I am a male with chronic localized groin bromhidrosis (primarily left inguinal fold) that persisted after treated tinea cruris and improves with short courses of topical clindamycin and benzoyl peroxide; what is the optimal long‑term management—do I need prolonged systemic antibiotics or extensive lifestyle modifications for durable control?

Optimal Long-Term Management of Groin Bromhidrosis After Clindamycin Response

You do not need prolonged systemic antibiotics or permanent lifestyle modification—your condition is a surface bacterial overgrowth that responds to short antibiotic courses and requires only intermittent maintenance with benzoyl peroxide and hygiene optimization, not lifelong behavioral restriction. 1

Understanding Your Clinical Pattern

Your presentation is classic apocrine bromhidrosis with secondary bacterial overgrowth (likely Corynebacterium species), not a deep biofilm infection requiring extended antibiotic therapy. 1 The key distinguishing features are:

• Surface-level pathology: Odor completely resolves with washing and returns only with occlusion/sweat, indicating bacterial metabolism of apocrine secretions rather than deep tissue infection 2, 1
• Trigger-dependent flares: Semen, urine, prolonged occlusion, and reduced activity all promote bacterial overgrowth through increased substrate and moisture 1
• Dramatic response to short clindamycin courses: This confirms susceptible bacterial overgrowth, not resistant biofilm requiring 6–12 months of therapy 3, 4

Why Extended Antibiotics Are Not Indicated

Biofilm infections requiring prolonged therapy (6–12 weeks to 12 months) involve foreign bodies, deep tissue invasion, or chronic wounds—none of which apply to your case. 5 The ESCMID biofilm guidelines reserve extended antibiotic courses for orthopedic implants, chronic osteomyelitis, and device-related infections with documented biofilm formation. 5 Your condition lacks:

• Persistent inflammation after adequate "source control" (washing removes the problem) 6
• Foreign material or deep tissue involvement 5
• Need for surgical debridement 6

Prolonged systemic antibiotics would create unnecessary antibiotic resistance risk without addressing the underlying apocrine gland physiology. 7

Evidence-Based Maintenance Strategy

Primary Maintenance: Benzoyl Peroxide

• Apply benzoyl peroxide 5% gel to affected areas 2–3 times weekly as maintenance between flares, not daily (which caused your irritation). 3, 4, 7
• Benzoyl peroxide prevents bacterial resistance (unlike clindamycin monotherapy) and provides sustained antibacterial effect through oxidative killing of surface bacteria. 3, 4
• The clindamycin/benzoyl peroxide combination gel used in hidradenitis suppurativa (another apocrine disorder) showed sustained benefit at 16 weeks with intermittent use. 7

Rescue Therapy: Short Clindamycin Courses

• Use topical clindamycin 1% solution for 5–7 days only when odor returns despite benzoyl peroxide maintenance. 5, 3
• The British Association of Dermatologists recommends clindamycin solution twice daily for apocrine-related conditions, with treatment breaks to limit resistance. 5
• Your pattern of 1-month suppression after 7-day courses is expected and appropriate—this is not "failure" requiring escalation. 3, 4

Hygiene Optimization (Not Lifestyle Restriction)

• Daily washing of inguinal folds with plain soap and thorough drying—this is your most effective intervention. 2, 1
• Absorbent powder (cornstarch-based) after showering on high-occlusion days. 1
• Rinse the area after ejaculation or urination rather than letting material sit in the fold. 1
• Trim (not necessarily shave) hair to reduce bacterial substrate and improve drying. 1

Addressing Your Specific Concerns

"Will sweat-related odor always be funky?"

Yes, some degree of apocrine odor with heavy sweating is physiologic—the goal is control, not elimination. 1 Normal apocrine secretion becomes malodorous only with bacterial overgrowth, which your current regimen prevents. 1 The fact that you had complete resolution during your active period with the dog (more activity, less occlusion, less masturbation) proves this is trigger-dependent, not a chronic infection requiring cure. 1

"Do I need 6–12 months of lifestyle change?"

No. The 6–12 month antibiotic durations in guidelines apply to orthopedic implant infections, chronic osteomyelitis, and prosthetic device biofilms—not surface skin conditions. 5 Your improvement with activity was due to:

• Reduced occlusion time (less bacterial growth substrate) 1
• Better hygiene from increased showering 2, 1
• Less semen/urine exposure in the fold 1

You need practical trigger management, not monastic lifestyle restriction. Showering after sweating, rinsing after ejaculation, and using powder on sedentary days is sufficient. 2, 1

"Will it just return when I stop being active?"

Partially, yes—but this is manageable with maintenance benzoyl peroxide, not a sign of treatment failure. 3, 4, 7 Your baseline severity is now dramatically reduced (you said it's "a non-issue"), and fluctuations with occlusion are expected. 1 The goal is keeping flares mild and infrequent, which you've achieved. 7

Practical Algorithm Going Forward

Baseline state (current):

• Benzoyl peroxide 5% gel to inguinal folds 2–3× weekly 3, 4
• Daily washing and drying 2, 1
• Powder on high-occlusion days 1

If odor returns (>30% of original severity for >1 week):

• Add topical clindamycin 1% solution twice daily for 5–7 days 5, 3
• Continue benzoyl peroxide during and after clindamycin 7
• Resume benzoyl peroxide-only maintenance after clindamycin course 7

If frequent relapses (requiring clindamycin >4 times/year):

• Consider clindamycin/benzoyl peroxide combination gel as maintenance (reduces resistance risk vs. clindamycin alone) 7
• Re-evaluate for erythrasma with Wood's lamp if plateau persists despite treatment 2

Common Pitfalls to Avoid

• Over-treating with daily benzoyl peroxide: This caused your irritation and paradoxical worsening. 3, 4 Intermittent use (2–3×/week) maintains antibacterial effect without irritation. 7
• Expecting zero odor with sweating: Physiologic apocrine odor exists; control means "rinse-off" odor, not complete absence. 1
• Pursuing systemic antibiotics: No evidence supports oral antibiotics for localized bromhidrosis, and resistance risk outweighs benefit. 5, 1
• Assuming lifestyle caused the problem: Occlusion and hygiene are triggers, not root causes—you don't need permanent behavioral change, just practical trigger management. 1