Methyl 7-chloro-6,7,8-trideoxy-6-((hydroxy(1-methyl-4-propylpyrrolidin-2-yl)methylidene)amino)-1-thiooctopyranoside

Water soluble

3.10e+00 g/L

141-143C

142 °C (hydrochloride salt)

7.72

7.6

Oral; topical; parenteral (intramuscular, intravenous). Rapidly absorbed after oral administration with peak serum concentrations observed after about 45 minutes. Absorption of an oral dose is virtually complete (90%) and the concomitant intake of food does not appreciably modify the serum concentrations; serum levels have been uniform and predictable from person to person and dose to dose. Clindamycin does not penetrate the blood brain barrier.

Systemic/vaginal clindamycin inhibits protein synthesis of bacteria by binding to the 50S ribosomal subunits of the bacteria. Specifically, it binds primarily to the 23s RNA subunit. Topical clindamycin reduces free fatty acid concentrations on the skin and suppresses the growth of Propionibacterium acnes (Corynebacterium acnes) , an anaerobe found in sebaceous glands and follicles.

Orally and parenterally administered clindamycin has been associated with severe colitis (pseudomembranous colitis) which may result in patient death. Use of the topical formulation of clindamycin results in absorption of the antibiotic from the skin surface. Diarrhea, bloody diarrhea, and colitis (including pseudomembranous colitis) have been reported with the use of topical and systemic clindamycin.

Clindamycin exerts its bacteriostatic effect via inhibition of microbial protein synthesis. Clindamycin has a relatively short T_max and half-life necessitating administration every six hours to ensure adequate antibiotic concentrations. _Clostridium difficile_ associated diarrhea (CDAD) has been observed in patients using clindamycin, ranging in severity from mild diarrhea to fatal colitis and occasionally occurring over two months following cessation of antibiotic therapy. Overgrowth of _C. difficile_ resulting from antibiotic use, along with its production of A and B toxins, contributes to morbidity and mortality in these patients. Because of the associated risks, clindamycin should be reserved for serious infections for which the use of less toxic antimicrobial agents are inappropriate. Clindamycin is active against a number of gram-positive aerobic bacteria, as well as both gram-positive and gram-negative anaerobes. Resistance to clindamycin may develop, and is generally the result of base modification within the 23S ribosomal RNA. Cross-resistance between clindamycin and lincomycin is complete, and may also occur between clindamycin and macrolide antibiotics (e.g. [erythromycin]) due to similarities in their binding sites. As antimicrobial susceptibility patterns are geographically distinct, local antibiograms should be consulted to ensure adequate coverage of relevant pathogens prior to use.

Clindamycin inhibits bacterial protein synthesis by binding to 23S RNA of the 50S subunit of the bacterial ribosome. It impedes both the assembly of the ribosome and the translation process. The molecular mechanism through which this occurs is thought to be due to clindamycin's three-dimensional structure, which closely resembles the 3'-ends of L-Pro-Met-tRNA and deacylated-tRNA during the peptide elongation cycle - in acting as a structural analog of these tRNA molecules, clindamycin impairs peptide chain initiation and may stimulate dissociation of peptidyl-tRNA from bacterial ribosomes. The mechanism through which topical clindamycin treats acne vulgaris is unclear, but may be related to its activity against _Propionibacterium acnes_, a bacteria that has been associated with acne.