Schedule H

Oral

• Tablets: 250 mg, 500 mg

• Capsules: 250 mg, 500 mg

• Oral Suspension: 125 mg/5 mL, 250 mg/5 mL

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

⮞ Uncomplicated Urinary Tract Infections (Cystitis)

Parameter Recommendation

Starting dose 500 mg orally every 12 hours

Titration Not applicable

Usual maintenance dose 500 mg every 12 hours

Maximum dose 4 g/day

Key Clinical Notes:

• Duration: 5–7 days for uncomplicated cystitis

• Not suitable for complicated UTI or pyelonephritis

• Covers E. coli, Klebsiella, Proteus (non-ESBL strains)

• Obtain culture if no response within 48–72 hours

⮞ Skin and Soft Tissue Infections (SSTI)

(Cellulitis, impetigo, wound infections, furuncles — MSSA or Streptococcus spp.)

Parameter Recommendation

Starting dose 500 mg orally every 8 hours

Titration Increase to 500 mg every 6 hours for moderate-severe infections

Usual maintenance dose 500 mg every 6–8 hours

Maximum dose 4 g/day

Key Clinical Notes:

• Duration: 7–10 days depending on clinical response

• Effective against Staphylococcus aureus (MSSA) and Streptococcus pyogenes

• Not effective against MRSA

• Review if no improvement within 48–72 hours

⮞ Pharyngitis / Tonsillitis (Streptococcus pyogenes)

Parameter Recommendation

Starting dose 500 mg orally every 12 hours

Titration Not applicable

Usual maintenance dose 500 mg every 12 hours

Maximum dose 2 g/day

Key Clinical Notes:

• Duration: 10 days mandatory (rheumatic fever prevention)

• Alternative to penicillin in patients with non-anaphylactic penicillin allergy

• Complete full course even if symptoms resolve early

⮞ Acute Otitis Media (Non-severe)

Parameter Recommendation

Starting dose 500 mg orally every 6 hours

Titration Not applicable

Usual maintenance dose 500 mg every 6 hours

Maximum dose 4 g/day

Key Clinical Notes:

• Duration: 7–10 days

• Reserve for cases where first-line agents contraindicated

• Covers common middle ear pathogens (S. pneumoniae, H. influenzae non-beta-lactamase producing)

⮞ Respiratory Tract Infections (Non-severe Bronchitis)

Parameter Recommendation

Starting dose 500 mg orally every 8 hours

Titration Increase to 500 mg every 6 hours if needed

Usual maintenance dose 500 mg every 6–8 hours

Maximum dose 4 g/day

Key Clinical Notes:

• Duration: 7 days

• Not first-line for community-acquired pneumonia

• Consider for acute exacerbation of chronic bronchitis with suspected Gram-positive aetiology

Secondary Indications — Adults (Off-label, if any)

Indication Dose Duration Notes

Dental infections (abscess, post-extraction) 500 mg every 6–8 hours 3–5 days OFF-LABEL; Based on Indian dental practice and institutional protocols

Surgical prophylaxis (oral step-down post-discharge) 500 mg every 6 hours 24–48 hours post-operatively OFF-LABEL; Specialist only; Based on Indian surgical practice

PAEDIATRIC DOSING (Specialist Only)

Primary Indications

⮞ Pharyngitis / Tonsillitis / Upper Respiratory Tract Infections

Weight-based Dosing:

Parameter Recommendation

Starting dose 25 mg/kg/day in 2 divided doses

Titration Increase to 50 mg/kg/day for moderate infections

Usual maintenance dose 25–50 mg/kg/day divided every 12 hours

Maximum dose 1 g/day or adult dose

Key Clinical Notes:

• Duration: 10 days for streptococcal pharyngitis

• Minimum age: >1 month

⮞ Skin and Soft Tissue Infections (Paediatric)

Parameter Recommendation

Starting dose 50 mg/kg/day in 3–4 divided doses

Titration Increase to 100 mg/kg/day for severe infections

Usual maintenance dose 50–100 mg/kg/day divided every 6–8 hours

Maximum dose 4 g/day or adult dose

Key Clinical Notes:

• Duration: 7–10 days

• Minimum age: >1 month

⮞ Uncomplicated Urinary Tract Infections (Paediatric)

Parameter Recommendation

Starting dose 50 mg/kg/day in divided doses

Titration Increase to 100 mg/kg/day for moderate infections

Usual maintenance dose 50–100 mg/kg/day divided every 6–8 hours

Maximum dose 4 g/day or adult dose

Key Clinical Notes:

• Duration: 7–10 days

• Obtain urine culture before initiating therapy

• Minimum age: >1 month

Safety Monitoring:

• Monitor for GI disturbances (diarrhoea, nausea, vomiting)

• Watch for signs of hypersensitivity (rash, urticaria)

• Monitor for oral thrush with prolonged use

Secondary Indications — Paediatrics (Off-label, if any)

Indication Dose Duration Notes

Dental abscess 25–50 mg/kg/day in divided doses 3–5 days OFF-LABEL; Specialist only; Based on Indian paediatric dental practice

Age Restriction Statement:

Not recommended in neonates below 1 month of age except under infectious disease specialist supervision due to immature renal function.

50 No adjustment required

10–50 Give usual dose every 8–12 hours

<10 Extend dosing interval to every 12–24 hours

Haemodialysis Administer dose after dialysis; supplemental dose may be required

Peritoneal dialysis Extend interval to every 12–24 hours

Note: Monitor closely for neurotoxicity (confusion, seizures) in severe renal impairment.

• Known hypersensitivity to cefalexin or any cephalosporin antibiotic

• History of severe immediate-type hypersensitivity (anaphylaxis) to penicillins or other beta-lactam antibiotics

• Known hypersensitivity to any excipient in the formulation

• History of non-severe penicillin allergy — cross-reactivity possible (approximately 1–2%); may use with caution after risk assessment

• Renal impairment — dose adjustment required to prevent accumulation

• History of gastrointestinal disease, particularly antibiotic-associated colitis

• Prolonged use — risk of superinfection with resistant organisms or C. difficile

• False-positive urinary glucose tests with Benedict's solution or Fehling's solution (use glucose oxidase methods)

• Not effective against MRSA, ESBL-producing organisms, or Pseudomonas aeruginosa

• History of seizures — risk may be increased with accumulation in renal dysfunction

Parameter Information

Risk category Generally considered safe (Category B equivalent)

Safety statement No evidence of teratogenicity; crosses placenta but extensive clinical experience supports safety

Preferred use Commonly used in Indian obstetric practice for UTI and SSTI

Preferred alternatives Amoxicillin-clavulanate (if penicillin-sensitive); Cefadroxil (equally safe alternative)

When to use When indicated for susceptible infections

Monitoring Monitor clinical response; renal function if treating complicated UTI

Parameter Information

Compatibility Compatible with breastfeeding

Drug level in milk Low (small amounts excreted)

Preferred alternatives None required; cefalexin is acceptable

Infant monitoring Watch for diarrhoea, oral thrush, or skin rash

• Starting dose: Same as adult dose (500 mg every 8–12 hours)

• Titration: Adjust based on renal function assessment

• Additional considerations:

• Assess baseline renal function before initiation (age-related decline common)

• Adjust dose according to calculated CrCl even if serum creatinine appears normal

• Higher susceptibility to renal-related drug accumulation

• Monitor for signs of C. difficile-associated diarrhoea

• Maintain adequate hydration during therapy

• Increased risk of confusion with accumulation in renal impairment

Interacting Drug Effect Management

Probenecid Increases cefalexin serum levels by inhibiting renal tubular secretion; prolonged half-life Avoid combination unless clinically justified; if used, monitor for toxicity

Metformin Increased risk of lactic acidosis if renal function compromised due to competition for renal excretion Monitor renal function and blood glucose closely

Interacting Drug Effect Management

Warfarin Potentiation of anticoagulant effect reported rarely Monitor INR closely, especially with prolonged antibiotic use

Live typhoid vaccine (Ty21a) May reduce vaccine immunogenicity Avoid concurrent administration; complete antibiotic course 3 days before vaccination

Loop diuretics (furosemide) May potentiate nephrotoxicity Monitor renal function; ensure adequate hydration

Aminoglycosides Additive nephrotoxicity when used together Monitor renal function closely; avoid prolonged combination

• Diarrhoea

• Nausea

• Vomiting

• Abdominal pain/discomfort

• Skin rash

• Urticaria

• Headache

• Dyspepsia

• Mild eosinophilia

• Oral candidiasis (with prolonged use)

Adverse Effect Clinical Notes

Anaphylaxis / Angioedema Immediate hypersensitivity; discontinue immediately; emergency care required

Stevens-Johnson Syndrome / TEN Rare; discontinue immediately and refer for hospitalisation

Pseudomembranous colitis (C. difficile) Suspect with severe or persistent diarrhoea; discontinue and treat appropriately

Acute interstitial nephritis Rare; presents with fever, rash, eosinophilia, renal impairment

Hepatocellular injury Rare; monitor LFTs if symptomatic

Haemolytic anaemia Rare; Coombs-positive haemolytic anaemia reported

Seizures Rare; associated with accumulation in renal impairment

Phase Parameters

Baseline Renal function (especially in elderly or pre-existing renal disease); allergy history (cephalosporin/penicillin)

During therapy Clinical assessment for GI symptoms, signs of hypersensitivity, diarrhoea

Prolonged therapy (>10 days) Renal function; LFTs; CBC

Long-term/repeated courses Periodic renal function; monitor for superinfection

• Sporidex (Ranbaxy/Sun Pharma)

• Keflex (Eli Lilly)

• Cepodem (Glenmark)

• Lexin (Alkem)

• Zolexin (Zydus)

• Phexin (GSK)

• Alcephin (Alembic)

• Multiple generic preparations available

Note: Not included in NLEM; not NPPA price-controlled; generally affordable; widely available across India.

1. Acid-stable and food-flexible: Cefalexin is acid-stable and can be taken with or without food; food may reduce GI upset but does not significantly affect absorption.

1. Safe in non-anaphylactic penicillin allergy: Cross-reactivity with penicillins is low (approximately 1–2%); safe to use in patients with history of mild, non-anaphylactic penicillin allergy.

1. Interchangeable with cefadroxil: Near-interchangeable with cefadroxil for most indications; cefalexin requires more frequent dosing (TID-QID) compared to cefadroxil (BID).

1. Achieves adequate urinary concentrations: Useful option for uncomplicated cystitis; primarily renally excreted with good urinary drug levels.

1. No MRSA/ESBL/Pseudomonas coverage: First-generation cephalosporin with no activity against MRSA, ESBL-producing Enterobacteriaceae, or Pseudomonas — do not use empirically for suspected resistant infections.

1. Good step-down option: Well-tolerated oral antibiotic; suitable for step-down therapy following IV first-generation cephalosporins (e.g., cefazolin).

Cefalexin; Cephalexin; cephalosporin; first-generation cephalosporin; antibiotic; UTI; cystitis; skin infection; SSTI; pharyngitis; beta-lactam; renal-adjustment; pregnancy-safe; breastfeeding-compatible; paediatric-appropriate; Schedule H

RxIndia v1.0 — 10 Jan 2025

• CDSCO Approved Formulations List

• Indian Pharmacopoeia / National Formulary of India (NFI) 2021

• API Textbook of Medicine

• AIIMS Antimicrobial Policy 2023

• ICMR AMR Treatment Guidelines

• IAP Paediatric Dosing Guidelines

• Harrison's Principles of Internal Medicine

• Goodman & Gilman's: The Pharmacological Basis of Therapeutics