» Erythromycin Ethylsuccinate Oral Suspension is a suspension of Erythromycin Ethylsuccinate containing one or more suitable buffers, colors, dispersants, flavors, and preservatives. It contains the equivalent of not less than 90.0 percent and not more than 120.0 percent of the labeled amount of erythromycin (C₃₇H₆₇NO₁₃).