内酰胺酶抑制剂抗生素（英文ppt）lactam

Miscellaneous Antibiotics Polymyxins nActive against gram-negative including pseudomonas. nPolymyxin B is only available. nBactericidal inhibits cell wall synthesis. nUsed only topically . nHighly nephrotoxic. Spectinomycin nBactericidal ,inhibits protein synthesis by binding to 30S ribosomal subunits. nActive against gram positive & gram negative organisms. nRapidly absorbed after intramuscular injection. nExcreted through kidney . Clinical uses nAs an alternative treatment for drug- resistant gonorrhea or gonorrhea in penicillin allergic patients. nNo cross-resistance with other drugs used in gonorrhea. n A single intramuscular dose is given Adverse effects nPain at the site of injection nFever And nausea nNephrotoxicity ( rare ) Clindamycin nActive against gram-positive cocci nGram negative anaerobic organisms nInhibits protein synthesis by binding to 50S ribosomal subunits. Pharmacokinetics nGiven orally or intravenously nHighly bound to plasma proteins nDistributes well into all body fluids & tissues except brain &CSF. nPenetrates well into abscess & is taken up by phagocytic cells. nMetabolized by the liver. nBoth active drug & active metabolites are excreted in bile & urine nNo dosage adjustment is needed for renal failure. Clinical uses nSevere anaerobic infections ( bones and joints) . nConjunctivitis. nIn combination with aminoglycoside or cephalosporin to treat penetrating wounds of the abdomen & the gut. nInfections in female genital tract ( septic abortion ,pelvis abscess ). nFor prophylaxis of endocarditis in patients with valvular heart disease nPlus primaquine is an effective alternative to co-trimoxazole for moderate or severe pneumocystis jiroveci pneumonia in AIDS patients Adverse Effects nDiarrhea , nausea, Skin rash nAntibiotic-associated colitis nImpaired liver function nNeutropenia ( not common ) Vancomycin nBactericidal nInhibits bacterial cell wall synthesis nActive on gram-positive bacteria including -lactamase producer & those resistant to methicillin. Pharmacokinetics nPoorly absorbed from GIT nSlow IVI is used for treatment of systemic infections. nWidely distributed nCerebrospinal fluid levels are achieved in meningeal inflammation nExcreted mainly through renal route Clinical uses nEndocarditis or sepsis mainly caused by methicillin resistant staphylococci. nAlternative to penicillin in enterococcal endocarditis( in combination with gentamicin). nMeningitis( in combination with cephalosporin) nOrally only for the treatment of antibiotic - associated enterocolitis Adverse effects nPhlebitis at the site of infusion nFever nOtotoxicity & nephrotoxicity ( not common). nRed man or red neck syndrome. nHypotension Bacitracin nBactericidal nInhibits cell wall synthesis nActive against gram +ve organisms nUsed only topically in skin ,eye ,nose infections . nAs ointment in combination with polymyxin or neomycin for mixed bacterial infections. nAs solution in saline for irrigation of joints, wounds or pleural cavity. Adverse Effects nHighly nephrotoxic producing proteinuria, hematuria nHypersensitivity reactions Teicoplanin nSimilar to vancomycin in : Mechanism of action Antibacterial activity nGiven I.M. or I.V. n long half-life(45-70 h). once daily. Cycloserine nBactericidal nInhibits bacterial cell wall nEffective on gram- positive & gram- negative organisms as well as M.tuberculosis. nRapidly absorbed orally nWidely distributed in body tissues & fluids. nExcreted as active form in urine