of any exacerbating allergens, contact irritants, foods, or environmental factors
b) Antianxiety medications: The condition can cause stress and anxiety; nonpharmacologic methods to reduce stress factors are typically employed before medication
c) Antibiotics: If co-infection exists
d) Antihistamines like diphenhydramine (e.g., Benadryl) and hydroxyzine (e.g., Atarax)
e) Calcineurin inhibitors like pimecrolimus (Elidel) and tacrolimus (Protopic)
f) Immunosuppressants such as cyclosporine or interferon
g) Oral corticosteroids such as prednisone and prednisolone
h) Topical corticosteroids such as hydrocortisone, betamethasone, or fluticasone propionate or OTC hydrocortisone (e.g., Bactine, Cortaid, Dermolate, or Aveeno Anti-Itch cream). Higher-strength (>1%) topical corticosteroids are available by prescriptions only.

B. Contact dermatitis: a rash that develops after contact with an allergen or skin irritant. Poison ivy, poison oak, and poison sumac produce urushiol, an oil and the allergen responsible for the allergic reaction that usually develops 24–48 hours after contact with the oil. However, it can take several days to 1–2 weeks for the rash to resolve. Patients who are allergic to these plants may experience a rash that consists of swollen, itchy, red bumps and blisters that appear wherever the oil has touched the skin.

1) Prevention: Avoidance of contact irritants, wearing of protectant clothing and gloves if irritant exposure is possible or cannot be avoided, skin protectant lotions like Ivy-Block can be tried, but must be applied at least 15 minutes before exposure and reapplied often (after 4 hours) if activity is prolonged.
2) Treatment and relief from symptoms

(a) General care includes removal of contaminated clothing and washing the affected skin with soap and cool water. Washing within 10 minutes of exposure may help limit the reaction.
(b) Systemic antihistamine such as diphenhydramine (Benadryl). Topical application of diphenhydramine is not recommended because it can cause sensitization.
(c) Calamine lotion (e.g., Calamox) applied three to four times per day; allow to dry before putting on clothing
(d) Cool showers or compresses
(e) Colloidal oatmeal such as Aveeno Oatmeal Bath
(f) Topical corticosteroids (e.g., hydrocortisone cream)
(g) Oral corticosteroids (e.g., prednisone used for refractory cases or cases with complications)
(h) Consumers often tout the usefulness of home remedies for relief from itching, including baking soda, vinegar, and aloe vera

V. Pediculosis and Scabies

Lice and scabies are two types of skin conditions that are caused by ectoparasites, parasites that that live on the outside of their hosts.

A. Treatment

1. General

a) Treated with OTC products and/or prescription-strength antiparasitic medications.
b) To prevent reinfection, it is recommended that individuals wash and vacuum items that may be contaminated.
c) Individuals who live with or have close personal contact with someone who has lice or scabies should receive treatment as well.

2. OTC

a) Pyrethrins and piperonyl butoxide (e.g., Pronto) do not kill nits, need to re-treat in 7–10 days
b) Permethrin (e.g., Nix, RID) kills lice and eggs, may require only one application

3. Prescription

a) Malathion (Ovide)
b) Lindane (Kwell) Caution: Neurotoxic. Inappropriate application, inappropriate contact, or too-frequent or excessive application may cause seizures and other serious reactions.

4. Scabicides, such as Lindane, permethrin (Acticin or Elimite), or crotamiton (Eurax Cream or Eurax Lotion)
5. Antihistamines

VI. Warts

A. Common warts, flat warts, plantar warts (caused by human papillomaviruses [HPV])

1. Treatment

a) Salicylic acid 17% (Compound W, Occlusal-HP)
b) Patient-administered cryotherapy OTC products (e.g., Compound W Freeze-Off)
c) Provider-administered cryotherapy

B. Anogenital warts (caused by select types of HPV)

1. Treatment

a) Administered by physician

(1) Cryotherapy with liquid nitrogen, cryoprobe weekly, or surgical removal
(2) Podophyllin resin, 10%–25% weekly for a maximum of 4 weeks
(3) Trichloroacetic acid or bichloroacetic acid, 80%–90% weekly

b) Administered by patient, but available by prescription only after proper diagnosis

(1) Podofilox (Condylox), 0.5% solution or gel twice daily for 3 days, followed by 4 days without therapy. This cycle may be repeated four times.
(2) Imiquimod (Aldara), 5% cream three times per week for a maximum of 16 weeks

VII. Psoriasis

Psoriasis is a chronic skin disease characterized by scaly, reddish patches and itching. The inflammation sometimes manifests as silvery scales that appear on elbows, knees, scalp, and torso. It is not contagious. The cause is generally unknown, although recent studies suggest that it is an autoimmune disorder.

A. Topical treatments for localized exacerbations

1. Corticosteroids
2. Calcipotriene (Dovonex): applied to affected area once or twice daily
3. Tazarotene (Tazorac): applied once daily to affected area
4. Coal tar

B. Systemic treatments

1. Oral

a) Methotrexate

(1) Antimetabolite
(2) Dosed weekly
(3) Adverse effects: hepatotoxicity, pulmonary toxicity, pancytopenia, potential for increased malignancies, ulcerative stomatitis, nausea, diarrhea, teratogenicity

b) Acitretin (Soriatane)

(1) Retinoid
(2) Adverse effects: teratogenicity, osteophyte formation, hyperlipidemia, flare of inflammatory bowel disease, hepatoxicity, depression

c) Cyclosporine (Neoral, Sandimmune)

(1) Calcineurin inhibitor
(2) Adverse effects: renal dysfunction, hypertension, hyperkalemia, hyperuricemia, hypomagnesemia, hyperlipidemia, increased risk of malignancies

d) Methoxsalen

(1) Psoralen photosensitizing agent
(2) Used in conjunction with UVA light exposure therapy

2. Parenteral

a) Alefacept (Amevive)

(1) Anti-CD-2
(2) IM injection once weekly for 12 weeks
(3) Adverse effects: Lymphopenia, potential for increased malignancies, serious infections

b) Etanercept (Enbrel)

(1) Anti-Tumor Necrosis Factor Alpha (TNF-α)
(2) Approved for psoriasis and psoriatic arthritis
(3) SC injection once or twice weekly
(4) Adverse effects: serious infections, neurologic events, hematologic events, potential for increased malignancies

c) Efalizumab (Raptiva)

(1) Anti-CD-11a
(2) SC injection once weekly
(3) Adverse effects: serious infections, potential for increased malignancies, thrombocytopenia, hemolytic anemia, worsening psoriasis

d) Adalimumab (Humira)

(1) Anti-TNF-α
(2) Approved for psoriatic arthritis
(3) SC injection every other week
(4) Adverse effects: serious infections, neurologic events, potential for increased malignancies, hypersensitivity reactions, hematologic events

e) Infliximab (Remicade)

(1) Anti-TNF-α
(2) Approved for psoriatic arthritis
(3) IV infusion at weeks 1, 2, and 6, then every 8 weeks
(4) Adverse effects: serious infections, hepatotoxicity, hematologic events, hypersensitivity reactions, neurologic events, potential for increased malignancies

VIII. Common Dermatologic Fungal Infections

A. Tinea corporis (ringworm)
B. Tinea cruris (jock itch)
C. Tinea pedis (athletes’ foot)

1. Topical treatment with azole antifungals; many agents available without prescription (OTC)
2. Longer duration of therapy required for tinea pedis versus other tinea infections

D. Onychomycosis (toenails or fingernails)

1. Mild infections may be treated with topical antifungal lacquers (e.g., ciclopirox,)
2. Oral antifungal medication (e.g., itraconazole, terbinafine) may be required for several months

IX. Dermatologic Bacterial Infections

A. Impetigo (S. aureus or S. pyogenes): Highly contagious skin condition, with small oozing, crusting blisters, it usually begins on hands or face and rapidly spreads.

1. Treatment

a) Topical antibiotics (mupiricin [Bactroban] 2%, retapamulin [Altabax])
b) Oral antibiotics (e.g., amoxicillin/clavulanate [Augmentin], cefadroxil [Duricef], levofloxacin [Levaquin])

PATIENT PROFILE

Patient Initials: TH
Sex: Male
Age: 43 years
Height: 5′ 11″
Weight: 82 kg
Race: White
Allergies: Penicillin
Chief Complaint:
RM is a 43-year-old man seeking pharmacist assistance for the ongoing topical maintenance management of his psoriasis. His condition is classified as moderate to severe and has affected his joints (symptoms and signs in his hands and knees are consistent with psoriatic arthritis). He has scaling and plaques on more than 20% of his skin.
Recent History: TH underwent biologic aortic valve replacement (BAVR) last month due to newly found congenital valvular disease. He is doing well after open heart surgery to replace the valve.
Social History:
Tobacco use: None
Alcohol use: 1 beer per week, socially
Work: Unemployed; receives disability compensation due to affect of psoriasis on the joints in hands (was formerly a chef)
Exercise: Walks 2 miles daily for heart health and to maintain joint mobility
Medications:
Prednisone 20 mg PO once daily
Tylenol with codeine #3 q6h prn pain (uses roughly once or twice daily)
Metoprolol 25 mg PO twice daily
Warfarin 5 mg PO once daily
Multivitamin with minerals PO once daily
Past medication notes: No longer taking Naprosyn 500 mg PO twice daily after open heart surgery due to warfarin prescription, which is expected to continue for another 2 months; had to discontinue infliximab (Remicade) infusion treatments last year due to cardiac symptoms (slight symptoms of mild heart failure).

PATIENT PROFILE QUESTIONS

1. TH asks the pharmacist about skin hygiene tactics that may be useful in limiting scaling and improving skin appearance and that would not interact with his current prescribed medications. Which of the following topical skin care adjuncts are typically recommended for patients with psoriasis?

I. Emollients
II. Keratolytics
III. Topical nonprescription corticosteroids
a. I only
b. II only
c. III only
d. I and II
e. I and III

Answer: d. Given the extensive nature of TH’s disease (greater than 20% of body) and information from the course of his treatment history and current medications, topical nonprescription corticosteroids would not be recommended. Nonprescription corticosteroid products would not be of sufficient potency to be helpful. Topical corticosteroids and calcipotriene topically are typically used as first-line therapy in patients with limited psoriatic plaques. TH does not have limited disease and already receives systemic corticosteroid treatment. Current guidelines recommend that all patients with psoriasis maintain good skin hygiene. Nearly all patients with psoriasis generally find emollients and keratolytic agents helpful in improving skin appearance and reducing skin itching.

2. Which of the following is an example of a keratolytic agent that TH might employ?

a. AmLactin
b. Eucerin Creme
c. PsoriGel

Answer: a. AmLactin contains lactic acid, a keratinolytic agent. Keratinolytics break down keratin, a fibrous protein in skin cells, and this process helps remove the dead, keratinized cells of the stratum corneum (outer skin layer). Skin may look smoother after the use of these agents, which may help plaque appearance. The original formula of Eucerin creme contains emollients to increase skin hydration. PsoriGel (coal tar) may decrease skin proliferation and have anti-inflammatory properties; however, a precise mechanism in psoriasis is not clear.

REVIEW QUESTIONS

(Answers and Rationales on page 356.)

1. The hospital pharmacy in which you work has added mometasone 0.1% cream as the preferred medium potency topical steroid. Which of the following is a medium potency topical steroid and is being replaced by mometasone?

a. Desonide 0.05% cream
b. Mometasone 1% cream
c. Triamcinolone 0.1% cream
d. Clobetasol 0.05% cream
e. Clobetasol 10.0% cream

2. Dexamethasone may be used in the treatment of all of the following EXCEPT:

a. Addison’s disease
b. dermatitis
c. asthma
d. osteoporosis

3. Which of the following is first-line therapy for mild rosacea?

a. Topical metronidazole
b. Adapalene gel
c. Oral doxycycline
d. Oral metronidazole for 7 days
e. a and c

Read the following case study and then answer the questions that follow.

A 25-year-old woman with no medical history presents to a clinic with a rash that has lasted 3 months. The rash is limited to the posterior elbows and knees and is not pruritic. On examination, the rash is scaly and white with an erythematous edge. It is sharply demarcated and raised from the surrounding normal skin. She reports a similar rash in her mother that lasted several years.

4. Which of the following increases the risk of psoriasis?

a. Smoking
b. Old age
c. Low body weight
d. Over-cleansing of skin
e. Exposure to animals

5. What is an appropriate treatment for mild psoriasis?

a. Topical hydrocortisone
b. Oral prednisone
c. Methotrexate
d. Avoidance of sunlight
e. Any of the above

6. How does methotrexate alleviate psoriasis?

a. Prevention of fungal growth
b. Stimulation of epidermal regeneration
c. T-cell suppression
d. Mast cell stimulation
e. Antiangiogenic effects

7. Which of the following is a high potency steroid in appropriate strength for second-line psoriasis treatment?

a. Clobetasol 5%
b. Clobetasol 0.05%
c. Betamethasone 0.01%
d. Betamethasone 1%
e. Halcinonide 10%

8. Side effects of topical corticosteroids include:

a. pruritus
b. erythema
c. folliculitis
d. hypertrichosis
e. All of the above

9. Which of the following is NOT an indication for methotrexate?

a. Lymphoma
b. Rheumatoid arthritis
c. Esophageal cancer
d. Choriocarcinoma
e. All of the above are indications for methotrexate

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