Cephalexin

Use only for proven or strongly suspected susceptible bacterial infections; use cultures and local susceptibility patterns when selecting or revising treatment. This is not treatment for a viral cold. MRSA, most enterococci, Pseudomonas and several other gram-negative organisms are resistant or outside activity. The current suspension indications include adults and children age ≥1; younger infants require a separate assessment.

The table below follows the current suspension label. The capsule table lists the same lower-clearance regimens but prints “>60” rather than “≥60”; verify the exact capsule prescription at that boundary. These tables do not establish a renal regimen for younger children or hemodialysis.

May be given with or without meals. Use an oral measuring device and confirm suspension concentration: 125 mg/5 mL = 25 mg/mL; 250 mg/5 mL = 50 mg/mL. Shake well. Have the pharmacist prepare the exact bottle and verify the prescribed mL/dose from weight and concentration; reconstitution water amounts vary between products. Do not use the selected suspension label’s inconsistent 40 kg/125 mg-per-5 mL twice-daily volume example as a dosing rule. Its age ≥1 indication and “over 1 year” dosage heading also require confirmation for a child exactly age 1. The labeled 7–14 days is not a blanket duration for every infection or a substitute for current local treatment guidance.

Known hypersensitivity to cephalexin or another cephalosporin antibacterial. A penicillin-allergy history requires assessment of the reaction and beta-lactam cross-hypersensitivity; it is not silently rewritten as an absolute label contraindication.

The selected capsule and oral-suspension labels have no boxed warning. Their allergy, antibiotic-associated colitis, renal and seizure risks still require attention.

Diarrhea is the most frequent trial reaction; nausea, vomiting, dyspepsia and abdominal pain also occur. Reported serious reactions include allergy/severe skin reactions, hemolytic anemia or other blood-cell changes, interstitial nephritis and transient hepatitis/cholestatic jaundice. Overdose may cause gastrointestinal distress or blood in the urine; obtain Poison Help/medical advice for supportive care. Forced diuresis or dialysis has not been established as beneficial for overdose.

• Cephalexin can increase metformin concentrations and reduce its renal clearance; monitor carefully and adjust metformin when indicated. Multiple-dose interaction data are limited.
• Probenecid inhibits renal excretion of cephalexin; coadministration is not recommended.
• Benedict/Fehling urine glucose tests may be falsely positive; inform the laboratory. Direct Coombs positivity can also complicate blood testing.
• Anticoagulant therapy is a risk factor for prolonged prothrombin time during cephalosporin treatment; monitor at-risk patients rather than assuming a routine fixed adjustment.

Decades of observational cephalosporin data have not established an association with major birth defects, miscarriage or other adverse pregnancy outcomes, but the studies have limitations. Use for an assessed bacterial indication. Cephalexin is present in human milk at a reported relative infant dose <1%; infant-effect information is limited and milk-production data are absent. Weigh breastfeeding benefits and maternal need.

Current suspension labeling establishes use from age 1 and not below 1; its dosage heading says over age 1, so confirm dosing at the exact age boundary. The renal-adjustment table is for adults/age ≥15. A suitable suspension allows small weight-based doses without assuming a child can take a fixed capsule. Older adults need renal-based selection; studies showed no overall age-related difference in response.

Use lower or less frequent regimens according to the age-appropriate renal guidance and monitor patients with impairment for accumulation, toxicity and interactions. Hemodialysis dosing and younger-child renal algorithms are not established by these tables. The reviewed labels supply no numeric hepatic-dose adjustment; hepatic impairment does increase the need to consider prothrombin-time monitoring.

A bactericidal cephalosporin that inhibits bacterial cell-wall synthesis. The labeled staphylococcal activity is against methicillin-susceptible isolates; do not infer MRSA, enterococcal or Pseudomonas coverage.

Absorption / meals

Acid stable; may be taken without regard to meals. Peak concentrations measured around 1 hour.

Protein binding

Approximately 10–15%.

Elimination

Glomerular filtration and tubular secretion; over 90% excreted unchanged in urine within 8 hours in studied conditions.

Clinical implication

Reduced renal clearance prolongs exposure; use the applicable renal regimen.

Review allergy history, kidney function, infection site and culture/susceptibility evidence. Assess response and superinfection during therapy. Monitor renal function closely with severe impairment; check prothrombin time when risk factors warrant and investigate new anemia/hemolysis. Severe diarrhea or a new rash/swelling requires assessment rather than routine continuation.

Use the exact prescribed dose and duration; do not share or save antibiotics for a viral illness. Obtain immediate help for breathing trouble, facial/throat swelling or a severe rash. Report watery/bloody diarrhea during or after treatment. For liquid, verify the concentration and measured mL, shake well, refrigerate after mixing and discard after 14 days. A pharmacist should resolve the selected label’s inconsistent pediatric volume row; household teaspoons are unsuitable for precise measurement.

Ingredient / route

Cephalexin monohydrate equivalent to 500 mg cephalexin · oral.

Appearance / imprint

Dark green / light green hard gelatin capsule; A 43 / 500 mg.

Manufacturer / distributor

Aurobindo Pharma Limited / Aurobindo Pharma USA.

Example NDC

65862-019-01 · bottle of 100.

U.S. status

Prescription antibacterial; no pharmacy stock claim.

Selected capsules

250 mg (A 42 / 250 mg); 500 mg (A 43 / 500 mg).

Selected oral suspensions

125 mg/5 mL and 250 mg/5 mL after constitution; bottles producing 100 or 200 mL.

Suspension package examples

125 mg/5 mL: 59651-322-01/-02; 250 mg/5 mL: 59651-323-01/-02.

Scope

Other capsule/tablet strengths, brands and compounded formulations require their exact labels; no injectable cephalexin regimen is supplied.

Capsules: 20–25°C, excursions 15–30°C; dispense in a tight light-resistant container. Selected suspension powder: 20–25°C, tightly closed. After exact-product reconstitution, refrigerate and keep for no more than 14 days; shake well before every measured dose. Manufacturer water-addition volumes cannot be exchanged between bottles.