| Morbilliform Drug Rash | - Erythematous macules → confluent papules
- Trunk → extremities, symmetric
- Most common precipitants = antibiotics (beta-lactam antibiotics, sulfa drugs), allopurinol, AEDs, NSAIDs
- Sx: Pruritus, low grade fever
| - Discontinue offending agent
- Topical corticosteroids, wet wraps
- Sarna lotion for anti-itch effect
- Antihistamines
- If eosinophilia, kidney/liver dysfunction, mucous membrane lesions or painful/dusky lesions, consider alternative diagnoses (DRESS, AGEP, SJS/TEN)
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| Erythema Multiforme | - Abrupt onset of papular “targetoid” lesions in symmetrical acrofacial sites, +/-mucosal involvement (60-70% of cases)
- Usually precipitated by HSV
- Sx: Lesions can be painful, pruritic or swollen
- Systemic symptoms likely attributed to inciting infection (HSV, CMV, EBV, flu, COVID, etc)
- Additional triggers include drugs (antibiotics, anti-epileptics, NSAIDs, and vaccinations), and persistent cases can also be associated with inflammatory bowel disease, hepatitis C, and malignancies including leukemia, lymphoma, and solid organ cancers.
| - Oral antihistamines and/or topical steroids for itch
- Treat precipitating infections (HSV tx does not alter course of single episode, can help prevent future inf)
- Stop offending medications
- If recurrent, derm referral for prolonged antiviral course
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| Zoster | - Reactivation of VZV leading to blistering, painful rash in dermatomal distribution
- Rash can last 3-4 weeks
- Sx: Painful pustular lesions with systemic symptoms including fever, headache and lymphadenopathy
| - Best treatment is prevention (shingles vaccine in adults ≥50 or immunocompromised)
- Valacyclovir 1000 mg TID if symptoms started w/in 72 hours and patient has new lesions) for 7 days OR acyclovir 800 mg 5x daily for 7 days
- Can be complicated by post-herpetic neuralgia, manage w/ early antiviral treatment, topical capsaicin, TCAs, gabapentin/pregabalin
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| Seborrheic Dermatitis | - Inflammatory response to Malassezia yeasts
- Characterized by erythematous areas w/ yellowish and greasy scale of scalp, face, upper trunk, intertriginous areas
- Can be associated with HIV, Parkinson’s disease and use of neuroleptic medications; consider rescreening everyone for HIV
- Chronic, relapsing (mildest form = dandruff)
- Sx: usually itching, flaking, and erythema but sometimes non-itchy
| Scalp: - Mild disease (dandruff only): Antifungal shampoo - ketoconazole 2% (prescription) or selenium sulfide 2.5% (over the counter)
- Moderate to severe disease (with scaling, inflammation, and itching): Antifungal shampoo as first-line; if inadequate response, add a 2-week course of low potency topical corticosteroid such as fluocinolone acetonide 0.01% (can escalate to high potency fluocinonide 0.05% solution if refractory but avoid the face)
Face: - Mild to moderate disease: Ketoconazole 2% cream or other topical antifungal (e.g., ciclopirox) applied twice daily
- Moderate to severe disease or refractory cases: Short-term (up to 2 weeks) low-potency topical corticosteroid such as hydrocortisone 2.5% or desonide 0.05%, combined with antifungal therapy
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| Tinea | - Presentation depends on location
- Pedis: itchy scales with underlying erythema. Common types: Interdigital type: pruritic erosions and scaling between the toes. Moccasin type: hyperkeratotic scaling involving the soles and lateral aspects of the feet. Vesiculobullous type: vesicular and bullous lesions on the medial foot
- Corporis: solitary circular red patch with raised scaly leading edge, forms ring-shape with hypopigmentation
- Capitis: partial hair loss, +/-erythema, +/-pustular lesions
- Cruris: erythematous bilateral but asymmetrical rash with raised border and central clearing
- Onychomycosis: Perform KOH preparation if possible to confirm diagnosis
- Sx: Can be itchy and erythematous or asymptomatic
| - Treat all sources of tinea to prevent re-infection.
- Nystatin IS NOT effective treatment
- Pedis/Corporis/Cruris: if localized infection ok for topical antifungals (clotrimazole 1% BID until clinical resolution 1-4 weeks) or terbinafine 1% daily for 1-2 weeks
- Capitis: Oral griseofulvin (500-1000 mg daily for 4-6 weeks) or oral terbinafine (250 mg once daily for 4 to 6 weeks), terbinafine first line
- Onychomycosis: Oral terbinafine (250 mg once daily for 6 weeks (fingernail) or 12 weeks (toenail)), topical therapy (efinaconazole, amorolfine, ciclopirox)
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| Paronychia | - Inflammation of the skin around a finger or toenail
- Can be associated with felon (painful abscess at the base of the toe/nail) or herpetic whitlow (viral cutaneous infection caused by HSV)
- Usually due to staph/strep or pseudomonas
- Sx: Pain at the site of the infection, can develop systemic infection leading to fever/chills/myalgias
| - If no abscess formation, can manage with soaking affected digit in warm water and antiseptics (chlorhexidine soaks TID) with mupirocin applied after soaking
- If abscess present → I&D + culture
- Antibiotics indicated if symptoms not improving after I&D or systemic symptoms (dicloxacillin 500 mg QID, cephalexin 500 mg QID) for 5 day duration
- If risk factors for MRSA → Bactrim 1-2 DS tablets BID
- If oral flora present → augmentin 875/125 mg BID
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| HSV | - Present as clusters of 2-3 mm clear or hemorrhagic vesicles persisting for 5-10 days usually preceded by localized tingling/burning
- Type 1 most commonly associated with oral lesions, Type 2 w/ genital lesions
- Diagnose with viral culture of swab from vesicle or serologic testing (may be positive and not causing symptoms)
- Sx: Lesions are painful, can be associated with mild malaise and fever
| - No cure, following initial infection immunity develops but does not prevent against further attacks
- For initial infection: valacyclovir 1 g bid for 7-10d OR acyclovir 400 mg tid for 7-10 days
- For recurrent infections: valacyclovir 500 mg bid for 3 days OR 1 g once daily for 5 days OR acyclovir 800 mg twice daily for 5 days
- For suppressive therapy: valacyclovir 500 mg or 1 g daily OR acyclovir 400mg bid
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| Candida: | - Balanitis: inflammatory versus infectious condition of the glans penis. Most commonly infectious cause (candida versus dermatophytosis)
- Sx: penile soreness, dysuria, itchiness, bleeding and erythema of the glans
- Candidal balanitis associated with white, curd-like exudate
- Intertrigo: erythematous/macerated plaques with peripheral scaling, often associated with superficial satellite papules or pustules
- Affects skin below breasts or under abdomen, armpits, groin and web spaces between fingers/toes
| - Balanitis: attention to genital hygiene with retraction of foreskin and cleansing for prevention/therapy
- Clotrimazole cream BID for 7-14 days
- Intertrigo: Prevention with moisture-free skin, can use talcum powder to assist in intertriginous areas. Recommend drying well after showers/exercise/sweating and can recommend use of a blow dryer to the AA on a low/room temperature setting
- Topical clotrimazole, nystatin, or miconazole applied twice daily until resolution, typically 2-4 weeks.
- Oral fluconazole or itraconazole for severe, generalized and/or refractory cases
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Pityriasis versicolor
Pityriasis Rosacea | - Pityriasis (tinea) versicolor: Superficial fungal skin infection caused by Malassezia
- Hypo/hyperpigmented or erythematous macules/patches or thin plaques most common on upper trunk, upper extremities
- Sx: usually asymptomatic
- Pityriasis rosacea: Self-limiting rash (6-10 weeks) characterized by large circular/oval “herald patch” found on chest/abdomen or back followed by small scaly oval red patches on back and chest (sometimes described in Christmas tree pattern)
- Sx: vary from mild to severe itching. ⅔ of patients have flu-like symptoms prior to rash onset
| - Pityriasis versicolor: Topical antifungal treatment with ketoconazole 2% shampoo (daily for 3 days), selenium sulfide 2.25% shampoo or terbinafine 1% cream
- Pityriasis rosacea: Self-limiting disease therefore treatment is symptom management
- Apply daily moisturizing creams, avoid drying soaps
- Can trial medium potency topical steroids and oral antihistamines
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| Atopic Dermatitis (eczema) | - Lesions are pruritic, erythematous, +/- weeping/exudative, +/- blistering. Can become lichenified and scaly with fissuring over time.
- Most commonly occurs on neck, hands and flexural surfaces in adults
- Associated with atopic triad (asthma, eczema, and allergies)
| Eczema Management: Avoid triggers (fabrics, chemicals, humidity extremes, food allergens). Apply moisturizers daily; Ideally, unscented cream (Cerave, Vanicream) with emollient such as vaseline on top (Creams hydrate the skin and emollients prevent transepidermal water loss, but can do creams alone if patient is unable to tolerate emollients).
Face and Skin Folds: Low potency steroid twice daily x 2-3 weeks (no more than 20 days per month) or tacrolimus 0.1% twice daily until cleared.
Trunk and Extremities: Triamcinolone 0.1% for 2-3 weeks, no more than 20 days per month.
Refractory Cases: Refer to dermatology for systemic therapy |
| Psoriasis | - Well-defined pink-to-red and scaly plaques, often symmetrically distributed
- Most common locations are scalp, elbows, knees
- The main types of psoriasis are plaque (80% of cases), guttate (2%), pustular, erythrodermic (2-3%), and inverse, plus location-specific variants including palmoplantar, nail, genital, and sebopsoriasis.
- Sx: Pruritus is common but mostly mild, treating can lead to hyper/hypopigmented plaques that fade over time
| - Limited disease →topical corticosteroids and emollients
- Scalp/external ear canal: potent corticosteroids - clobetasol propionate 0.05% BID until lesions clear
- Face/intertriginous: low-potency OTC hydrocortisone 1% or prescription-strength 2.5% BID until lesions clear
- Thick plaques on extensor surfaces: clobetasol propionate 0.05% BID until lesions clear
- Moderate to Severe → Phototherapy + topical steroids/emollients, before systemic agents (e.g. MTX) or biologics targeting IL-17, IL-23, and TNF-α
- Avoid systemic steroids when possible (high risk for rebound flare that can be more severe than initial presentation)
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| Acne | - Open and closed comedones, noninflammatory versus inflamed papules/pustules
- Severe cases involve nodules, pseudocysts with scarring
| General Measures: - Sunscreen SPF ≥30 daily with broad spectrum coverage
Mild Acne (predominantly comedonal): - Topical retinoid (tretinoin, adapalene, or tazarotene) daily PLUS Benzoyl peroxide (if inflammatory/papulopustular lesions present)
- Alternative: Azelaic acid 15-20% cream twice daily (particularly helpful for sensitive skin or darker skin types due to lightening effect on postinflammatory hyperpigmentation)
Moderate Acne (inflammatory): - Topical retinoid daily PLUS Benzoyl peroxide daily PLUS
- Fixed-dose combination products (e.g., adapalene-benzoyl peroxide, clindamycin-benzoyl peroxide, tretinoin-clindamycin) OR oral doxycycline 100 mg daily or twice daily (or 40 mg modified-release daily) for 3-4 months maximum, then discontinue and maintain with topical therapy
- Important: Topical clindamycin should NOT be used as monotherapy due to antibiotic resistance concerns; always combine with benzoyl peroxide
Moderate-to-Severe Acne: - Oral doxycycline (100 mg daily or twice daily for 3-4 months) PLUS topical retinoid PLUS benzoyl peroxide OR Isotretinoin (cumulative dose 120-150 mg/kg) for severe, scarring, treatment-resistant, or psychosocially distressing acne.
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| Allergic Contact Dermatitis | - Type of eczema caused by allergic reaction to allergen (type IV hypersensitivity), usually 48-72 hours after exposure
- Symptoms include erythematous, indurated pruritic plaques, +/-edema, +/-blistering, +/-scale
- Consider triggers such as nickel, fragrances/perfumes, work exposures, poison ivy
| - Determine allergen, if not identified easily, can have comprehensive patch testing
- Acute/localized rash on hands/feet or nonflexural areas → mid- to high-potency topical steroids (such as triamcinolone 0.1% or clobetasol 0.05%) are effective until clearance
- Acute/localized rash on face/flexural areas → medium/low potency topical steroids BID for 1-2 weeks until resolution OR topical tacrolimus 0.1% until resolution
- Systemic corticosteroids are often required for extensive allergic contact dermatitis (involving >20% body surface area). Oral prednisone tapered over 2-3 weeks is recommended for severe cases, such as poison ivy dermatitis, to prevent rebound dermatitis
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| Stasis Dermatitis | - Caused by venous hypertension resulting from dysfunction of venous valves, obstruction to venous flow
- Sx: include edema, inflammatory skin changes, pruritus, tenderness, ulceration, varicosity and hyperpigmentation (hemosiderin deposition)
| - Compression therapy with bandaging systems or stockings, elevation of legs, regular exercise other than standing. Recommend ABIs before compression and recommend venous reflux study (not duplex)
- Emollient (petrolatum) application for dryness/pruritus
- Acute disease w/ erythema, pruritus, vesiculation, and oozing → consider mid-potency topical corticosteroids BID for 1-2 weeks
- Referral to vascular if persistent symptoms
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| Rosacea | - Chronic inflammatory condition affecting central face, usually appears between 30-60 yo
- Persistent facial redness, telangiectasia, thickening of skin and possible development of inflammatory papules/pustules. Can also see ocular rosacea (often presenting with dry eyes, eye irritation, foreign body sensation)
- Pathophysiology multifactorial, includes genetic susceptibility, immune dysregulation, neurocutaneous triggers (sunlight, temperature, exercise, spicy foods, alcohol, stress, and tobacco)
| - Learn/avoid triggers (alcohol, tobacco), use gentle skin care products, and sun protection
- Consider pharmacological intervention with topical brimonidine, laser or intense pulsed light therapy
- If complicated by papular/pustular disease, consider topical metronidazole 0.75% gel, topical ivermectin 1% cream, and azelaic acid 15% gel or foam for mild disease, and oral tetracycline/doxycycline for moderate to severe disease.
- For ocular rosacea, recommend oral doxycycline (100 mg BID) and referral to ophthalmology
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