Cephalexin
Cephalexin. First-generation cephalosporin β-lactam — inhibits transpeptidase (PBPs) blocking peptidoglycan crosslinking in bacterial cell… Oral half-life 0.8 h.
First-generation cephalosporin β-lactam — inhibits transpeptidase (PBPs) blocking peptidoglycan crosslinking in bacterial cell walls. Renally cleared unchanged; no CYP. Common for skin / urinary tract infections; ~10% cross-reactivity in penicillin-allergic patients.
PK: its source_pmid was a SYSTEMATIC REVIEW — secondary literature used as both the source and the only reference, reporting no pharmacokinetic parameter of its own. All four values were zero-content, and its ka 1.5 and V 18 L are byte-identical to LANSOPRAZOLE, an unrelated benzimidazole; since that record 18 is independently explained as its own subject count, the seed came from there. Half-life re-sourced to 0.80 h. NO HUMAN VOLUME AND NO ABSOLUTE BIOAVAILABILITY EXIST in any abstract — the only volumes found are in calves and cats. ABSORPTION IS CARRIER-MEDIATED THROUGH PEPT1 AND SATURABLE, so a constant rate is structurally wrong: a co-administered drug shifts exposure by 38%. TWO TRAPS LOGGED on the replacement paper. It lists cefaclor FIRST and cephalexin SECOND in every pair ("0.58 ... and 0.80 ... h"), so reading position one gives the wrong drug half-life; and its "0.88 h-1" is an ELIMINATION constant that must never migrate into an absorption slot.
Pharmacokinetics
- Oral — t½ 48 min
Sources: PMID:37760698, PMID:900915