Table 3.
RCTs comparing topical erythromycin versus vehicle.
| Ref | Number of people | Treatment, dose, duration | Results | Comment |
| 160 people with mild to moderate acne | Erythromycin 2% alone v isotretinoin 0.05% alone v isotretinoin plus erythromycin v placebo, for 12 weeks | Overall severity: Erythromycin significantly reduced total lesions from baseline at 12 weeks whereas placebo did not (mean % change in count per person: –25%, 95% CI –39.04% to –11.44% with erythromycin v –10.82%, 95% CI –24.29% to +2.65% with placebo). Non-inflammatory lesions: No significant difference in non-inflammatory lesions from baseline within the erythromycin or the placebo group at 12 weeks (mean % change: –17%, 95% CI –38.07% to +4.63% with erythromycin; –7%, 95% CI –28.31% to +14.16% with placebo). Inflammatory lesions: Erythromycin significantly reduced inflammatory lesions from baseline within the group at 12 weeks whereas placebo did not (mean % reduction in count per person: –28%, 95% CI –41.29% to –14.14% with erythromycin v –10%, 95% CI –24.51% to +5.36% with placebo) Patient perception of improvement: Similar proportion of people taking erythromycin compared with vehicle perceived that their acne had improved from baseline at 12 weeks (58% with erythromycin v 53% with vehicle; significance of difference not assessed) Adverse effects: No data reported | Did not compare erythromycin alone versus placebo directly: assessed changes from baseline within the erythromycin and the placebo groups | |
| 225 people with mild to moderate acne | Erythromycin 2% twice daily v vehicle, for 12 weeks | Overall severity: Reduction in Cook's severity score at 12 weeks: –40 with erythromycin v –22 with vehicle; P = NS, CI not reportedNon-inflammatory lesions: No data reportedInflammatory lesions: Erythromycin significantly reduced inflammatory lesions at 12 weeks compared with vehicle (% reduction: –46% with erythromycin v –19% with vehicle; P = 0.01)Patient perception of improvement: No data reportedAdverse effects: No significant difference in erythema or peeling between erythromycin and vehicle (reported as non-significant, CI not reported). No other adverse effects assessed | ||
| 187 people with mild to moderate acne | Erythromycin 2% twice daily v vehicle, for 8 weeks | Overall severity: No data reportedNon-inflammatory lesions: Erythromycin significantly reduced open comedones compared with vehicle at 8 weeks (mean reduction in count per person: –7.5 with erythromycin v –4.6 with vehicle; P less than 0.01). No significant difference in closed comedones (mean reduction in count per person: –1.7 with erythromycin v –2.3 with vehicle; P = NS, CI not reported)Inflammatory lesions: Erythromycin significantly reduced papules from baseline (mean reduction in count: –6.2 with erythromycin v –4.3 with vehicle; P less than 0.01). No significant difference in pustules (mean reduction in count: –1.7 with erythromycin v –1.2 with vehicle; P = NS, CI not reported)Patient perception of improvement: No data reportedAdverse effects: Most frequently reported adverse effects were mild burning and peeling; no significant difference between erythromycin and vehicle | ||
| 175 people with moderate to severe acne unresponsive to oral tetracycline, topical benzoyl peroxide, or topical tretinoin | Erythromycin 2% twice daily v vehicle, for 12 weeks | Overall severity: Proportion of people rated by physician as having “excellent” or “good” response: 62% with erythromycin v 27% with vehicle; P less than 0.001Non-inflammatory lesions: No data reportedInflammatory lesions: Erythromycin significantly reduced total inflammatory lesion count at 12 weeks compared with vehicle (856 with erythromycin v 1338 with vehicle; P less than 0.01)Patient perception of improvement: No data reportedAdverse effects: Fewer people taking erythromycin had 1 or more adverse effects, including redness, scaling, dryness, and pruritis, compared with people taking vehicle (17/90 [19%] with erythromycin v 21/85 [25%] with vehicle; CI not reported). 2 people taking erythromycin withdrew because of adverse effects compared with 4 taking vehicle | Completer analysis in 156 people; no intention-to-treat analysis. People excluded from analysis for poor compliance and failure to complete treatment. Physician rating scale included “excellent”, “good”, “partially improved”, “not improved”, and “worse”. Unclear how ratings were measured | |
| 253 people with moderate to severe acne | Erythromycin 1.5% twice daily v vehicle, for 12 weeks | Overall severity: Erythromycin significantly reduced total lesion count at 12 weeks compared with vehicle (P = 0.01)Non-inflammatory lesions: No significant difference in open or closed comedones between erythromycin and vehicle (reported as NS, P value not reported)Inflammatory lesions: Erythromycin significantly reduced papules and pustules at 12 weeks compared with vehicle (P less than 0.025)Patient perception of improvement: No data reportedAdverse effects: 26 people in each group had 1 or more adverse effects, including erythema, scaling, tenderness, and dryness | Absolute results presented graphically | |
| 26 people with moderate to severe acne | Erythromycin 1.5% twice daily v vehicle, for 12 weeks | Overall severity: Erythromycin significantly increased the proportion of people rated by physician as having “excellent” or “good” response compared with vehicle (92% with erythromycin v 20% with vehicle; P = 0.005)Non-inflammatory lesions: Reported that erythromycin had less effect on comedones; no further data reportedInflammatory lesions: Erythromycin significantly reduced the proportion of people who had more than 50% reduction in papules at 12 weeks (11/12 [32%] with erythromycin v 4/10 [40%] with vehicle; P = 0.01) Patient perception of improvement: No data reportedAdverse effects: Reported that “no serious reactions to either formula were observed” | ||
| 28 people with moderate to severe acne | Erythromycin 1% twice daily v vehicle, for 4–8 weeks | Overall severity: No data reported Non-inflammatory lesions: No data reportedInflammatory lesions: In 21 people, erythromycin was more effective than vehicle in reducing inflammatory lesions at 8 weeks, in 4 people vehicle more effective, and in 3 no difference; P value not reportedPatient perception of improvement: No data reportedAdverse effects: No data reported | Split-face study | |
| 73 people with moderate to severe acne | Erythromycin 2% twice daily v vehicle, for 12 weeks | Overall severity: No data reportedNon-inflammatory lesions: No data reported Inflammatory lesions: No significant difference in the proportion of people who had more than 50% reduction in inflammatory lesions at 12 weeks between erythromycin and vehicle (30% with erythromycin v 20% with vehicle; reported as NS, P value not reported)Patient perception of improvement: No data reportedAdverse effects: No data reported | Split-face study |
NS, not significant; Ref, reference