Clindamycin is a lincosamide antibiotic derived from lincomycin, used primarily for the treatment of serious anaerobic and Gram-positive aerobic bacterial infections. It is a bacteriostatic agent that inhibits protein synthesis by binding to the 50S ribosomal subunit. In the Indian context, it is a critical drug for skin and soft tissue infections, dental infections, and as a prophylactic agent in specific surgeries, despite the growing challenge of bacterial resistance.
Adult: For serious infections: 150 to 300 mg every 6 hours. For severe infections: 300 to 450 mg every 6 hours. The 300mg strength is typically administered every 6-8 hours.
Note: Capsule/Tablet: Administer with a full glass of water to minimize esophageal irritation. Can be taken with or without food; food does not significantly impair absorption but may reduce gastrointestinal upset. Complete the full prescribed course even if symptoms improve.
Clindamycin binds reversibly to the 50S subunit of the bacterial ribosome, specifically at a site overlapping with the binding sites for macrolides and chloramphenicol. This binding inhibits the peptidyl transferase reaction during the early stages of protein synthesis, specifically the translocation of aminoacyl tRNA from the A-site to the P-site. This results in the suppression of bacterial protein synthesis.
Pregnancy: US FDA Pregnancy Category B. Animal studies show no risk, but no adequate, well-controlled studies in pregnant women. Use only if clearly needed. Crosses the placenta. Consider risk of CDAD.
Driving: Generally safe. However, dizziness or vertigo are rare side effects; patients should be cautioned.
| Erythromycin, Clarithromycin | Antagonism; compete for same ribosomal binding site, reducing efficacy of both. | Major |
| Kaolin-Pectin, Antacids (Al, Mg) | May decrease oral absorption of clindamycin. Administer clindamycin at least 2 hours before these agents. | Moderate |
| CYP3A4 Inducers (e.g., Rifampicin, Phenytoin, Carbamazepine) | May increase metabolism of clindamycin, reducing its plasma concentration and efficacy. | Moderate |
| CYP3A4 Inhibitors (e.g., Ketoconazole, Itraconazole) | May decrease metabolism of clindamycin, increasing its plasma concentration and risk of toxicity. | Moderate |
| Neuromuscular blocking agents (e.g., Pancuronium, Vecuronium) | Clindamycin may enhance neuromuscular blockade, leading to prolonged apnea or respiratory depression. | Major |
| Opioid antidiarrheals (e.g., Loperamide, Diphenoxylate/Atropine) | Contraindicated in CDAD; may delay toxin excretion and worsen colitis. | Major |
| Chloramphenicol | Possible antagonism; avoid concurrent use. | Moderate |