Female Groin Rash: Differential Diagnosis, Treatment, and Prevention

Groin rash (intertriginous dermatitis) in women has infectious, inflammatory, and irritant etiologies. Accurate diagnosis directs therapy.

Common Causes

Condition	Key Features	First-Line Treatment
Tinea cruris (jock itch)	Annular, scaly, advancing border; central clearing; pruritic; often bilateral thighs	Topical azole/terbinafine × 2–4 wks
Candidiasis (yeast)	Beefy red, satellite pustules, maceration; intense itch/burn; ± vaginal discharge	Topical nystatin/clotrimazole; oral fluconazole if extensive
Intertrigo (irritant)	Symmetric erythema, maceration, fissuring in folds; moisture/friction driven	Dryness, barrier (zinc oxide, petrolatum), weight loss, loose clothing
Contact dermatitis	Erythema, vesicles, edema; sharp demarcation at contact site; allergen (nickel, latex, fragrance, detergent)	Identify/avoid trigger; topical steroid (low-potency) short course
Psoriasis (inverse)	Well-demarcated, shiny, non-scaly red plaques in folds; ± nail pitting, scalp plaques	Low-potency steroid, calcineurin inhibitor (tacrolimus), vitamin D analog
Hidradenitis suppurativa	Recurrent painful nodules, abscesses, sinus tracts, scarring in axillae/groin	Antiseptic washes, topical clindamycin, oral antibiotics, biologics (adalimumab)
Erythrasma	Brown, finely scaling patches; coral-red fluorescence (Wood's lamp); Corynebacterium	Topical/oral erythromycin or clindamycin
Pubic lice (phthiriasis)	Intense itch; nits on hair shafts; excoriations	Permethrin 1% or pyrethrins; treat contacts

Diagnostic Pearls

• KOH prep: hyphae (dermatophyte), pseudohyphae/budding yeast (candida).
• Wood's lamp: coral-red (erythrasma), green (pseudomonas).
• Biopsy if atypical, refractory, or suspicion of malignancy (extramammary Paget's).

Prevention & Maintenance

• Keep area clean, dry, cool. Pat dry; hair dryer cool setting.
• Cotton underwear; avoid tight synthetics, thongs.
• Weight loss if obese (reduces fold depth).
• Manage diabetes (glycemic control ↓ candidiasis).
• Barrier creams (dimethicone, zinc) for incontinence.

Persistent or recurrent rash → dermatology or gynecology referral. Avoid self-treating with high-potency steroids on thin genital skin.