Acne Vulgaris Treatment
Foundation: Start All Patients on Topical Retinoid + Benzoyl Peroxide
Begin treatment with adapalene 0.1-0.3% combined with benzoyl peroxide 2.5-5% applied once daily in the evening as the foundation for all acne therapy, regardless of severity. 1, 2
This combination addresses multiple pathogenic factors: adapalene targets abnormal follicular keratinization and microcomedones while benzoyl peroxide provides antimicrobial activity without risk of bacterial resistance. 1, 3
Why Adapalene Over Other Retinoids?
- Adapalene is superior in tolerability compared to tretinoin while maintaining equivalent or better efficacy, with 46% reduction in noninflammatory lesions versus 33% for tretinoin at 12 weeks. 1, 4
- No photolability concerns - can be applied with benzoyl peroxide without oxidation, unlike traditional tretinoin formulations. 1
- Available over-the-counter at 0.1% concentration, improving accessibility. 1, 5
Application Instructions
- Apply once daily in the evening after washing face and waiting 20-30 minutes for skin to completely dry. 1, 6
- Use pea-sized amount for entire face (forehead, chin, each cheek). 1
- Avoid corners of nose, mouth, eyes, and open wounds. 6
- Expect initial irritation or apparent worsening in first 2-4 weeks as medication acts on deep lesions - this is normal and not a reason to discontinue. 1, 6
Severity-Based Treatment Algorithm
Mild Acne (Predominantly Comedonal)
Continue with topical retinoid + benzoyl peroxide alone. 1, 2
- This combination is sufficient for mild disease without need for additional agents. 1
- Consider azelaic acid as alternative if post-inflammatory hyperpigmentation is present, particularly in darker skin tones. 1
Moderate Acne (Mixed Comedonal and Inflammatory)
Add fixed-dose combination topical antibiotic (clindamycin 1% or erythromycin 3%) with benzoyl peroxide to the retinoid + benzoyl peroxide regimen. 1, 2
- Fixed-combination products (clindamycin 1%/BP 5%, clindamycin 1%/BP 3.75%, erythromycin 3%/BP 5%) enhance compliance and prevent antibiotic resistance. 1, 3
- Never use topical antibiotics as monotherapy - resistance develops rapidly without concurrent benzoyl peroxide. 1, 2, 7
- Topical dapsone 5% gel is particularly effective for inflammatory acne in adult females and requires no G6PD testing. 1
Moderate-to-Severe Inflammatory Acne
Initiate triple therapy: oral antibiotic + topical retinoid + benzoyl peroxide. 1, 2
Oral Antibiotic Selection:
- Doxycycline 100 mg once daily (strongly recommended with moderate evidence). 1, 2
- Minocycline 100 mg once daily as alternative (conditionally recommended). 1
- Sarecycline is a newer tetracycline option. 1
Critical Antibiotic Limitations:
- Limit systemic antibiotics to maximum 3-4 months to prevent resistance. 1, 2, 7
- Always combine with benzoyl peroxide to prevent bacterial resistance. 1, 2
- Transition to topical retinoid monotherapy for maintenance after clearing. 1, 2
Severe Acne or Special Indications for Isotretinoin
Isotretinoin is the definitive treatment and should be initiated immediately for:
- Severe nodular or conglobate acne 1
- Any acne with scarring (presence of scarring alone classifies as severe) 1, 8
- Moderate acne with significant psychosocial burden 1
- Treatment-resistant moderate acne after 3-4 months of appropriate therapy 1
Isotretinoin Dosing and Monitoring
- Standard dosing: 0.5-1.0 mg/kg/day targeting cumulative dose of 120-150 mg/kg. 1
- Daily dosing preferred over intermittent dosing. 1
- Monitor only liver function tests and lipids - CBC monitoring not needed in healthy patients. 1
- No routine monitoring for depression or inflammatory bowel disease - population studies have not identified increased risk. 1
Mandatory Pregnancy Prevention
- All persons of childbearing potential must enroll in iPledge program before starting isotretinoin. 1, 6, 7
- Isotretinoin is highly teratogenic (Category D/X). 1
Adjunctive Therapy for Severe Acne
- Intralesional triamcinolone acetonide 10 mg/mL for individual large, painful nodules provides rapid pain relief within 48-72 hours. 1, 8
- Short-term oral corticosteroids can provide temporary benefit while initiating standard therapy. 1
Hormonal Therapy for Female Patients
Consider combined oral contraceptives or spironolactone for females with:
- Hormonal acne patterns (jawline/lower face distribution) 1
- Premenstrual flares 1
- Inability to tolerate or preference to avoid oral antibiotics 1
Combined Oral Contraceptives
- Reduce inflammatory lesions by 62% at 6 months. 1, 2
- Can be used as monotherapy or combined with topical agents. 1
Spironolactone
- Dosing: 25-200 mg daily. 1, 2
- No potassium monitoring needed in healthy patients without risk factors for hyperkalemia. 1
Maintenance Therapy After Clearing
Continue topical retinoid monotherapy indefinitely to prevent recurrence. 1, 2
- Benzoyl peroxide can also be continued for maintenance. 1, 2
- This is essential as acne is a chronic disease with high recurrence rates without maintenance. 1
Special Populations
Preadolescent Children (≥9 years)
- Topical adapalene, tretinoin, and benzoyl peroxide are safe. 1
- Start with benzoyl peroxide 2.5% for children under 12. 2
- Tetracycline antibiotics contraindicated in children <8 years due to permanent tooth discoloration risk. 1, 2
Pregnant Patients
- Azelaic acid is safer alternative (pregnancy category B) compared to retinoids (category C) or tazarotene (category X). 1
- Tretinoin safety in pregnancy not established - avoid if pregnant or nursing. 6
Critical Pitfalls to Avoid
Never use topical or oral antibiotics as monotherapy - resistance develops rapidly without concurrent benzoyl peroxide. 1, 2, 7, 3
Never extend oral antibiotics beyond 3-4 months without re-evaluation - dramatically increases resistance risk. 1, 2
Do not underestimate severity when scarring is present - scarring alone warrants consideration of isotretinoin regardless of active lesion count. 1, 8
Do not apply tretinoin with benzoyl peroxide simultaneously - oxidation inactivates tretinoin (adapalene does not have this limitation). 1
Do not use oral antibiotics as primary therapy for severe/conglobate acne - they are inadequate and delay definitive isotretinoin treatment. 1
Always assess psychological impact - severe psychosocial burden warrants more aggressive treatment regardless of objective severity. 1, 2
Additional Considerations
Complementary Topical Options
- Clascoterone (topical antiandrogen) - conditionally recommended based on high certainty evidence. 1
- Salicylic acid 0.5-2% - over-the-counter comedolytic with limited clinical trial evidence; 20-30% chemical peels for resistant comedonal acne. 1
- Azelaic acid - particularly useful for post-inflammatory hyperpigmentation in darker skin tones. 1
Photosensitivity Precautions
- Daily sunscreen use mandatory with retinoids due to photosensitivity risk. 1
- Tetracycline antibiotics also cause photosensitivity. 1