Erythrasma Cream or Tablets: What Two Trials Measured

A cream and an oral antibiotic can both appear on a treatment list for erythrasma. Choosing between them takes more than finding the largest percentage in a study summary.

Erythrasma is a bacterial infection caused by Corynebacterium minutissimum. It commonly affects skin folds and toe webs, and can resemble or coexist with a fungal rash. A Wood lamp may show coral-pink fluorescence; swabs or scrapings can also support diagnosis. A treatment comparison for confirmed erythrasma does not tell you what to use on an unidentified fold rash.¹

The Danish trial combined cure and improvement

A 1991 double-blind study² included 86 patients, 71 men and 15 women, in Danish general practice. For 14 days, participants received erythromycin tablets plus placebo cream, fusidic acid cream plus placebo tablets, or both placebos.²

The researchers assessed color, borders, scaling and Wood-lamp fluorescence before treatment, after one and two weeks, and at a follow-up four weeks later. The abstract reported cure or improvement in:²

Treatment	Cure or improvement
Erythromycin tablets	77%
Fusidic acid cream	87%
Placebo	42%

Both active treatments significantly outperformed placebo. The active treatments did not differ significantly from each other. The numerical difference does not demonstrate that the cream was better.²

The combined outcome also means that 87% cannot be relabeled as “completely cured.” The mostly male sample limits conclusions specifically about women.²

The 151-patient trial measured the lamp signal

A 2013 publication reported a randomized, double-blind, placebo-controlled study of 151 adults. Five groups received clarithromycin, erythromycin, fusidic acid cream, placebo cream or placebo tablets. Researchers compared Wood-lamp reflection scores on days 2, 7 and 14 with starting values.³

Fusidic acid cream produced significantly better results on that measure than the other treatments. Clarithromycin was significantly more effective than erythromycin at 48 hours, but the two oral treatments did not differ significantly on days 7 and 14.³

That timing matters. The early result does not establish that clarithromycin remains superior two weeks later. Likewise, a fluorescence score should retain its name when reporting the study; it is not a direct measure of itch, comfort or months without recurrence.

These findings concern the named medicines under study conditions. They do not show that any antibiotic cream will outperform any oral antibiotic.

What the later review could conclude

A 2025 systematic review, covering research from 1971 through 2024, found support for several topical treatments, including fusidic acid and clotrimazole. It also identified a shortage of large randomized trials using standardized outcomes. That limits a firm ranking across treatments.⁴

DermNet¹ lists topical treatments for erythrasma and oral antibiotics for extensive infection. It also notes that recurrence is common. A successful short course and prevention of future episodes are therefore separate matters to discuss.¹

The prescription needs a finish date

The UK Fucidin 20 mg/g cream information, revised in June 2026, includes erythrasma among its indications. It warns that extended or repeated use can increase antibiotic resistance and contact sensitization. Having a tube left over is not a reason to restart it each time a patch appears. Ask about the exact product, duration and what should prompt reassessment.⁵

Oral treatment requires an interaction check. NHS⁶ guidance specifically names simvastatin, atorvastatin, warfarin and colchicine, among other medicines, as needing review with clarithromycin. Give the clinician or pharmacist the full list, including supplements; do not adjust those medicines yourself to accommodate an antibiotic.⁶

At follow-up, describe what changed: the extent of the patch, scaling, itching and any new irritation. Ask whether the diagnosis needs another look if the rash persists or returns, rather than assuming it needs a longer antibiotic course.

Skin, Head to Toe, Chapter 9’s “The Folds,” discusses erythrasma, the Wood-lamp clue and its resemblance to other fold changes. That context can help describe a patch for examination; treatment choice still depends on the diagnosis and your circumstances.