What are the appropriate doses for all medications?

Drug Dosing Guidelines

The appropriate doses for medications vary significantly by drug class, indication, patient age, weight, and organ function, and must be selected based on specific clinical context rather than a universal approach. Below is a structured framework for key medication categories with evidence-based dosing recommendations.

Antimicrobial Agents

Penicillins

• Amoxicillin dosing in adults ranges from 750-1750 mg/day divided every 8-12 hours 1
• For pediatric patients over 3 months: 20-45 mg/kg/day divided every 8-12 hours 1
• Neonates and infants ≤3 months: maximum 30 mg/kg/day divided every 12 hours 1
• For H. pylori eradication in adults: 1 gram twice daily with clarithromycin 500 mg and lansoprazole 30 mg for 14 days (triple therapy), or 1 gram three times daily with lansoprazole 30 mg for 14 days (dual therapy) 1
• Dose reduction required when GFR <30 mL/min 1

Cephalosporins

• Cefazolin for staphylococcal infections in pediatrics: 150 mg/kg/day divided every 8 hours 2
• For infective endocarditis: 100 mg/kg/day IV divided every 8 hours (maximum 12 g daily) in both pediatric and adult patients 2, 3
• For CNS infections, maintain every 8-hour dosing intervals even at high doses to ensure adequate penetration 2
• Cephalexin for MSSA skin/soft tissue infections: 500 mg orally 4 times daily 3
• Cephalexin lacks adequate coverage for MRSA and Pasteurella multocida 3

Fluoroquinolones

• Levofloxacin for MDR-TB: 750-1000 mg daily in adults; 15-20 mg/kg/day once daily in children; reduce to 3 times weekly with renal impairment 4
• Moxifloxacin for MDR-TB: 400-800 mg daily in adults; 10-15 mg/kg/day once daily in children; no dose adjustment needed for renal impairment 4
• For NTM pulmonary disease: moxifloxacin 400 mg daily; ciprofloxacin 500-750 mg twice daily (adjust to 250-500 mg based on creatinine clearance with renal impairment) 4

Aminoglycosides

• Amikacin for MDR-TB: 15 mg/kg daily (some prefer 25 mg/kg 3 times weekly) in adults; 15-20 mg/kg/day in children 4
• For NTM: 10-15 mg/kg daily or 15-25 mg/kg intermittently, adjusted by therapeutic drug monitoring (target trough <5 mg/L; peak 35-45 μg/mL daily dosing or 65-80 μg/mL intermittent) 4
• Reduce dose or increase interval with renal impairment (e.g., 15 mg/kg 2-3 times weekly) 4
• Streptomycin dosing mirrors amikacin: 10-15 mg/kg daily or 15-25 mg/kg intermittently with similar monitoring and renal adjustments 4

Other Anti-TB/NTM Agents

• Ethambutol: Low dose 15 mg/kg daily as companion drug; high dose 25 mg/kg daily as bacteriostatic agent; increase dosing interval with renal impairment 4
• Linezolid: 600 mg once or twice daily (once daily preferred to reduce toxicity); pediatric dosing varies by weight band (15 mg/kg for 5-9 kg, 12 mg/kg for 10-23 kg, 10 mg/kg >23 kg) 4
• Bedaquiline: 400 mg daily for 14 days, then 200 mg 3 times weekly; for children >12 years and >30 kg use adult dose; 6-12 years and 15-30 kg use half adult dose 4
• Clofazimine: 100-200 mg daily in adults; 2-5 mg/kg/day in children 4

Cardiovascular Medications

Heart Failure with Reduced Ejection Fraction (HFrEF)

Beta-blockers (target doses proven to reduce mortality) 4:

• Bisoprolol: 10 mg once daily (target); 5 mg (50% target)
• Carvedilol: 25 mg twice daily (target 50 mg/day); 12.5 mg twice daily (50% target)
• Metoprolol succinate: 200 mg once daily (target); 100 mg (50% target)
• Initiate at very low doses and titrate every 2 weeks to target or maximally tolerated doses 4

ACE Inhibitors (at least 50% of target dose recommended) 4:

• Enalapril: 10 mg twice daily (target 20 mg/day)
• Lisinopril: 20 mg once daily (target)
• Ramipril: 10 mg once daily (target)

ARBs (when ACE inhibitors not tolerated) 4:

• Candesartan: 32 mg once daily (target)
• Losartan: 100 mg once daily (target, though FDA max is 100 mg)
• Valsartan: 160 mg twice daily (target 320 mg/day)

ARNI 4:

• Sacubitril/valsartan: 97/103 mg twice daily (target 194/206 mg/day)

Atrial Fibrillation

Pharmacological cardioversion 4:

• Flecainide: 200-300 mg single dose (avoid in CAD/structural heart disease; give with beta-blocker or calcium channel blocker 30 minutes prior)
• Propafenone: 450-600 mg single dose (same precautions as flecainide)
• Ibutilide: 1 mg IV over 10 minutes, may repeat once (0.01 mg/kg if <60 kg)
• Dofetilide: dose based on creatinine clearance: 500 mcg twice daily if CrCl >60 mL/min; 250 mcg if 40-60; 125 mcg if 20-40; contraindicated if <20
• Amiodarone: oral loading 600-800 mg daily to 10 g total, then 200 mg daily maintenance; IV 150 mg over 10 minutes, then 1 mg/min for 6 hours, then 0.5 mg/min

Influenza Antivirals

Age-Based Dosing 4

Amantadine (influenza A only):

• Ages 1-9 years: 5 mg/kg/day up to 150 mg in divided doses
• Ages 10-64 years: 100 mg twice daily
• Ages ≥65 years: maximum 100 mg daily (reduced due to declining renal function)
• Adjust for creatinine clearance ≤50 mL/min 4

Rimantadine (influenza A only):

• Ages ≥65 years: 100 mg daily for prophylaxis; 200 mg daily for treatment (reduce to 100 mg if side effects occur)
• Reduce to 100 mg daily with severe hepatic dysfunction or CrCl ≤10 mL/min 4

Zanamivir:

• Ages 7-64 years: 10 mg twice daily via inhalation
• No age-based dose reduction needed 4
• Contraindicated in underlying airway disease due to bronchospasm risk 4

Oseltamivir:

• Weight-based dosing in children; 75 mg twice daily for treatment or once daily for prophylaxis in adults and elderly 4

Critical Dosing Principles

Renal Impairment Adjustments

• Aminoglycosides, fluoroquinolones (ciprofloxacin), clarithromycin, ethambutol, and amoxicillin all require dose reduction or interval extension with declining renal function 4, 1
• Moxifloxacin, linezolid, bedaquiline, and clofazimine require no renal adjustment 4

Therapeutic Drug Monitoring

• Essential for aminoglycosides (amikacin, streptomycin) to prevent ototoxicity and nephrotoxicity while ensuring efficacy 4
• Approximately one-third of patients receiving prolonged aminoglycoside therapy develop permanent ototoxicity; risk increases with age and cumulative dose 4
• Consider lower dose ranges and intermittent dosing for prolonged therapy 4

Pediatric Considerations

• Weight-based dosing (mg/kg) is standard for most antimicrobials in children 4, 1
• Age-specific pharmacokinetic differences require distinct dosing bands for linezolid and other agents 4
• Maximum daily doses often apply regardless of weight to prevent toxicity 2, 3

4, 2, 3, 1