First generation cephalosporins are active against-

Ans. is 'b' i.e., Gram positive bacteria First generationSecond generationThird generationFourth generationo Active against gram positive organisms,o Cefazolin is the DOC for surgical prophylaxiso More active against gram negative organismso Also has some activity against gram (+)ve.o Some members are active against anaerobes.o Cefuroxime attains relatively higher CSF levels (But ceftriaxone, a 3rd generation drug has max. CSF penetration).o Have highly augmented activity against gram negative enterobateriaceaeo Less active against gram (+)ve cocci and anaerobeso Highly resistant to b-lactamases from gram negative bacteria,o Ceftazidim and cefopera- zone are active against pseudomonas.o Ceftriaxone is DOC for gonorrhoeao Ceftazidime + gentamycin is the treatment of choice for pseudomonas.o Ceftriaxone has best CSF penetration among cephalosporinso Ceftazidime is the drug of choice for melioidosis,o Ceftriaxone is the DOC for gonorrhoea, E.coli sepsis, proteus, serratia, salmonellosis and emperical therapy for bacterial meningitis,o Ceftizoxime has maximum activity against bacteroids.o Cefotaxime is metabolized to an active metabolite (desacetyl - cefotaxime).o Antibacterial spectrum is similar to 3rd genration compounds, but are highly resistant to b-lactamases,o Also have some activity against gram (+)ve (in contrast with 3rd generation)o Cefepime inhibits pseudomonas