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Comparative Efficacy of Topical N-Acetylcysteine-Doxycycline versus Benzoyl Peroxide-Doxycycline in Moderate Acne Vulgaris: An Add-on Double-Blind Randomized Controlled Trial

Mohammad Mahdi Parvizi, Parisa Mosallanezhad, Maryam Hekmat, Shohreh Alipour, Negin Fazelzadeh Haghighi
Dermatol Pract Concept 2026 16(2):6215

Bibliography

PubMed
PMID 42190184
PubMed Central
PMC13211913
DOI
10.5826/dpc.1602a6215
Funding
Supported by the Vice-chancellor of Research of Shiraz University of Medical Sciences (grant 28654).
Competing interests
The authors reported no competing interests.

Study snapshot

DesignDouble-blind randomized controlled add-on trial
ModelHuman
Sample40 patients with moderate acne vulgaris
InterventionOral doxycycline 100 mg/day plus topical 5% NAC versus doxycycline plus topical 5% benzoyl peroxide
Duration3 months
EndpointsTotal lesion count; Inflammatory lesions; Global Acne Grading System; Investigator Global Assessment; Acne quality of life

What the study showed, in plain terms

2026 randomized trial comparing topical 5% NAC with topical benzoyl peroxide, both used alongside doxycycline, in moderate acne.

Key findings

The NAC combination produced greater improvement across several acne severity and lesion-count measures with minimal reported adverse effects.

What this study can and cannot tell us

Only 40 participants, topical NAC rather than oral supplementation, and both groups received doxycycline; results do not establish oral NAC as a skin or acne supplement.

Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology