Cephalexin Monohydrate

Also known as: Keflex, Keftab, Zartan, Ceporex, Sporidex

CAS Number: 23325-78-2

1st generation cephalosporin — oral

Pharmacopeia Standards

USPBPIP

Mechanism of Action

First-generation beta-lactam cephalosporin that inhibits bacterial cell wall synthesis by binding PBP-1a, PBP-1b, and PBP-3. Stable to staphylococcal penicillinase. Active against S. aureus (MSSA), Streptococcus species, and limited gram-negative organisms (E. coli, Proteus mirabilis, Klebsiella pneumoniae susceptible strains). Oral, acid-stable.

Technical Specifications

Generic / INN Name	Cephalexin Monohydrate
CAS Registry Number	23325-78-2
Molecular Formula	C16H17N3O4S·H2O
Molecular Weight	365.41 g/mol
Typical Purity	97.5–102.0% (anhydrous basis)
Storage Conditions	Store below 25°C in a dry place, protect from moisture
Shelf Life	36 months from date of manufacture
Category	Cephalosporins

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

Skin and soft tissue infections (cellulitis, impetigo, folliculitis, furuncles), mild urinary tract infections, streptococcal pharyngitis (penicillin-alternative), bone/joint infections (oral step-down), surgical prophylaxis (minor procedures), otitis media, Staphylococcal infections in penicillin-allergic patients.