Cefalexin

Cefalexin

Clinical data
Pregnancy category	AU: A
Routes of administration	Oral
ATC code	J01DB01 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) UK: POM (Prescription only)
Pharmacokinetic data
Bioavailability	Well absorbed
Metabolism	90% excreted unchanged
Elimination half-life	0.9 hours
Excretion	Renal
Identifiers
IUPAC name 8-(2-amino-2-phenyl-acetyl)amino-4-methyl-7-oxo-2-thia-6-azabicyclo [4.2.0]oct-4-ene-5-carboxylic acid
CAS Number	15686-71-2
PubChem CID	2666
DrugBank	APRD00250
CompTox Dashboard (EPA)	DTXSID9022780
ECHA InfoCard	100.036.142
Chemical and physical data
Formula	C16H17N3O4S
Molar mass	347.39 g/mol g·mol−1

Cefalexin (INN) (Template:PronEng) or cephalexin (USAN) is a first-generation cephalosporin antibiotic. It is an orally-administered agent with a similar antimicrobial spectrum to the intravenous agents cefalotin and cefazolin. It is commonly marketed under the trade name Keflex (Lilly) or Sporidex (Ranbaxy).

Clinical use

Main article: Cephalosporin

Indications

Cefalexin is used to treat urinary tract infections, respiratory tract infections (including sinusitis, otitis media, pharyngitis, tonsillitis and pneumonia, bronchitis), skin and soft tissue infections.

Although it is not generally considered first-line therapy for any indication, it is a useful alternative to penicillins in patients with penicillin hypersensitivity. There is, however, cross-reactivity in 10% of patients with hypersensitivity to penicillins and carbapenems.

Formulations

Cefalexin is commonly marketed as tablets(250 mg and 500 mg), tablets, and powder for oral suspension (125 mg/5 mL and 250 mg/5 mL).

Cephalexin is being marketed as Keflex® 750 mg as "taken twice per day". The advantage of Keflex 750 is that it provides the same total daily dose most health care professionals prescribe with only two capsules per day. By making Keflex 750 convenient for patients, compliance may be improved with this new dosing option. Keflex 750 is covered by most major insurers with an average copay of between $20 and $25. Retail price is approximately $45 for a 20 capsule supply.

It is marketed by generic pharmaceutical manufacturers under a wide range of brand names, including: Apo-Cephalex, Biocef, Cefanox, Ceporex, Cephabos, Cilex, Ialex, Ibilex, Keflet, Keflex, Keforal, Keftab, Keftal, Lopilexin, Novo-Lexin, Ospexin, Zephalexin, Panixine Disperdose and Sporidex.

See also

• Cephalosporin
• Cefazolin

External links

• MedlinePlus Drug Information: Cephalosporins (systemic) – information from USP DI Advice for the Patient
• FDA Drug Information PDF and Pharmacy Drug Information Insert.