Ampicillin Trihydrate

Also known as: Principen, Omnipen, Polycillin, Penbritin

CAS Number: 7177-48-2

Aminopenicillin — broad-spectrum beta-lactam antibiotic

Pharmacopeia Standards

USPBPIP

Mechanism of Action

Binds irreversibly to penicillin-binding proteins (PBPs), blocking the transpeptidation step in peptidoglycan cross-linking. Bactericidal. Active against penicillin-sensitive gram-positive cocci and selected gram-negative rods (Haemophilus influenzae, E. coli, Proteus mirabilis). Susceptible to beta-lactamase hydrolysis.

Technical Specifications

Generic / INN Name	Ampicillin Trihydrate
CAS Registry Number	7177-48-2
Molecular Formula	C16H19N3O4S·3H2O
Molecular Weight	403.45 g/mol
Typical Purity	98.0–102.0% (anhydrous basis)
Storage Conditions	Store below 30°C in a dry place
Shelf Life	24 months from date of manufacture
Category	Penicillins

Specifications are indicative and intended for sourcing reference only. Always confirm against the supplier's Certificate of Analysis and the applicable pharmacopeial monograph before issuing a purchase specification.

Typical Applications

Respiratory tract infections (H. influenzae, S. pneumoniae), UTIs, meningitis (with gentamicin — neonatal/gram-negative), biliary tract infections, bacterial endocarditis prophylaxis, typhoid fever (historical), intra-abdominal infections (with sulbactam).