A patient may also not respond to antibiotics therapy if there is P. acnes resistance (75). Antibiotic resistance is a real problem of growing concern. The overall incidence of P. acnes antibiotic resistance increased from about 20% in 1978 to approximately 62% in 1996. Resistance of P. acnes is most common for erythromycin, clindamycin, tetracycline, doxycycline, and trimethoprim. Minocycline resistance is present in about 1% of patients today (76). There is no resistance to benzoyl peroxide, azeleic acid, or sulfur.
Several things can be done to minimize selection, and spread of antibiotic resistant strains of P. acnes. Antibiotics should be used judiciously, and only until control is achieved. The antibiotic should then be discontinued. If repeat treatment with antibiotics is required, the same antibiotic should be reused (unless it has lost efficacy). Patients who
are on oral or topical antibiotics should also use a benzoyl peroxide product to reduce the numbers of antibiotic resistant organisms. Oral, and topical antibiotics with dissimilar properties should not be used concomitantly, as combining these agents may cause cross resistance. Patient education is important to maximize compliance and prevent resistance.