Description

Simple

An antibiotic used to treat a wide variety of infections in the body.

Clinical

A first generation cephalosporin used to treat certain susceptible bacterial infections.

Overview

Cephalexin is the first of the first generation cephalosporins.[7,8] This antibiotic contains a beta lactam and a dihydrothiazide.[7] Cephalexin is used to treat a number of susceptible bacterial infections through inhibition of cell wall synthesis.[9,Label] Cephalexin was approved by the FDA on 4 January 1971.[Read more

Pharmacology

Indication

Cephalexin is indicated for the treatment of certain infections caused by susceptible bacteria.[Label,12, Read more

Pharmacodynamic

Cephalexin (also called Cefalexin) is a first generation cephalosporin antibiotic.[ Read more

Mechanism of action

Cephalexin is a first generation cephalosporin antibiotic.[ Read more

Absorption

Well absorbed from the upper gastrointestinal tract with nearly 100% oral bioavailability.[ Read more

Protein binding

Cephalexin is 10-15% bound to serum proteins[Label,12] including serum albumin.[A179053]

Volume of distribution

5.2-5.8L.[6]

Clearance

Clearance from one subject was 376mL/min.[3]

Half life

The half life of cephalexin is 49.5 minutes in a fasted state and 76.5 minutes with food though these times were not significantly different in the study.[ Read more

Route of elimination

Cephalexin is over 90% excreted in the urine after 6 hours[ Read more

Toxicity

Symptoms of overdose include blood in the urine, diarrhea, nausea, upper abdominal pain, and vomiting.[Label] An overdose is generally managed through supportive treatment as diuresis, dialysis, hemodialysis, and charcoal hemoperfusion are not well studied in this case.[Label]

The oral median let... Read more

Adverse Effects

Contraindications

  • Hypersensitivity:
    • Cephalosporin Antibacterial
  • Regions: US

Food Interactions

  • Take with or without food.

Interactions

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  • Paracetamol(acetaminophen)
  • Paxil(paroxetine)
  • Pamelor(nortriptyline)
  • Panadol(acetaminophen)
  • Patanol(olopatadine ophthalmic)
  • Pataday(olopatadine ophthalmic)
  • Parnate(tranylcypromine)
  • Pazeo(olopatadine ophthalmic)
(R)-warfarin
The risk or severity of bleeding can be increased when Cephalexin is combined with (R)-warfarin.
(S)-Warfarin
The risk or severity of bleeding can be increased when Cephalexin is combined with (S)-Warfarin.
4-hydroxycoumarin
The metabolism of 4-hydroxycoumarin can be decreased when combined with Cephalexin.
6-Deoxyerythronolide B
The metabolism of Cephalexin can be decreased when combined with 6-Deoxyerythronolide B.
7-ethyl-10-hydroxycamptothecin
The metabolism of Cephalexin can be decreased when combined with 7-ethyl-10-hydroxycamptothecin.
9-aminocamptothecin
The metabolism of 9-aminocamptothecin can be decreased when combined with Cephalexin.
Abacavir
Cephalexin may decrease the excretion rate of Abacavir which could result in a higher serum level.
Abatacept
The metabolism of Cephalexin can be increased when combined with Abatacept.
Abciximab
The therapeutic efficacy of Abciximab can be decreased when used in combination with Cephalexin.
Abemaciclib
The excretion of Abemaciclib can be decreased when combined with Cephalexin.
Acalabrutinib
The metabolism of Cephalexin can be decreased when combined with Acalabrutinib.
Acarbose
Cephalexin may decrease the excretion rate of Acarbose which could result in a higher serum level.
Aceclofenac
Cephalexin may decrease the excretion rate of Aceclofenac which could result in a higher serum level.
Acemetacin
Acemetacin may decrease the excretion rate of Cephalexin which could result in a higher serum level.
Acenocoumarol
The metabolism of Acenocoumarol can be decreased when combined with Cephalexin.
Acetaminophen
Cephalexin may decrease the excretion rate of Acetaminophen which could result in a higher serum level.
Acetazolamide
The metabolism of Cephalexin can be decreased when combined with Acetazolamide.
Acetylcysteine zinc
Acetylcysteine zinc can cause a decrease in the absorption of Cephalexin resulting in a reduced serum concentration and potentially a decrease in efficacy.
Acetylsalicylic acid
Cephalexin may decrease the excretion rate of Acetylsalicylic acid which could result in a higher serum level.
Aclidinium
Cephalexin may decrease the excretion rate of Aclidinium which could result in a higher serum level.
13 References
  1. 1 . Thornhill TS, Levison ME, Johnson WD, Kaye D: In vitro antimicrobial activity and human pharmacology of cephalexin, a new orally absorbed cephalosporin C antibiotic. Appl Microbiol. 1969 Mar;17(3):457-61.PubMed: 4388601
  2. 2 . Sullivan HR, Billings RE, McMahon RE: Metabolism of cephalexin-14C in mice and in rats. J Antibiot (Tokyo). 1969 May;22(5):195-200.PubMed: 5811391
  3. 3 . Gower PE, Dash CH: Cephalexin: human studies of absorption and excretion of a new cephalosporin antibiotic. Br J Pharmacol. 1969 Nov;37(3):738-47. doi: 10.1111/j.1476-5381.1969.tb08513.x.PubMed: 5348475
  4. 4 . Henning C, Kallings LO, Lidman K, Sterner G: Studies of absorption, excretion, antibacterial and clinical effect of cephalexin. Scand J Infect Dis. 1970;2(2):131-8.PubMed: 4398634
  5. 5 . Griffith RS: The pharmacology of cephalexin. Postgrad Med J. 1983;59 Suppl 5:16-27.PubMed: 6364086
  6. 6 . Pfeffer M, Jackson A, Ximenes J, de Menezes JP: Comparative human oral clinical pharmacology of cefadroxil, cephalexin, and cephradine. Antimicrob Agents Chemother. 1977 Feb;11(2):331-8. doi: 10.1128/aac.11.2.331.PubMed: 848940
  7. 7 . Tanrisever B, Santella PJ: Cefadroxil. A review of its antibacterial, pharmacokinetic and therapeutic properties in comparison with cephalexin and cephradine. Drugs. 1986;32 Suppl 3:1-16. doi: 10.2165/00003495-198600323-00003.PubMed: 3542485
  8. 8 . Sader HS, Jacobs MR, Fritsche TR: Review of the spectrum and potency of orally administered cephalosporins and amoxicillin/clavulanate. Diagn Microbiol Infect Dis. 2007 Mar;57(3 Suppl):5S-12S. doi: 10.1016/j.diagmicrobio.2006.12.014. Epub 2007 Feb 9.PubMed: 17292577
  9. 9 . Fisher JF, Meroueh SO, Mobashery S: Bacterial resistance to beta-lactam antibiotics: compelling opportunism, compelling opportunity. Chem Rev. 2005 Feb;105(2):395-424. doi: 10.1021/cr030102i.PubMed: 15700950
  10. 10 . Cephalexin Product Monograph Link
  11. 11 . FDA Approved Drug Products: Cephalexin Oral Capsule Link
  12. 12 . FDA Approved Drug Products: Cephalexin Oral Suspension Link
  13. 13 . FDA Approved Drug Products: Cephalexin Oral Tablet Link