Description
Mechanism of Action
Ampicillin exerts bactericidal action on both gm+ve and gm-ve organisms. Its spectrum includes gm+ve organisms eg, S pneumoniae and other Streptococci, L monocytogenes and gm-ve bacteria eg, M catarrhalis, N gonorrhoea, N meningitidis, E coli, P mirabilis, Salmonella, Shigella, and H influenzae. Ampicillin exerts its action by inhibiting the synthesis of bacterial cell wall.
Absorption: Relatively well absorbed from the GI tract with peak plasma concentrations after 1-2 hr (oral); may be altered in the presence of food.
Distribution: Widely distributed into the ascitic, pleural and joint fluids (therapeutic concentrations), CSF (small amounts except when the meninges are inflamed), bile (high concentrations); crosses the placenta and enters the breast milk (small amounts). Protein-binding: 20%.
Metabolism: Converted to some extent to penicilloic acid; undergoes enterohepatic recycling.
Excretion: Via the urine by glomerular filtration and tubular secretion; via the faeces. May be removed by haemodialysis.
MIMS Class
Penicillins
ATC Classification
S01AA19 – ampicillin; Belongs to the class of antibiotics. Used in the treatment of eye infections.;
J01CA01 – ampicillin; Belongs to the class of penicillins with extended spectrum. Used in the systemic treatment of infections.;
