Cephalexin

RECENT MAJOR CHANGES Indications and Usage ( 1 ) 3/2026 Dosage and Administration ( 2 ) 3/2026

1 INDICATIONS AND USAGE Cephalexin USP 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 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.

2 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 ( 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 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 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 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 recommended. In severe infections, a total daily dose of 50 to 100 mg/kg may be administered in equally divided doses. For the treatment of otitis media, the recommended daily dose is 75 to 100 mg/kg given in equally divided doses. See Table 1 for the dosage of Cephalexin 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 Direction for Mixing cephalexin for oral susapension 125 mg/5 mL (100 mL when mixed): Prepare suspension time at dispensing. Add to the bottle a total of 69 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 138 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 69 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 138 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). After mixing, the different concentrations and volumes of the suspension as describ …

3 DOSAGE FORMS AND STRENGTHS For oral suspension 125 mg/5mL and 250 mg/5mL of cephalexin as pink coloured powder for reconstitution in a multidose bottle that forms a pink coloured suspension with characteristic odour on constitution for each strength, respectively. For oral suspension: 125 mg/5mL and 250 mg/5mL of cephalexin as a powder in a multi-dose bottle for reconstitution ( 3 )

4 CONTRAINDICATIONS Cephalexin is contraindicated in patients with known hypersensitivity to cephalexin or other members of the cephalosporin class of antibacterial drugs. Patients with known h ypersensitivity to cephalexin or other m e mbers of the cephalosporin class of antibacterial drugs. (4)

6 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 [ seeWarnings 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 for oral suspension include diarrhea, nausea, vomiting, dyspepsia and abdominal pain. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Lupin Pharmaceuticals, Inc. at 1-800-399-2561 or to 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.

7 DRUG INTERACTIONS • Metformin: increased metformin concentrations. Monitor for hypoglycemia. ( 7.1 ) • Probenecid-The renal excretion of cephalexin for oral suspension is inhibited by probenecid. Co-administration of probenecid with cephalexin for oral suspension is not recommended. ( 7.2 ) • Administration of cephalexin for oral suspension 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.

8 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 of cephalexin use in pregnant women have not established drug-associated risks of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Available studies have methodologic limitations, including small sample size, retrospective data collection, and inconsistent comparator groups. 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 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 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 report that cephalexin is present in human milk. The relative infant dose (RID) is considered to be <l% of the maternal weight adjusted dose. There are limited data on the effects of cephalexin on the breastfed child. There are no data on the effects of cephalexin on milk production. The developmental 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 have been established in pediatric patients aged one year and older in clinical trials [see Indications and Usage ( 1.1 – 1.5 )] for the dosages described in the dosage and administration section [see Dosage and Administration ( 2.1 , 2.2) ]. The safety and effectiveness of cephalexin have not been established in pediatric patients younger than one year old. 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 Administration ( 2.3 ) ]. Monitor patients longer for toxicity and drug interactions due to delayed clearance.

12.1 Mechanism of Action Cephalexin is a cephalosporin antibacterial drug [ see Microbiology ( 12.4 ) ].

11 DESCRIPTION Cephalexin for oral suspension, USP is a semisynthetic cephalosporin antibacterial drug intended for oral administration. It is 7- (D-α-Amino-α-phenylacetamido)-3-methyl-3-cephem-4-carboxylic acid monohydrate. Cephalexin has the molecular formula C 16 H 17 N 3 O 4 S • H 2 O and the molecular weight is 365.41. Cephalexin has the following structural formula: Cephalexin for oral suspension, USP is supplied in a multi-dose bottle as pink coloured powder containing 125 mg/5 mL or 250 mg/5 mL of cephalexin for oral use following reconstitution with water. Freshly reconstituted solutions of cephalexin yield a pink coloured suspension with characteristic odour on constitution for the 125 mg/5 mL and 250 mg/5 mL strengths, respectively. The inactive ingredients in the cephalexin for oral suspension are colloidal silicon dioxide, FD&C Red No. 40, sodium benzoate, strawberry flavor, sucrose, xanthan gum. Image 01

10 OVERDOSAGE Symptoms of oral overdose may include nausea, vomiting, epigastric distress, diarrhea, and hematuria. In the event of an overdose, institute general supportive measures. Forced diuresis, peritoneal dialysis, hemodialysis, or charcoal hemoperfusion have not been established as beneficial for an overdose of cephalexin.

16 HOW SUPPLIED/STORAGE AND HANDLING Cephalexin for Oral Suspension USP is a Pink coloured powder forming pink coloured suspension with characteristic odour on constitution for the 125mg/5mL and 250mg/5mL strength, respectively, supplied as follows: The 125 mg per 5 mL for oral suspension is available as follows: 100-mL Bottles NDC 68180-440-01 200-mL Bottles NDC 68180-440-02 The 250 mg per 5 mL for oral suspension is available as follows: 100-mL Bottles NDC 68180-441-01 200-mL Bottles NDC 68180-441-02 Directions for mixing are included elsewhere in the labeling [see Dosage and Administration ( 2.3 )] . Prior to mixing, store at 20°C to 25°C (68°F 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 [see Dosage and Administration ( 2.3 )] .