How the 2024 Acne Guidelines Grade Treatments and Fight Antibiotic Resistance

The 2024 American Academy of Dermatology (AAD) acne guidelines grade every treatment on two separate axes rather than one: how strongly the therapy is recommended, and how certain the underlying evidence is. Published in the Journal of the American Academy of Dermatology by Reynolds and colleagues in 2024, the update applies the GRADE framework to produce 18 evidence-based recommendations and 5 good practice statements. Benzoyl peroxide, topical retinoids, topical antibiotics, oral doxycycline, and their fixed-dose combinations all receive strong recommendations at moderate certainty. Topical antibiotic used by itself, by contrast, is explicitly not recommended, and much of the document reads as a sustained case for antibiotic stewardship.

Two questions the grading keeps apart

A frequent misreading treats "strong recommendation" and "high-quality evidence" as the same stamp. GRADE separates them deliberately. Recommendation strength reflects the full balance of benefits, harms, patient values, cost, and practicality. Certainty of evidence reflects only how much confidence the trial data themselves warrant. Those two judgments can point in different directions, and in acne care they often do.

The guideline shows the split cleanly. Benzoyl peroxide and topical retinoids carry strong recommendations, yet the certainty behind them is graded moderate rather than high. Two newer agents run the opposite way. The topical androgen-receptor inhibitor clascoterone and the narrow-spectrum oral tetracycline sarecycline are each backed by high-certainty evidence yet receive only conditional recommendations. The trials behind these newer drugs were well designed, so the data quality is strong; the guideline attributes the more tentative endorsement to their high current cost, which the authors note may affect equitable access to treatment. Decades of consistent benefit kept the older topicals in the strong tier even though their evidence base is graded a notch lower. Reading the letter grade alone would invert the real message.

Why benzoyl peroxide and retinoids anchor the strong tier

Benzoyl peroxide sits at the center of the guideline for two reasons that reinforce each other. It works across the main drivers of acne, and it does something antibiotics cannot: it reduces bacteria without selecting for resistant strains. The guideline pairs its strong recommendation for topical antibiotics with a companion recommendation for benzoyl peroxide precisely because the combination blunts the emergence of resistant Cutibacterium acnes.

Topical retinoids earn their strong recommendation on a different mechanism. They normalize how skin cells shed and mature, addressing the clogged follicle that precedes visible lesions, and they add an anti-inflammatory effect. Because retinoids and benzoyl peroxide attack separate steps, the guideline treats them as complementary rather than interchangeable. That logic carries into the fixed-dose combination products, where a topical antibiotic plus benzoyl peroxide, a retinoid plus benzoyl peroxide, or a retinoid plus a topical antibiotic each carry strong recommendations as well. The recurring theme is multiple mechanisms working together, not a single agent doing everything.

Why topical antibiotic monotherapy is discouraged

The guideline is unusually direct on one point: topical antibiotic monotherapy is not recommended. The reasoning is biological. Antibiotics applied alone create exactly the conditions that breed resistance, exposing skin bacteria to a selective pressure without any partner agent to suppress survivors. Over years of widespread use, that pattern has produced measurable resistance in C. acnes populations, which erodes the effectiveness of the whole antibiotic class for a condition that is common and often treated for months.

So the guideline does not remove topical antibiotics; it refuses to let them stand alone. Every strong recommendation involving an antibiotic is tethered to benzoyl peroxide or to a second mechanism. The clinical result and the stewardship goal converge: pairing improves acne outcomes and simultaneously protects the drug class. This is where the grading system does quiet work, because a therapy can be endorsed and constrained at the same time, and the letter grade captures only part of that nuance.

Stewardship written into the recommendations

Beyond the individual drugs, the guideline devotes several good practice statements to antibiotic stewardship as a standing design principle. It advises limiting systemic antibiotic use when possible to reduce both resistance and other antibiotic-associated complications. When an oral antibiotic is warranted, the guidance favors the shortest effective course, generally no longer than three to four months, and pairs it with benzoyl peroxide and other topical therapy so the systemic drug is never carrying the treatment alone. For topical regimens, it recommends combining agents with different mechanisms of action to optimize response and lower resistance risk.

Two features of these statements stand out. First, they are labeled good practice statements rather than graded recommendations, a GRADE category reserved for guidance so well grounded in indirect evidence and basic principle that a formal certainty rating would be misleading. Second, they treat oral isotretinoin as the reserved option for severe, scarring, or treatment-resistant disease, or where the psychosocial burden is high, keeping a powerful therapy positioned by need rather than convenience. Read together, the recommendations describe a hierarchy in which mechanism diversity and antibiotic restraint are built into the structure of care, not appended as afterthoughts.

For readers, the practical takeaway is a way of reading guidelines rather than a prescription. A strong recommendation signals confidence that the benefits outweigh the harms for most people; the certainty grade tells you how firm the evidence is; and remarks such as "not recommended as monotherapy" carry as much weight as the headline endorsement. This article is educational and not medical advice, and decisions about any specific treatment belong with a qualified clinician who knows the individual case.