Pharmacology: Pharmacodynamics: Clindamycin belongs to the antibiotics of the group of linzamides. Suppresses protein synthesis in a microbial cell, interacting with 50S subunits of ribosomes. With local intravaginal application, clindamycin phosphate is hydrolyzed to clindamycin, which exhibits antibacterial activity. Clindamycin is active in vitro against the following registered strains of microorganisms associated with bacterial vaginosis: Bacteroides spp., Gardnerella vaginalis, Mobiluncus spp., Mycoplasma hominis, Peptostreptococcus spp.
The data of the original clindamycin on the susceptibility of bacteria associated with bacterial vaginosis. (See table.)

There is evidence of cross-resistance between clindamycin and lincomycin.
There is evidence of antagonism between clindamycin and erythromycin in vitro. Clinical significance of these data is unknown.
Pharmacokinetics: Clindamycin phosphate is rapidly hydrolyzed in the body with the formation of clindamycin, which exhibits antibacterial activity. Studies of the original clindamycin showed approximately 30% (6-70%) of the drug penetrates into the systemic circulation by intravaginal administration. The mean area under the curve (AUC) after three-day use of suppositories was 3.2 μg·h/ml (from 0.42 to 11 μg·h/ml). The maximum concentration in the blood is observed on day 3 for 5 hours (within 1 to 10 hours) after the use of suppositories and is on average 0.27 μg/ml (0.03-0.67 μg/ml). The average half-life after the use of suppositories is 11 hours (within 4 to 35 hours), it is believed that it is limited by the rate of absorption. The systemic absorption of clindamycin in the form of suppositories is 7 times higher than with the use of a similar dose of clindamycin in the form of a vaginal cream. In general, the systemic effect of clindamycin in the form of vaginal suppositories is 2-20 times lower than the therapeutic dose of oral clindamycin hydrochloride and 40-50 times lower than the therapeutic dose of parenteral clindamycin phosphate.