U.S. Department of Health & Human Services Divider Arrow National Institutes of Health Divider Arrow NCATS

Details

Stereochemistry ABSOLUTE
Molecular Formula C16H17N3O4S.H2O
Molecular Weight 365.404
Optical Activity UNSPECIFIED
Defined Stereocenters 3 / 3
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of CEPHALEXIN

SMILES

O.[H][C@]12SCC(C)=C(N1C(=O)[C@H]2NC(=O)[C@H](N)C3=CC=CC=C3)C(O)=O

InChI

InChIKey=AVGYWQBCYZHHPN-CYJZLJNKSA-N
InChI=1S/C16H17N3O4S.H2O/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);1H2/t10-,11-,15-;/m1./s1

HIDE SMILES / InChI

Molecular Formula C16H17N3O4S
Molecular Weight 347.389
Charge 0
Count
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 3 / 3
E/Z Centers 0
Optical Activity UNSPECIFIED

Molecular Formula H2O
Molecular Weight 18.0153
Charge 0
Count
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Cephalexin is a semisynthetic cephalosporin antibiotic intended for oral administration. In vitro tests demonstrate that the cephalosporins are bactericidal because of their inhibition of cell-wall synthesis. Cephalexin has been shown to be active against most strains of the following microorganisms both in vitro: Staphylococcus aureus (including penicillinase-producing strains), Streptococcus pneumoniae (penicillin-susceptible strains), Streptococcus pyogenes, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Moraxella (Branhamella) catarrhalis, Proteus mirabilis. Cephalexin is indicated for the treatment of the respiratory tract, skin and skin structure, bone and genitourinary tract infections when caused by susceptible strains of the designated microorganisms.

CNS Activity

Curator's Comment: Cephalexin is brain penetrant and neurotoxic in animals. No human data available.

Originator

Curator's Comment: # Eli Lilly

Approval Year

Targets

Targets

Primary TargetPharmacologyConditionPotency
Conditions

Conditions

ConditionModalityTargetsHighest PhaseProduct
Curative
KEFLEX

Approved Use

Cephalexin capsules are indicated for the treatment of the following infections when caused by susceptible strains of the designated microorganisms: Respiratory tract infections caused by Streptococcus pneumoniae and Streptococcus pyogenes (Penicillin is the usual drug of choice in the treatment and prevention of streptococcal infections, including the prophylaxis of rheumatic fever. Cephalexin capsules are generally effective in the eradication of streptococci from the nasopharynx; however, substantial data establishing the efficacy of cephalexin capsules in the subsequent prevention of rheumatic fever are not available at present.) Otitis media due to Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes , and Moraxella catarrhalis Skin and skin structure infections caused by Staphylococcus aureus and/or Streptococcus pyogenes Bone infections caused by Staphylococcus aureus and/or Proteus mirabilis Genitourinary tract infections, including acute prostatitis, caused by Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae Note — Culture and susceptibility tests should be initiated prior to and during therapy. Renal function studies should be performed when indicated. To reduce the development of drug-resistant bacteria and maintain the effectiveness of cephalexin and other antibacterial drugs, cephalexin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Launch Date

1971
Cmax

Cmax

ValueDoseCo-administeredAnalytePopulation
18.25 μg/mL
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: FASTED
126 mg/L
40 mg/kg 3 times / day multiple, oral
dose: 40 mg/kg
route of administration: Oral
experiment type: MULTIPLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: UNHEALTHY
age: CHILD
sex: UNKNOWN
food status: UNKNOWN
AUC

AUC

ValueDoseCo-administeredAnalytePopulation
31.22 μg × h/mL
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: FASTED
245 mg × h/L
40 mg/kg 3 times / day multiple, oral
dose: 40 mg/kg
route of administration: Oral
experiment type: MULTIPLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: UNHEALTHY
age: CHILD
sex: UNKNOWN
food status: UNKNOWN
T1/2

T1/2

ValueDoseCo-administeredAnalytePopulation
1.12 h
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: FASTED
Funbound

Funbound

ValueDoseCo-administeredAnalytePopulation
85%
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
CEPHALEXIN plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: FASTED
Doses

Doses

DosePopulationAdverse events​
40 mg/kg 3 times / day multiple, oral (median)
Dose: 40 mg/kg, 3 times / day
Route: oral
Route: multiple
Dose: 40 mg/kg, 3 times / day
Sources:
unhealthy, 1-16 years
n = 12
Health Status: unhealthy
Condition: Osteoarticular Infections
Age Group: 1-16 years
Sex: M+F
Population Size: 12
Sources:
Disc. AE: Neutropenia...
AEs leading to
discontinuation/dose reduction:
Neutropenia (1 patient)
Sources:
500 mg 2 times / day multiple, oral
Dose: 500 mg, 2 times / day
Route: oral
Route: multiple
Dose: 500 mg, 2 times / day
Sources:
unhealthy, 90 years
n = 1
Health Status: unhealthy
Age Group: 90 years
Sex: F
Population Size: 1
Sources:
Disc. AE: Tendonitis...
AEs leading to
discontinuation/dose reduction:
Tendonitis (1 patient)
Sources:
AEs

AEs

AESignificanceDosePopulation
Neutropenia 1 patient
Disc. AE
40 mg/kg 3 times / day multiple, oral (median)
Dose: 40 mg/kg, 3 times / day
Route: oral
Route: multiple
Dose: 40 mg/kg, 3 times / day
Sources:
unhealthy, 1-16 years
n = 12
Health Status: unhealthy
Condition: Osteoarticular Infections
Age Group: 1-16 years
Sex: M+F
Population Size: 12
Sources:
Tendonitis 1 patient
Disc. AE
500 mg 2 times / day multiple, oral
Dose: 500 mg, 2 times / day
Route: oral
Route: multiple
Dose: 500 mg, 2 times / day
Sources:
unhealthy, 90 years
n = 1
Health Status: unhealthy
Age Group: 90 years
Sex: F
Population Size: 1
Sources:
Overview

Overview

CYP3A4CYP2C9CYP2D6hERG

OverviewOther

Other InhibitorOther SubstrateOther Inducer



Drug as victim
Sourcing

Sourcing

Vendor/AggregatorIDURL
PubMed

PubMed

TitleDatePubMed
Encouraging good antimicrobial prescribing practice: a review of antibiotic prescribing policies used in the South East Region of England.
2001
Recurrent diarrhea associated with enterotoxigenic Clostridium perfringens in 2 dogs.
2001 Apr
Upper respiratory tract infections.
2001 Dec
Roles of Escherichia coli histone-like protein HU in DNA replication: HU-beta suppresses the thermosensitivity of dnaA46ts.
2001 Feb
Bioaugmentation and treatment of cephalexin drug-based pharmaceutical effluent in an upflow anaerobic fluidized bed system.
2001 Feb
Drug resistant Haemophilus influenzae from respiratory tract infection in a tertiary care hospital in north India.
2001 Jan-Mar
A rare case of primary group A streptococcal peritonitis.
2001 Jul
Special feature: picture of the month.
2001 Jun
Verotoxin-producing Escherichia coli--an environment-induced emerging zoonosis in and around Calcutta.
2001 Mar
Use of cephalosporins during pregnancy and in the presence of congenital abnormalities: a population-based, case-control study.
2001 May
Correlation between epithelial cell permeability of cephalexin and expression of intestinal oligopeptide transporter.
2001 Nov
[The use of veterinary drugs during pregnancy of the dog].
2001 Nov 15
CF and antistaphylococcal prophylaxis.
2001 Oct
Determination of cephalexin in oral suspensions by micellar electrokinetic chromatography.
2002
[Effect of peptide antibacterial factor and changes in Staphylococcus susceptibility to antibiotics].
2002
Moxifloxacin in uncomplicated skin and skin structure infections.
2002
The role of hydrophobic active-site residues in substrate specificity and acyl transfer activity of penicillin acylase.
2002 Apr
Prophylactic antibiotics in cirrhotics with upper gastrointestinal hemorrhage: a prospective, controlled trial.
2002 Aug
Localized lymphatic sporotrichosis after fish-induced injury (Tilapia sp.).
2002 Aug
Immunoglobulin E binding determinants on beta-lactam drugs.
2002 Aug
Shorter courses of parenteral antibiotic therapy do not appear to influence response rates for children with acute hematogenous osteomyelitis: a systematic review.
2002 Aug 14
Advantages of using non-isothermal bioreactors for the enzymatic synthesis of antibiotics: the penicillin G acylase as enzyme model.
2002 Aug 5
Solid state 'adsorption' of fine antibiotic powders onto sorbitol: effects of particle size, state of sorbed water and surface free energy characteristics.
2002 Dec
Orbital abscess following uncomplicated phacoemulsification cataract surgery.
2002 Dec
Enrofloxacin resistance in Escherichia coli isolated from dogs with urinary tract infections.
2002 Jan 15
[Pharmacokinetics of cephalexin from two oral formulations in dogs].
2002 Jan-Feb
Sensitivity and resistance of antibiotics in common infection of male and female.
2002 Jan-Mar
Update on prosthetic joints, dental treatment, and antibiotic prophylaxis.
2002 Jul
Community-acquired methicillin-resistant Staphylococcus aureus, Finland.
2002 Jun
Antibiotic prophylaxis in infants and young children with cystic fibrosis: a randomized controlled trial.
2002 Mar
Evaluation of UV-radiation induced singlet oxygen generation potential of selected drugs.
2002 May
Evaluation of the performance of immobilized penicillin G acylase using active-site titration.
2002 May 20
Risk of serious skin disorders among users of oral antifungals: a population-based study.
2002 Nov 28
Integrated reactor concepts for the enzymatic kinetic synthesis of cephalexin.
2002 Oct 20
Quantitative characterization of the nucleophile reactivity in penicillin acylase-catalyzed acyl transfer reactions.
2002 Sep 23
Patents

Sample Use Guides

Adults — The adult dosage ranges from 1 to 4 g daily in divided doses. The usual adult dose is 250 mg every 6 hours. For the following infections, a dosage of 500 mg may be administered every 12 hours: streptococcal pharyngitis, skin and skin structure infections, and uncomplicated cystitis in patients over 15 years of age. Cystitis therapy should be continued for 7 to 14 days. For more severe infections or those caused by less susceptible organisms, larger doses may be needed. If daily doses of Keflex greater than 4 g are required, parenteral cephalosporins, in appropriate doses, should be considered. Pediatric Patients — The usual recommended daily dosage for pediatric patients is 25 to 50 mg/kg in divided doses. For streptococcal pharyngitis in patients over 1 year of age and for skin and skin structure infections, the total daily dose may be divided and administered every 12 hours. In severe infections, the dosage may be doubled. In the therapy of otitis media, clinical studies have shown that a dosage of 75 to 100 mg/kg/day in 4 divided doses is required. In the treatment of β-hemolytic streptococcal infections, a therapeutic dosage of Keflex should be administered for at least 10 days.
Route of Administration: Oral
In Vitro Use Guide
All strains of group A beta-hemolytic streptococci and Diplococcus pneumoniae were inhibited by 3.1 mug/ml. Of the Staphylococcus aureus strains, 88% were inhibited by 6.3 mug/ml, and 12.5 mug/ml was inhibitory for all S. aureus, 80% of Escherichia coli, 72% of Klebsiella-Aerobacter, and 56% of Proteus mirabilis strains. About 90 to 96% of E. coli, Klebsiella Aerobacter, and P. mirabilis strains were inhibited by 25 mug of cephalexin per ml. Pseudomonas and indole-positive Proteus strains proved to be quite resistant to cephalexin.
Substance Class Chemical
Created
by admin
on Fri Dec 15 15:18:57 GMT 2023
Edited
by admin
on Fri Dec 15 15:18:57 GMT 2023
Record UNII
OBN7UDS42Y
Record Status Validated (UNII)
Record Version
  • Download
Name Type Language
CEPHALEXIN
ORANGE BOOK   USAN   USP   USP-RS   VANDF  
USAN  
Official Name English
CEFALEXIN MONOHYDRATE
EP   WHO-DD  
Common Name English
66873
Code English
7-(D-.ALPHA.-AMINO-.ALPHA.-PHENYLACETAMIDO)-3-METHYL-3-CEPHEM-4-CARBOXYLIC ACID MONOHYDRATE
Common Name English
KEFLEX
Brand Name English
CEPHALEXIN MONOHYDRATE [MI]
Common Name English
CEFANEX
Brand Name English
CEPHALEXIN MONOHYDRATE
MI   VANDF  
Common Name English
CEPHALEXIN [USP-RS]
Common Name English
(6R,7R)-7-[(R)-2-Amino-2-phenylacetamido]-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid monohydrate
Systematic Name English
CEPHALEXIN [USAN]
Common Name English
CEFALEXIN MONOHYDRATE [EP IMPURITY]
Common Name English
CEPHALEXIN [VANDF]
Common Name English
NovoLexin
Brand Name English
Cefalexin monohydrate [WHO-DD]
Common Name English
CEFALEXIN MONOHYDRATE [EP MONOGRAPH]
Common Name English
Biocef
Brand Name English
CEPHALEXIN MONOHYDRATE [VANDF]
Common Name English
KEFLET
Brand Name English
CEPHALEXIN [USP MONOGRAPH]
Common Name English
CEPHALEXIN [ORANGE BOOK]
Common Name English
PANIXINE DISPERDOSE
Brand Name English
LY-66873
Code English
Classification Tree Code System Code
LIVERTOX NBK548358
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
NCI_THESAURUS C357
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
NDF-RT N0000175488
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
LIVERTOX NBK548666
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
CFR 21 CFR 520.376
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
Code System Code Type Description
IUPHAR
4832
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
SMS_ID
100000092402
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
DAILYMED
OBN7UDS42Y
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
ChEMBL
CHEMBL1727
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PRIMARY
MESH
D002506
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PRIMARY
CAS
23325-78-2
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PRIMARY
RXCUI
215948
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
PUBCHEM
62921
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PRIMARY
EVMPD
SUB06165MIG
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
RXCUI
2231
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
ALTERNATIVE
MERCK INDEX
m3244
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY Merck Index
NCI_THESAURUS
C356
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PRIMARY
FDA UNII
OBN7UDS42Y
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
EPA CompTox
DTXSID30945995
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
LACTMED
Cephalexin
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
DRUG BANK
DBSALT001841
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
CHEBI
3535
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
RS_ITEM_NUM
1099008
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PRIMARY
EVMPD
SUB01098MIG
Created by admin on Fri Dec 15 15:18:57 GMT 2023 , Edited by admin on Fri Dec 15 15:18:57 GMT 2023
PRIMARY
Related Record Type Details
BINDER->LIGAND
BINDING
BASIS OF STRENGTH->SUBSTANCE
ASSAY (HPLC)
USP
TRANSPORTER -> SUBSTRATE
PARENT -> SALT/SOLVATE
ANHYDROUS->SOLVATE
TRANSPORTER -> INHIBITOR
Related Record Type Details
ACTIVE MOIETY
Name Property Type Amount Referenced Substance Defining Parameters References
Volume of Distribution PHARMACOKINETIC
Biological Half-life PHARMACOKINETIC RENAL IMPAIRMENT
PHARMACOKINETIC
Tmax PHARMACOKINETIC
MIC BIOLOGICAL PATHOGEN: METHICILLIN-RESISTANT STAPHYLOCOCCI, MOST STRAINS OF ENTEROCOCCI, MOST STRAINS OF ENTEROBACTER spp., MORGANELLA MORGANII, AND PROTEUS VULGARIS

SUSCEPTIBILITY: RESISTANT

Biological Half-life PHARMACOKINETIC
Volume of Distribution PHARMACOKINETIC
MIC BIOLOGICAL PATHOGEN: S. AUREUS (INCLUDING PENILILLINASE-PRODUCING STRAINS), S. PNEUMONIAE, S. PYOGENES, E. COLI, H. INFLUENZAE, K. PNEUMONIAE, M. CATARRHALIS, P. MIRABILIS

SUSCEPTIBILITY: SUSCEPTIBLE