7 DRUG INTERACTIONS • Clindamycin Phosphate and Benzoyl Peroxide Gel, 1.2%/5% should not be used in combination with erythromycin-containing products because of its clindamycin component. ( 7.1 ) 7.1 Erythromycin Avoid using Clindamycin Phosphate and Benzoyl Peroxide Gel, 1.2%/5% in combination with erythromycin-containing products due to its clindamycin component. In vitro studies have shown antagonism between erythromycin and clindamycin.
Source: FDA drug label - clindamycin, benzoyl peroxide