Penicillin

1) aminopenicillin ( amoxicillin ) 
2) piperacillin 
3) ticarcillin 
                  broad spectrum of activity gram- and gram+, but gram- can develop resistence rapidly to penicillin by producing the enzyme B-lactimase .

                  amoxicillin + clavulinic acid = augmentin to decrease gram- resistenve ..

                  all of the penicillin are active against strepto ( gram+ ) but not staph ( gram+ ) because staph has penicillinase enzyme that destruct these types of penicillin .the only type are active against penicilline is called penicillinase resistence include ( methicillin , oxacillin ) 


     mainly used for skin infection 
   important side effect is allergy