Dermatology High-Yield: Skin Conditions Every FNP Student Must Know

Clinical High-Yield · 9 min read · April 16, 2026

Acne Vulgaris

Pathophysiology: Sebum overproduction + follicular plugging + P. acnes colonization + inflammation

Classification:

  • Comedonal (non-inflammatory): Blackheads, whiteheads
  • Inflammatory: Papules, pustules
  • Nodular/cystic: Severe, scarring

Treatment (stepwise):

  • Mild comedonal: Topical retinoids (tretinoin, adapalene)
  • Mild-moderate inflammatory: Topical benzoyl peroxide ± topical antibiotics
  • Moderate: Add oral antibiotics (doxycycline, minocycline) — limit to 3 months
  • Severe/cystic: Isotretinoin (requires iPLEDGE program due to teratogenicity)
  • Women: Oral contraceptives or spironolactone as adjuncts

Atopic Dermatitis (Eczema)

Presentation: Pruritic, erythematous, scaly patches; flexural surfaces in adults; cheeks and extensor surfaces in infants

Treatment:

  • Moisturizers: Foundation of treatment — apply immediately after bathing
  • Topical corticosteroids: First-line for flares; use lowest potency effective
  • Topical calcineurin inhibitors (tacrolimus, pimecrolimus): Steroid-sparing, safe for face
  • Dupilumab: Biologic for moderate-severe disease
  • Antihistamines: For sleep disruption from pruritus

Psoriasis

Presentation: Well-demarcated, erythematous plaques with silvery scale; extensor surfaces (elbows, knees), scalp, nails (pitting, onycholysis)

Auspitz sign: Pinpoint bleeding when scale is removed

Treatment:

  • Mild-moderate: Topical corticosteroids, vitamin D analogues (calcipotriene), topical retinoids
  • Moderate-severe: Phototherapy (UVB), methotrexate, biologics (TNF inhibitors, IL-17 inhibitors)

Skin Infections

Impetigo: Honey-crusted lesions; S. aureus or Strep; topical mupirocin for localized, oral antibiotics for widespread

Cellulitis: Spreading erythema, warmth, tenderness; usually S. aureus or Strep; cephalexin or dicloxacillin; TMP-SMX if MRSA suspected

Tinea (ringworm): Annular, scaly plaques; topical antifungals (clotrimazole, terbinafine); oral terbinafine for tinea capitis and onychomycosis

Herpes zoster (shingles): Dermatomal vesicular rash; treat with valacyclovir within 72 hours of rash onset; postherpetic neuralgia treated with gabapentin, TCAs

Skin Cancer Recognition

Basal cell carcinoma (BCC): Most common; pearly papule with rolled borders, telangiectasias; rarely metastasizes

Squamous cell carcinoma (SCC): Scaly, ulcerated plaque; can metastasize; associated with actinic keratoses (precursor)

Melanoma (ABCDE rule):

  • Asymmetry
  • Border irregularity
  • Color variation
  • Diameter >6mm
  • Evolution (changing)

Board pearl: Any suspicious lesion should be referred for biopsy. Do not attempt to diagnose melanoma clinically — refer.