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Cephalexin
Overview
Active ingredients
Source: NDC DirectoryForms, strengths and routes
Source: NDC DirectoryPharmacologic classes are listed in the class section below.
Pharmacologic class
Source: NDC Directory| Class | Type | Browse |
|---|---|---|
| Cephalosporin Antibacterial [EPC] | EPC | All 41 members |
| Cephalosporins [CS] | CS | All 41 members |
Regulatory status
Source: Drugs@FDANDC Directory| Product | Trade name | Form | Strength | Ingredient | Status | TE | Flags |
|---|---|---|---|---|---|---|---|
| 062703-001 | CEPHALEXIN | FOR SUSPENSION | CEPHALEXIN | Prescription | AB | ||
| 062703-002 | CEPHALEXIN | FOR SUSPENSION | CEPHALEXIN | Prescription | AB | RS |
Therapeutic equivalence
Source: Orange BookWhat this rating means: Therapeutically equivalent — bioequivalence demonstrated by in vivo or in vitro testing
Codes beginning with “A” indicate products the FDA considers therapeutically equivalent. Codes beginning with “B” indicate bioequivalence has not been established. See methodology.
Approval history
Source: Drugs@FDA| Type | No. | Action | Status | Date | Review |
|---|---|---|---|---|---|
| Supplement | 54 | Labeling | Approved | August 21, 2012 | Standard |
| Supplement | 52 | Labeling | Approved | February 22, 2011 | — |
| Supplement | 51 | Labeling | Approved | November 16, 2009 | — |
| Supplement | 49 | Labeling | Approved | September 27, 2007 | — |
| Supplement | 47 | Labeling | Approved | February 9, 2007 | — |
| Supplement | 40 | Labeling | Approved | January 13, 2004 | — |
| Supplement | 39 | Labeling | Approved | January 13, 2004 | — |
| Supplement | 35 | Manufacturing (CMC) | Approved | August 1, 2002 | — |
| Supplement | 34 | Manufacturing (CMC) | Approved | June 18, 2002 | — |
| Supplement | 32 | Manufacturing (CMC) | Approved | February 20, 2002 | — |
| Supplement | 33 | Manufacturing (CMC) | Approved | August 14, 2001 | — |
| Supplement | 31 | Manufacturing (CMC) | Approved | July 7, 2000 | — |
| Supplement | 30 | Manufacturing (CMC) | Approved | January 18, 2000 | — |
| Supplement | 29 | Manufacturing (CMC) | Approved | July 21, 1998 | — |
| Supplement | 28 | Manufacturing (CMC) | Approved | August 19, 1997 | — |
| Supplement | 27 | Manufacturing (CMC) | Approved | October 4, 1996 | — |
| Supplement | 26 | Manufacturing (CMC) | Approved | May 10, 1996 | — |
| Supplement | 25 | Manufacturing (CMC) | Approved | November 27, 1995 | — |
| Supplement | 23 | Manufacturing (CMC) | Approved | July 17, 1995 | — |
| Supplement | 24 | Manufacturing (CMC) | Approved | February 16, 1995 | — |
| Supplement | 22 | Manufacturing (CMC) | Approved | September 6, 1994 | — |
| Supplement | 21 | Labeling | Approved | October 13, 1993 | — |
| Supplement | 20 | Manufacturing (CMC) | Approved | October 27, 1988 | — |
| Supplement | 18 | Manufacturing (CMC) | Approved | September 30, 1988 | — |
| Supplement | 19 | Manufacturing (CMC) | Approved | September 14, 1988 | — |
| Supplement | 16 | Manufacturing (CMC) | Approved | August 25, 1988 | — |
| Supplement | 17 | Manufacturing (CMC) | Approved | August 4, 1988 | — |
| Supplement | 15 | Manufacturing (CMC) | Approved | May 31, 1988 | — |
| Original application | 1 | Approved | February 13, 1987 | — |
Prescribing information
Source: openFDA Drug LabelingReproduced verbatim from the Structured Product Labeling submitted to the FDA (effective 20260721). This is the manufacturer's labelling text, not a summary and not advice.
Recent Major Changes
openFDA Drug LabelingIndications and Usage ( 1 ) 3/2026 Dosage and Administration ( 2 ) 3/2026
Indications and Usage
openFDA Drug Labeling1 INDICATIONS AND USAGE Cephalexin for oral suspension is a cephalosporin antibacterial drug indicated for the treatment of the following infections caused by susceptible isolates of designated bacteria in adults and pediatric patients aged one year and older: Respiratory tract infection ( 1.1 ) Otitis media ( 1.2 ) Skin and skin structure infections ( 1.3 ) Bone infections ( 1.4 ) Genitourinary tract infections ( 1.5 ) To reduce the development of drug-resistant bacteria and maintain the effectiveness of cephalexin for oral suspension and other antibacterial drugs, cephalexin for oral suspension should be used only to treat infections that are proven or strongly suspected to be caused by bacteria. ( 1.6 ) 1.1 Respiratory Tract Infections Cephalexin for oral suspension is indicated for the treatment of respiratory tract infections caused by susceptible isolates of Streptococcus pneumoniae and Streptococcus pyogenes in adults and pediatric patients aged one year and older. 1.2 Otitis Media Cephalexin for oral suspension is indicated for the treatment of otitis media caused by susceptible isolates of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Moraxella catarrhalis in adults and pediatric patients aged one year and older. 1.3 Skin and Skin Structure Infections Cephalexin for oral suspension is indicated for the treatment of skin and skin structure infections caused by susceptible isolates of the following Gram-positive bacteria: Staphylococcus aureus and Streptococcus pyogenes in adults and pediatric patients aged one year and older. 1.4 Bone Infections Cephalexin for oral suspension is indicated for the treatment of bone infections caused by susceptible isolates of Staphylococcus aureus and Proteus mirabilis in adults and pediatric patients aged one year and older. 1.5 Genitourinary Tract Infections Cephalexin for oral suspension is indicated for the treatment of genitourinary tract infections, including acute prostatitis, caused by susceptible isolates of Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae in adults and pediatric patients aged one year and older. 1.6 Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of cephalexin for oral suspension and other antibacterial drugs, cephalexin for oral suspension should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information is available, this information 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.
Dosage and Administration
openFDA Drug Labeling2 DOSAGE AND ADMINISTRATION Adults and patients at least 15 years of age The usual dose is 250 mg every 6 hours, but a dose of 500 mg every 12 hours may be administered ( 2.1 ). Pediatric patients (over 1 year of age) Otitis media: 75 to 100 mg/kg in equally divided doses every 6 hours ( 2.2 ) All other indications: 25 to 50 mg/kg given in equally divided doses ( 2.2 ) In severe infections: 50 to 100 mg/kg may be administered in equally divided doses ( 2.2 ) Duration of therapy ranges from 7 to 14 days depending on the infection type and severity. ( 2 ) See full prescribing information directions for mixing cephalexin for oral suspension for oral suspension ( 2.3 ) Dosage adjustment is required in patients with severe and end stage renal disease (ESRD) defined as creatinine clearance below 30 mL/min. ( 2.4 ) 2.1 Recommended Dosage for Adults and Pediatric Patients at Least 15 Years of Age The recommended dosage of oral cephalexin for oral suspension is 250 mg every 6 hours, but a dose of 500 mg every 12 hours may be administered. Treatment is administered for 7 to 14 days. For more severe infections larger doses of oral cephalexin for oral suspension may be needed, up to 4 grams daily in two to four equally divided doses. 2.2 Recommended Dosage for Pediatric Patients (over 1 year of age) The recommended total daily dose of oral cephalexin for oral su spens ion for pediatric patients is 25 to 50 mg/kg given in equally divided doses for 7 to 14 days. In the treatment of β-hemolytic streptococcal infections, duration of at least 10 days is recom men ded. In severe infections, a total daily dose of 50 to 100 mg/kg may be adm inister ed in equally divided doses. For the treatment of otitis media, the reco mmen ded daily dose is 75 to 100 mg/kg given in equally divided doses. See Table 1 for the dosage of cep hale xin for oral suspension by weight for pediatric patients. Table 1: Dosage by Weight of Cephalexin for Oral Suspension for Pediatric Patients *teaspoon =tsp Weight of Pediatric Patient Cephalexin for Oral Suspension (125 mg/5mL) Cephalexin for Oral Suspension (250 mg/5mL) OPTION 1 Dosage Dosage 10 kg 1⁄2 to 1 tsp* four times a day 1⁄4 to 1⁄2 tsp four times a day 20 kg 1 to 2 tsp four times a day 1⁄2 to 1 tsp four times a day 40 kg 2 to 4 tsp four times a day 1 to 2 tsp four times a day OPTION 2 10 kg 1 to 2 tsp two times a day 1⁄2 to 1 tsp two times a day 20 kg 2 to 4 tsp two times a day 1 to 2 tsp two times a day 40 kg 2 to 4 tsp two times a day 2 to 4 tsp two times a day 2.3 Directions for Mixing Cephalexin for Oral Suspension 125 mg/5 mL (100 mL when mixed): Prepare suspension time at dispensing. Add to the bottle a total of 67 mL of water. For ease in preparation, tap bottle to loosen powder, add the water in 2 portions, shaking well after each addition. The resulting suspension will contain cephalexin monohydrate equivalent to 125 mg cephalexin in each 5 mL (teaspoonful). 125 mg/5 mL (200 mL when mixed): Prepare suspension time at dispensing. Add to the bottle a total of 134 mL of water. For ease in preparation, tap bottle to loosen powder, add the water in 2 portions, shaking well after each addition. The resulting suspension will contain cephalexin monohydrate equivalent to 125 mg cephalexin in each 5 mL (teaspoonful). 250 mg/5 mL (100 mL when mixed): Prepare suspension time at dispensing. Add to the bottle a total of 67 mL of water. For ease in preparation, tap bottle to loosen powder, add the water in 2 portions, shaking well after each addition. The resulting suspension will contain cephalexin monohydrate equivalent to 250 mg cephalexin in each 5 mL (teaspoonful). 250 mg/5 mL (200 mL when mixed): Prepare suspension time at dispensing. Add to the bottle a total of 134 mL of water. For ease in preparation, tap bottle to loosen powder, add the water in 2 portions, shaking well after each addition. The resulting suspension will contain cephalexin monohydrate equivalent to 250 mg cephalexin in each 5 mL (teaspoonful). …
Dosage Forms and Strengths
openFDA Drug Labeling3 DOSAGE FORMS AND STRENGTHS Cephalexin capsules USP 250 mg: Swedish orange body and gray cap imprinted “TEVA” on the cap and “3145” on the body 500 mg: Swedish orange body and Swedish orange cap imprinted “TEVA” on the cap and “3147” on the body Cephalexin for oral suspension USP A cherry mixed fruit flavored formula - 125 mg/5 mL and 250 mg/5 mL Cephalexin tablets USP 250 mg: Tablet identification number and color: white, capsule-shaped tablet, debossed “2238” on one side with a score between the “2” and the “3” and “TEVA” on the reverse side. 500 mg: Tablet identification number and color: white, capsule-shaped tablet, debossed “2240” on one side with a score between the “2” and the “4” and “TEVA” on the reverse side. Capsules: 250 mg and 500 mg ( 3 ) For oral suspension: 125 mg/5 mL and 250 mg/5 mL Tablets: 250 mg and 500 mg
Contraindications
openFDA Drug Labeling4 CONTRAINDICATIONS Cephalexin for oral suspension is contraindicated in patients with known hypersensitivity to cephalexin or other members of the cephalosporin class of antibacterial drugs. Patients with known hypersensitivity to cephalexin or other members of the cephalosporin class of antibacterial drugs. ( 4 )
Warnings and Cautions
openFDA Drug Labeling5 WARNINGS AND PRECAUTIONS Serious hypersensitivity (anaphylactic) reactions: Prior to use, inquire regarding history of hypersensitivity to beta-lactam antibacterial drugs. Discontinue the drug if signs or symptoms of an allergic reaction occur and institute supportive measures. ( 5.1 ) Clostridioides difficile -Associated Diarrhea (CDAD) : Evaluate if diarrhea occurs. ( 5.2 ) Direct Coombs’ Test Seroconversion: If anemia develops during or after cephalexin therapy, evaluate for drug-induced hemolytic anemia. ( 5.3 ) Seizure Potential: Use lower dose in patients with renal impairment. ( 5.4 ) 5.1 Hypersensitivity Reactions Allergic reactions in the form of rash, urticaria, angioedema, anaphylaxis, erythema multiforme, Stevens-Johnson syndrome, or toxic epidermal necrolysis have been reported with the use of cephalexin. Before therapy with cephalexin is instituted, inquire whether the patient has a history of hypersensitivity reactions to cephalexin, cephalosporins, penicillins, or other drugs. Cross-hypersensitivity among beta-lactam antibacterial drugs may occur in up to 10% of patients with a history of penicillin allergy. If an allergic reaction to cephalexin occurs, discontinue the drug and institute appropriate treatment. 5.2 Clostridioides difficile -Associated Diarrhea Clostridioides difficile -associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including cephalexin, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B, which contribute to the development of CDAD. Hypertoxin-producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated. 5.3 Direct Coombs’ Test Seroconversion Positive direct Coombs’ tests have been reported during treatment with the cephalosporin antibacterial drugs including cephalexin. Acute intravascular hemolysis induced by cephalexin therapy has been reported. If anemia develops during or after cephalexin therapy, perform a diagnostic work-up for drug-induced hemolytic anemia, discontinue cephalexin and institute appropriate therapy. 5.4 Seizure Potential Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment when the dosage was not reduced. If seizures occur, discontinue cephalexin. Anticonvulsant therapy can be given if clinically indicated. 5.5 Prolonged Prothrombin Time Cephalosporins may be associated with prolonged prothrombin time. Those at risk include patients with renal or hepatic impairment, or poor nutritional state, as well as patients receiving a protracted course of antibacterial therapy, and patients receiving anticoagulant therapy. Monitor prothrombin time in patients at risk and manage as indicated. 5.6 Development of Drug-Resistant Bacteria Prescribing cephalexin in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria. Prolonged use of cephalexin may result in the overgrowth of nonsusceptible organisms. Careful observation of the patient is essential. If superinfection occurs during therapy, appropriate measures should be taken.
Warnings
openFDA Drug LabelingWARNINGS BEFORE THERAPY WITH CEPHALEXIN IS INSTITUTED, CAREFUL INQUIRY SHOULD BE MADE TO DETERMINE WHETHER THE PATIENT HAS HAD PREVIOUS HYPERSENSITIVITY REACTIONS TO CEPHALEXIN, CEPHALOSPORINS, PENICILLINS, OR OTHER DRUGS. IF THIS PRODUCT IS TO BE GIVEN TO PENICILLIN-SENSITIVE PATIENTS, CAUTION SHOULD BE EXERCISED BECAUSE CROSS-HYPERSENSITIVITY AMONG BETA-LACTAM ANTIBIOTICS HAS BEEN CLEARLY DOCUMENTED AND MAY OCCUR IN UP TO 10% OF PATIENTS WITH A HISTORY OF PENICILLIN ALLERGY. IF AN ALLERGIC REACTION TO CEPHALEXIN OCCURS, DISCONTINUE THE DRUG. SERIOUS ACUTE HYPERSENSITIVITY REACTIONS MAY REQUIRE TREATMENT WITH EPINEPHRINE AND OTHER EMERGENCY MEASURES, INCLUDING OXYGEN, INTRAVENOUS FLUIDS, INTRAVENOUS ANTIHISTAMINES, CORTICOSTEROIDS, PRESSOR AMINES AND AIRWAY MANAGEMENT, AS CLINICALLY INDICATED. There is some clinical and laboratory evidence of partial cross-allergenicity of the penicillins and the cephalosporins. Patients have been reported to have had severe reactions (including anaphylaxis) to both drugs. Any patient who has demonstrated some form of allergy, particularly to drugs, should receive antibiotics cautiously. No exception should be made with regard to cephalexin. Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including cephalexin, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.
Adverse Reactions
openFDA Drug Labeling6 ADVERSE REACTIONS The following serious events are described in greater detail in the Warning and Precautions section: Hypersensitivity reactions [ see Warning and Precautions ( 5.1 ) ] Clostridium difficile -associated diarrhea [ see Warnings and Precautions ( 5.2 ) ] Direct Coombs’ Test Seroconversion [ see Warnings and Precautions ( 5.3 ) ] Seizure Potential [ see Warnings and Precautions ( 5.4 ) ] Effect on Prothrombin Activity [ see Warnings and Precautions ( 5.5 ) ] Development of Drug-Resistant Bacteria [ see Warnings and Precautions ( 5.6 ) ] The most common adverse reactions associated with cephalexin include diarrhea, nausea, vomiting, dyspepsia and abdominal pain. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact TEVA USA, PHARMACOVIGILANCE at 1-866-832-8537 or drug.safety@tevapharm.com or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In clinical trials, the most frequent adverse reaction was diarrhea. Nausea and vomiting, dyspepsia, gastritis, and abdominal pain have also occurred. As with penicillins and other cephalosporins, transient hepatitis and cholestatic jaundice have been reported. Other reactions have included hypersensitivity reactions, genital and anal pruritus, genital candidiasis, vaginitis and vaginal discharge, dizziness, fatigue, headache, agitation, confusion, hallucinations, arthralgia, arthritis, and joint disorder. Reversible interstitial nephritis has been reported. Eosinophilia, neutropenia, thrombocytopenia, hemolytic anemia, and slight elevations in aspartate transaminase (AST) and alanine transaminase (ALT) have been reported. In addition to the adverse reactions listed above that have been observed in patients treated with cephalexin, the following adverse reactions and other altered laboratory tests have been reported for cephalosporin class antibacterial drugs: Other Adverse Reactions : Fever, colitis, aplastic anemia, hemorrhage, renal dysfunction, and toxic nephropathy. Altered Laboratory Tests: Prolonged prothrombin time, increased blood urea nitrogen (BUN), increased creatinine, elevated alkaline phosphatase, elevated bilirubin, elevated lactate dehydrogenase (LDH), pancytopenia, leukopenia, and agranulocytosis.
Drug Interactions
openFDA Drug Labeling7 DRUG INTERACTIONS Metformin: increased metformin concentrations. Monitor for hypoglycemia. ( 7.1 ) Probenecid - The renal excretion of cephalexin is inhibited by probenecid. Co-administration of probenecid with cephalexin is not recommended. ( 7.2 ) Administration of cephalexin may result in a false-positive reaction for glucose in the urine. ( 7.3 ) 7.1 Metformin Administration of cephalexin with metformin results in increased plasma metformin concentrations and decreased renal clearance of metformin. Careful patient monitoring and dose adjustment of metformin is recommended in patients concomitantly taking cephalexin and metformin [ see Clinical Pharmacology ( 12.3 ) ]. 7.2 Probenecid The renal excretion of cephalexin is inhibited by probenecid. Co-administration of probenecid with cephalexin is not recommended. 7.3 Interaction with Laboratory or Diagnostic Testing A false-positive reaction may occur when testing for the presence of glucose in the urine using Benedict’s solution or Fehling’s solution.
Use in Specific Populations
openFDA Drug Labeling8 USE IN SPECIFIC POPULATIONS Renal Impairment: Monitor patients longer for toxicity and drug interactions due to delayed clearance. ( 8.6 ) 8.1 Pregnancy Risk Summary Available data from published epidemiologic studies and pharmacovigilance case reports over several decades with cephalosporin use, including Cephalexin use in pregnant women have not established drug-associated risks of major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data) . Animal reproduction studies with mice and rats using oral doses of cephalexin that are 0.6- and 1.2-times the maximum recommended human dose (MRHD) based on body surface area during organogenesis revealed no evidence of harm to the fetus (see Data). The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data While available studies cannot definitively establish the absence of risk, published data from epidemiologic studies and postmarketing case reports over several decades have not identified a consistent association with cephalosporin use, including Cephalexin, during pregnancy, and major birth defects, miscarriage, or other adverse maternal or fetal outcomes. Available studies have methodologic limitations, including small sample size, retrospective data collection, and inconsistent comparator groups. Animal Data In animal reproduction studies, pregnant mice and rats administered oral cephalexin doses of 250 or 500 mg/kg/day (approximately 0.6 and 1.2 times the MRHD) based on body surface area, respectively during the period of organogenesis showed no adverse effects on embryofetal development. In a pre-and post-natal developmental toxicity study, pregnant rats that received oral doses of 250 or 500 mg/kg/day of cephalexin from Day 15 of pregnancy to litter Day 21 showed no adverse effects on parturition, litter size, or growth of offspring. 8.2 Lactation Risk Summary Data from a published clinical lactation study reports that cephalexin is present in human milk. The Relative Infant Dose (RID) is considered to be <1% of the maternal weight adjusted dose. There are no data on the effects of cephalexin on the breastfed child or on milk production. The development of health benefits of breastfeeding should be considered along with the mother’s clinical need for cephalexin and any potential adverse effects on the breastfed child from cephalexin or from the underlying maternal condition. 8.4 Pediatric Use The safety and effectiveness of cephalexin in pediatric patients was established in clinical trials for the dosages described in the dosage and administration section [ see Dosage and Administration ( 2.2 ) ] . 8.5 Geriatric Use Of the 701 subjects in 3 published clinical studies of cephalexin, 433 (62%) were 65 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients. This drug is substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection [ see Warnings and Precautions ( 5.4 ) ]. 8.6 Renal Impairment Cephalexin should be administered with careful monitoring in the presence of renal impairment (creatinine clearance < 30 mL/min, with or without dialysis). Under such conditions, careful clinical observation and laboratory studies renal function monitoring should be conducted because safe dosage may be lower than that usually recommended [see Dosage and Administra …
Mechanism of Action
openFDA Drug Labeling12.1 Mechanism of Action Cephalexin is a cephalosporin antibacterial drug [see Microbiology ( 12.4 )] .
Description
openFDA Drug Labeling11 DESCRIPTION Cephalexin, USP is a semisynthetic cephalosporin antibiotic intended for oral administration. It is 7-(D-α-amino-α-phenylacetamido)-3-methyl-3-cephem-4-carboxylic acid, monohydrate. Cephalexin, USP has the following structural formula: C 16 H 17 N 3 O 4 S•H 2 O M.W. 365.41 The nucleus of cephalexin, USP is related to that of other cephalosporin antibiotics. The compound is a zwitterion; i.e., the molecule contains both a basic and an acidic group. The isoelectric point of cephalexin, USP in water is approximately 4.5 to 5. The crystalline form of cephalexin, USP which is available is a monohydrate. It is a white crystalline solid having a bitter taste. Solubility in water is low at room temperature; 1 or 2 mg/mL may be dissolved readily, but higher concentrations are obtained with increasing difficulty. The cephalosporins differ from penicillins in the structure of the bicyclic ring system. Cephalexin, USP has a D -phenylglycyl group as substituent at the 7-amino position and an unsubstituted methyl group at the 3-position. Each capsule contains cephalexin monohydrate, USP equivalent to 250 mg (720 μmol) or 500 mg (1,439 μmol) of cephalexin. Inactive Ingredients: CAPSULES: magnesium stearate, silicon dioxide, and sodium starch glycolate. Capsule Shell and Print Constituents: black iron oxide, D&C Yellow #10 Aluminum Lake, FD&C Blue #1 Aluminum Lake, FD&C Blue #2 Aluminum Lake, FD&C Red #40 Aluminum Lake, gelatin, pharmaceutical glaze modified in SD-45, silicon dioxide or carboxymethylcellulose sodium, sodium lauryl sulfate, titanium dioxide and may contain propylene glycol. In addition, the 250 mg capsule shell contains yellow iron oxide. After mixing, each 5 mL of cephalexin for oral suspension USP will contain cephalexin monohydrate, USP equivalent to 125 mg (360 μmol) or 250 mg (720 μmol) of cephalexin. Inactive Ingredients: SUSPENSION: FD&C Red #40, cherry mixed fruit flavor (artificial flavors, benzyl alcohol, maltodextrin, and modified corn starch), silicon dioxide, sodium benzoate, sugar (fruit granulated), and xanthan gum. Each tablet contains cephalexin monohydrate, USP equivalent to 250 mg (720 μmol) or 500 mg (1,439 μmol) of cephalexin. Inactive Ingredients: TABLETS: hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, sodium starch glycolate, and titanium dioxide. structure
Overdosage
openFDA Drug LabelingOVERDOSAGE Signs and Symptoms Symptoms of oral overdose may include nausea, vomiting, epigastric distress, diarrhea, and hematuria. If other symptoms are present, it is probably secondary to an underlying disease state, an allergic reaction, or toxicity due to ingestion of a second medication. Treatment To obtain up-to-date information about the treatment of overdose, a good resource is your certified Regional Poison Control Center. Telephone numbers of certified poison control centers are listed in the Physicians’ Desk Reference ( PDR ). In managing overdosage, consider the possibility of multiple drug overdoses, interaction among drugs, and unusual drug kinetics in your patient. Unless 5 to 10 times the normal dose of cephalexin has been ingested, gastrointestinal decontamination should not be necessary. Protect the patient’s airway and support ventilation and perfusion. Meticulously monitor and maintain, within acceptable limits, the patient’s vital signs, blood gases, serum electrolytes, etc. Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage; consider charcoal instead of or in addition to gastric emptying. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient’s airway when employing gastric emptying or charcoal. Forced diuresis, peritoneal dialysis, hemodialysis, or charcoal hemoperfusion have not been established as beneficial for an overdose of cephalexin; however, it would be extremely unlikely that one of these procedures would be indicated. The oral median lethal dose of cephalexin in rats is > 5000 mg/kg.
How Supplied / Storage and Handling
openFDA Drug Labeling16 HOW SUPPLIED/STORAGE AND HANDLING Cephalexin Capsules USP 250 mg: Swedish orange body and gray cap imprinted “TEVA” on the cap and “3145” on the body, in bottles of 100 (NDC 0093-3145-01) and 500 (NDC 0093-3145-05). 500 mg: Swedish orange body and Swedish orange cap imprinted “TEVA” on the cap and “3147” on the body, in bottles of 100 (NDC 0093-3147-01) and 500 (NDC 0093-3147-05). Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Dispense in a tight, light-resistant container. Cephalexin for Oral Suspension * USP (a cherry mixed fruit flavored formula) 125 mg/5 mL: bottles of 100 mL (NDC 0093-4175-73) and 200 mL (NDC 0093-4175-74). 250 mg/5 mL: bottles of 100 mL (NDC 0093-4177-73) and 200 mL (NDC 0093-4177-74). Directions for mixing are included on the label. Store dry powder at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature]. Shake well before using. Keep tightly closed. * After mixing, store in refrigerator. May be kept for 14 days without significant loss of potency.
Adverse event reports
Source: openFDA FAERSAttributed to this product's most-reported active ingredient: CEPHALEXIN. Combination products with more than six active ingredients are not attributed, because a report count summed across a long ingredient list measures the list, not the medicine.
Packaging and NDCs
Source: NDC Directory| Package NDC | Product NDC | Labeler | Description | Marketing start |
|---|---|---|---|---|
| 59651-322-01 | 59651-322 | Aurobindo Pharma Limited | 100 mL in 1 BOTTLE (59651-322-01) | June 9, 2026 |
| 59651-322-02 | 59651-322 | Aurobindo Pharma Limited | 200 mL in 1 BOTTLE (59651-322-02) | June 9, 2026 |
| 59651-323-01 | 59651-323 | Aurobindo Pharma Limited | 100 mL in 1 BOTTLE (59651-323-01) | June 9, 2026 |
| 59651-323-02 | 59651-323 | Aurobindo Pharma Limited | 200 mL in 1 BOTTLE (59651-323-02) | June 9, 2026 |
| 62135-480-42 | 62135-480 | Chartwell RX, LLC | 100 mL in 1 BOTTLE (62135-480-42) | February 1, 2022 |
| 62135-480-49 | 62135-480 | Chartwell RX, LLC | 200 mL in 1 BOTTLE (62135-480-49) | February 1, 2022 |
| 62135-481-42 | 62135-481 | Chartwell RX, LLC | 100 mL in 1 BOTTLE (62135-481-42) | February 1, 2022 |
| 62135-481-49 | 62135-481 | Chartwell RX, LLC | 200 mL in 1 BOTTLE (62135-481-49) | February 1, 2022 |
| 66267-982-00 | 66267-982 | NuCare Pharmaceuticals,Inc. | 100 mL in 1 BOTTLE (66267-982-00) | July 18, 2017 |
| 63187-205-00 | 63187-205 | Proficient Rx LP | 100 mL in 1 BOTTLE (63187-205-00) | November 3, 2014 |
| 63187-205-20 | 63187-205 | Proficient Rx LP | 200 mL in 1 BOTTLE (63187-205-20) | November 3, 2014 |
| 0093-4175-73 | 0093-4175 | Teva Pharmaceuticals USA, Inc. | 100 mL in 1 BOTTLE (0093-4175-73) | September 30, 1990 |
| 0093-4175-74 | 0093-4175 | Teva Pharmaceuticals USA, Inc. | 200 mL in 1 BOTTLE (0093-4175-74) | September 30, 1990 |
| 0093-4177-73 | 0093-4177 | Teva Pharmaceuticals USA, Inc. | 100 mL in 1 BOTTLE (0093-4177-73) | September 30, 1990 |
| 0093-4177-74 | 0093-4177 | Teva Pharmaceuticals USA, Inc. | 200 mL in 1 BOTTLE (0093-4177-74) | September 30, 1990 |
| 59651-322 | 59651-322 | Aurobindo Pharma Limited | — | June 9, 2026 |
| 59651-323 | 59651-323 | Aurobindo Pharma Limited | — | June 9, 2026 |
| 62135-480 | 62135-480 | Chartwell RX, LLC | — | February 28, 2018 |
| 62135-481 | 62135-481 | Chartwell RX, LLC | — | February 28, 2018 |
| 66267-982 | 66267-982 | NuCare Pharmaceuticals,Inc. | — | September 30, 1990 |
| 63187-205 | 63187-205 | Proficient Rx LP | — | September 30, 1990 |
| 0093-4175 | 0093-4175 | Teva Pharmaceuticals USA, Inc. | — | September 30, 1990 |
| 0093-4177 | 0093-4177 | Teva Pharmaceuticals USA, Inc. | — | September 30, 1990 |
Sources for this page
| Dataset | Agency | Used for |
|---|---|---|
| NDC Directory | FDA | Identity, ingredients, strengths, forms, routes, labelers, packages |
| Drugs@FDA | FDA | Application, sponsor, submissions, review documents, marketing status |
| Orange Book | FDA | Therapeutic equivalence codes, reference drug flags, patents, exclusivity |
| Drug Labeling | FDA / NLM | Prescribing information reproduced above |
| FAERS | FDA | Adverse event report counts |
Generated September 25, 2026 · 12 sections on this page.