Orthopaedic and Trauma Medicine PHARMACOLOGY II Year: 2022 Semester: 2 Session 4

Lincosamides Lincomycin  Isolated from streptomyces lincolensis  Mechanism of action – binds to 50S ribosomal subunit  It is bacteriostatic Pharmacokinetics • Can be given orally or parenterally • Incomplete absorptionin git and food delays absorption • Rapid absorption with parenteral administration • Good distributioninbody tissues including bone • Metabolismis mainly in the liver • Excretionis through the kidneys, 30% unchanged Antibacterial spectrum • Highly effective against Gram positive organism especially staph aureus, beta haemolytic streptococcus, pneumococci and bacteroides • Good for skin and bone infections Adverse effects • Antibiotic associated diarrhoea • Nausea and vomiting Preparations • Syrups, capsules IM and IV • Dose 500mg tdsorally for adults • Children 30-60mg/kg in divided doses • Parenteral –Adult 600mg BD or TDS -Children 10mg/kg in divided doses Clindamycin • Synthetic form with similar properties to lincomycin • HCL group confers more efficacy • It is bacteriostatic, higher doses make it bactericidal • Antibacterial spectrum –Gram positive organisms; Staph aureus, Strep pyogenes, Strep viridans • It does not cover for MRSA • Methicillin-resistant Staphylococcus aureus (MRSA) is a cause of staph infection that is difficult to treat because of resistance to some antibiotics.