Cefalexin

From Infogalactic: the planetary knowledge core
(Redirected from Cephalexin)
Jump to: navigation, search
Cefalexin
Cefalexin.svg
Cefalexin ball-and-stick.png
Systematic (IUPAC) name
(7R)-3-Methyl-7- (α- D -phenylglycylamino) -3-cephem-4-carboxylic acid monohydrate
Clinical data
Pronunciation /ˌsɛfəˈlɛksn/
Trade names Keflex, Cepol, Ceporex, others[1]
AHFS/Drugs.com monograph
MedlinePlus a682733
Licence data US FDA:link
Pregnancy
category
  • AU: A
  • US: B (No risk in non-human studies)
Legal status
  • AU: S4 (Prescription only)
  • UK: POM (Prescription only)
  • US: ℞-only
Routes of
administration
Oral
Pharmacokinetic data
Bioavailability Well absorbed
Protein binding 15%
Metabolism 80% excreted unchanged in urine within 6 hours of administration
Biological half-life For an adult with normal renal function, the serum half-life is 0.5–1.2 hours[2]
Excretion Renal
Identifiers
CAS Number 15686-71-2 YesY
ATC code J01DB01 (WHO) QJ51DB01 (WHO)
PubChem CID: 2666
IUPHAR/BPS 4832
DrugBank DB00567 YesY
ChemSpider 25541 YesY
UNII 5SFF1W6677 YesY
KEGG D00263 YesY
ChEBI CHEBI:3534 YesY
ChEMBL CHEMBL1727 YesY
Chemical data
Formula C16H17N3O4S
Molecular mass 347.39 g/mol
  • O=C2N1/C(=C(\CS[C@@H]1[C@@H]2NC(=O)[C@@H](c3ccccc3)N)C)C(=O)O
  • InChI=1S/C16H17N3O4S/c1-8-7-24-15-11(14(21)19(15)12(8)16(22)23)18-13(20)10(17)9-5-3-2-4-6-9/h2-6,10-11,15H,7,17H2,1H3,(H,18,20)(H,22,23)/t10-,11-,15-/m1/s1 YesY
  • Key:ZAIPMKNFIOOWCQ-UEKVPHQBSA-N YesY
Physical data
Melting point 326.8 °C (620.2 °F)
  (verify)

Cefalexin, also spelled cephalexin, is an antibiotic that can treat a number of bacterial infections. It kills gram-positive and some gram-negative bacteria by disrupting the growth of the bacterial cell wall. Cefalexin is a beta-lactam antibiotic within the class of first-generation cephalosporins.[3] It works similarly to other agents within this class, including intravenous cefazolin, but can be taken by mouth.[4]

Cefalexin can treat certain bacterial infections, including those of the middle ear, bone and joint, skin, and urinary tract. It may also be used for certain types of pneumonia, strep throat, and to prevent bacterial endocarditis. Cefalexin is not effective against infections caused by methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus, or Pseudomonas. Like other antibiotics, cefalexin cannot treat viral infections, such as the flu, common cold or acute bronchitis. Cefalexin can be used in those who have mild or moderate allergies to penicillin. However, it is not recommended in those with severe penicillin allergies.[3]

Common side effects include upset stomach and diarrhea.[3] An allergic reaction and infection with Clostridium difficile, a type of diarrhea, is also possible.[3] To date, no evidence of harm to the baby has been found when used during pregnancy[3][5] or breast feeding.[6] It can be used in children and those over 65 years of age. Those with kidney problems may require a decrease in dose.[3]

In 2012, cefalexin was one of the top 100 most prescribed medications in the United States.[7] In Canada, it was the 5th most common antibiotic used in 2013.[8] In Australia, it is one of the top 15 most prescribed medications.[9] Cefalexin was developed in 1967[10] and first marketed in 1969 and 1970 by a number of companies, including Glaxo Wellcome and Eli Lilly and Company under the names Keflex and Ceporex, among others.[1][11] Generic drug versions are available under several other trade names and are inexpensive.[3][12] Cefalexin is on the World Health Organization's List of Essential Medicines, the most important medications needed in a health system.[13]

Medical uses

A course of cefalexin capsules, commonly prescribed for infections

Cefalexin can treat a number of bacterial infections including: otitis media, streptococcal pharyngitis, bone and joint infections, pneumonia, cellulitis, and urinary tract infections.[3] It may be used to prevent bacterial endocarditis.[3] It can also be used for the prevention of recurrent urinary-tract infections.[14]

Cefalexin does not treat methicillin-resistant Staphylococcus aureus infections.[14]

Cefalexin is a useful alternative to penicillins in patients with penicillin intolerance. For example, penicillin is the treatment of choice for respiratory tract infections caused by Streptococcus, but cefalexin may be used as an alternative in penicillin-intolerant patients.[15] Caution must be exercised when administering cephalosporin antibiotics to penicillin-sensitive patients, because cross sensitivity with beta-lactam antibiotics has been documented in up to 10% of patients with a documented penicillin allergy.[16]

Pregnancy and breastfeeding

It is pregnancy category B in the United States and category A in Australia, meaning that no evidence of harm has been found after being taken by many pregnant women.[3][5] Use during breast feeding is generally safe.[6]

Adverse effects

The most common adverse effects of cefalexin, like other oral cephalosporins, are gastrointestinal (stomach area) disturbances and hypersensitivity reactions. Gastrointestinal disturbances include nausea, vomiting, and diarrhea, diarrhea being most common.[17] Hypersensitivity reactions include skin rashes, urticaria, fever, and anaphylaxis.[18] Pseudomembranous colitis and Clostridium difficile has been reported with use of cefalexin.[18]

Signs and symptoms of an allergic reaction include rash, itching, swelling, trouble breathing, or red, blistered, swollen, or peeling skin. Overall, cefalexin allergy occurs in less than 0.1% of patients, but it is seen in 1% to 10% of patients with a penicillin allergy.[19]

Interactions

Like other β-lactam antibiotics, renal excretion of cefalexin is delayed by probenecid.[20] Alcohol consumption does not have a negative interaction with cefalexin,[21] but reduces the rate at which it is absorbed.[22] Cefalexin also interacts with metformin, an antidiabetic drug,[18] and this can lead to higher concentrations of metformin in the body.[18][23]

Mechanism of action

Cefalexin is a beta-lactam antibiotic of the cephalosporin family.[24] It is bactericidal and acts by inhibiting synthesis of the peptidoglycan layer of the bacterial cell wall.[25] As cefalexin closely resembles d-alanyl-d-alanine, an amino acid ending on the peptidoglycan layer of the cell wall, it is able to irreversibly bind to the active site of PBP, which is essential for the synthesis of the cell wall.[25] It is most active against gram-positive cocci, and has moderate activity against some gram-negative bacilli.[26] However, some bacterial cells have the enzyme β-lactamase, which hydrolyzes the beta-lactam ring, rendering the drug inactive. This contributes to antibacterial resistance towards cephalexin.[27]

Society and culture

Cefalexin is on the World Health Organization's List of Essential Medicines, the most important medications needed in a health system.[13] The World Health Organization classifies cephalexin as a highly important antimicrobial in their list of Critically Important Antimicrobials for Human Medicine.[28]

Names

Cefalexin is the INN and BAN while cephalexin is the USAN and AAN.

Common brand names for cefalexin include Keflex, Cepol, Ceporexine, Ceporex, Cefadal, Derantel, Mecilex, Medoxine, Sporibest (Bionova), Xahl, and Tokiolexin.[29]

References

  1. 1.0 1.1 Lua error in package.lua at line 80: module 'strict' not found.
  2. McEvoy, G.K. (ed.). American Hospital Formulary Service — Drug Information 95. Bethesda, MD: American Society of Hospital Pharmacists, Inc., 1995 (Plus Supplements 1995)., p. 166
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. 5.0 5.1 Lua error in package.lua at line 80: module 'strict' not found.
  6. 6.0 6.1 Lua error in package.lua at line 80: module 'strict' not found.
  7. Lua error in package.lua at line 80: module 'strict' not found.
  8. Lua error in package.lua at line 80: module 'strict' not found.
  9. Lua error in package.lua at line 80: module 'strict' not found.
  10. Lua error in package.lua at line 80: module 'strict' not found.
  11. Lua error in package.lua at line 80: module 'strict' not found.
  12. Lua error in package.lua at line 80: module 'strict' not found.
  13. 13.0 13.1 Lua error in package.lua at line 80: module 'strict' not found.
  14. 14.0 14.1 Lua error in package.lua at line 80: module 'strict' not found.
  15. Lua error in package.lua at line 80: module 'strict' not found.
  16. Lua error in package.lua at line 80: module 'strict' not found.
  17. Lua error in package.lua at line 80: module 'strict' not found.
  18. 18.0 18.1 18.2 18.3 Lua error in package.lua at line 80: module 'strict' not found.
  19. Lua error in package.lua at line 80: module 'strict' not found.
  20. Lua error in package.lua at line 80: module 'strict' not found.
  21. Lua error in package.lua at line 80: module 'strict' not found.
  22. Lua error in package.lua at line 80: module 'strict' not found.
  23. Lua error in package.lua at line 80: module 'strict' not found.
  24. Lua error in package.lua at line 80: module 'strict' not found.
  25. 25.0 25.1 Lua error in package.lua at line 80: module 'strict' not found.
  26. Lua error in package.lua at line 80: module 'strict' not found.
  27. Lua error in package.lua at line 80: module 'strict' not found.
  28. Lua error in package.lua at line 80: module 'strict' not found.
  29. https://scifinder.cas.org

External links