What are the most common medications and their dosages for pediatric patients?

Common Pediatric Medications and Dosages

Antibiotics

Amoxicillin

• For most infections, dose amoxicillin at 20-45 mg/kg/day divided every 8-12 hours in children over 3 months of age 1
• For neonates and infants 3 months or younger, the maximum dose is 30 mg/kg/day divided every 12 hours 1
• For severe infections requiring higher doses, use 45 mg/kg/day at the upper end of the dosing range 2

Amoxicillin-Clavulanate

• Dose at 20-40 mg/kg/day (based on amoxicillin component) divided into 3 doses, with a maximum daily dose of 4000 mg of the amoxicillin component 2

Cephalexin

• For urinary tract infections, dose at 50-100 mg/kg/day divided into 4 doses 2

Ceftriaxone

• For neonates ≤7 days old, dose at 50 mg/kg/day given every 24 hours 2
• For neonates >7 days old and >2000 g, dose at 50-75 mg/kg/day given every 24 hours 2
• Never use ceftriaxone in hyperbilirubinemic neonates due to displacement of bilirubin and kernicterus risk 2

Ampicillin

• For neonates ≤7 days old and ≤2000 g, dose at 50 mg/kg/day divided every 12 hours 2
• For neonates ≤7 days old and >2000 g, dose at 75 mg/kg/day divided every 8 hours 2

Gentamicin

• For neonates 0-4 weeks and <1200 g, dose at 7.5 mg/kg every 18-24 hours 2
• For neonates ≤7 days and >2000 g, dose at 7.5-10 mg/kg every 12 hours 2
• Always adjust doses in renal impairment, as gentamicin is renally eliminated 2

Clindamycin

Intravenous Dosing

• For serious infections including MRSA, dose at 40 mg/kg/day divided every 6-8 hours (10-13 mg/kg/dose every 6-8 hours, not exceeding 40 mg/kg/day total) 3, 4
• For pneumonia, use 10-13 mg/kg/dose every 6-8 hours 3
• For bacteremia in stable children without endovascular infection, use 10-13 mg/kg/dose IV every 6-8 hours 3

Oral Dosing

• For MRSA and methicillin-susceptible Staphylococcus aureus infections, dose at 30-40 mg/kg/day divided into 3-4 doses 3, 4
• For Group A Streptococcus infections, dose at 40 mg/kg/day in 3 doses 3, 4

Practical Example

• For an 8.2 kg child, the total daily dose is 328 mg/day, which can be divided every 8 hours into 109 mg per dose or every 6 hours into 82 mg per dose 4

Critical Caveats

• Do not use clindamycin if local MRSA clindamycin resistance rates are >10% 3
• Never use clindamycin for endocarditis or endovascular infections, as it is inadequate for these conditions 3
• For severe Group A Streptococcus with toxic shock, combine with penicillin due to superior toxin suppression 3

Antituberculosis Medications

Isoniazid

• Dose at 10-15 mg/kg (maximum 300 mg) for children 2

Rifampin

• Dose at 10-20 mg/kg (maximum 600 mg) for children 2

Medications for Acute Agitation/Behavioral Emergencies

Benzodiazepines

Lorazepam

• For acute agitation, dose at 0.05-0.1 mg/kg PO/IM/IV, may repeat every 30-60 min 5
• Onset: 15 min IM, 5-10 min IV 5
• Peak: 1 h IM, 20-30 min PO 5
• Duration: 6-8 h PO/IM 5
• Benzodiazepines are the most commonly used drug for acute pediatric agitation and are preferred for intoxication/withdrawal 5

Midazolam

• Dose at 0.1 mg/kg PO/IM/IV 5
• Onset: 10-15 min IM, 5-15 min IV 5
• Peak: 15-30 min IM, 30 min IV 5
• Duration: 1 h IM, 2 h IV 5

Antipsychotics

Haloperidol (First-Generation)

• Child (6-12 years): 0.25-0.50 mg PO/IM 5
• Adolescent: 0.5-1 mg PO/IM 5
• May repeat IM every 20-30 min, maximum 30 mg daily 5
• Onset: 20-30 min IM, 45-60 min PO 5
• Peak: 10-20 min IM, 30-60 min PO 5
• Duration: 4-8 h 5

Risperidone (Second-Generation)

• Child: 0.5-2 mg PO 5
• Adolescent: 2-5 mg PO 5
• May repeat PO every 60 min, maximum 40 mg daily 5
• Onset: 20-30 min PO 5
• Peak: 60 min 5
• Duration: ≤24 h 5
• Risperidone is the second most commonly used drug in pediatric patients and may cause fewer extrapyramidal symptoms than first-generation drugs 5

Combination Therapy for Severe Agitation

• For older adolescents (>16 years), combine haloperidol with lorazepam or midazolam for additive effect 5
• For younger adolescents (12-16 years), use risperidone with lorazepam or midazolam 5

Clinical Decision Algorithm for Agitation

• For suspected medical/intoxication etiology: Use benzodiazepine first, consider adding first-generation antipsychotic for severe cases 5
• For psychiatric etiology with mild/moderate agitation: Use benzodiazepine or antipsychotic 5
• For psychiatric etiology with severe agitation: Use antipsychotic 5
• For unknown etiology: Give a dose of benzodiazepine or antipsychotic; consider a dose of the other medication if the first dose is not effective 5

Critical Monitoring

• Monitor for respiratory depression, hypotension, and paradoxical behavioral disinhibition from benzodiazepines, especially in younger children and those with developmental disabilities 5
• Monitor for dystonic reactions, orthostatic hypotension, sinus tachycardia, and other dysrhythmias with antipsychotics 5

Antihypertensive Medications

ACE Inhibitors

Benazepril

• Initial dose: 0.2 mg/kg/day up to 10 mg/day 5
• Maximum dose: 0.6 mg/kg/day up to 40 mg/day 5
• Dosing interval: Once daily 5

Captopril

• Initial dose: 0.3-0.5 mg/kg/dose (for children >12 months) 5
• Maximum dose: 6 mg/kg/day 5
• Dosing interval: Three times daily 5

Lisinopril

• Initial dose: 0.07 mg/kg/day up to 5 mg/day 5
• Maximum dose: 0.6 mg/kg/day up to 40 mg/day 5
• Dosing interval: Once daily 5

Critical Caveats for ACE Inhibitors

• All ACE inhibitors are contraindicated in pregnancy; women of childbearing age should use reliable contraception 5
• Check serum potassium and creatinine periodically to monitor for hyperkalemia and azotemia 5

Angiotensin Receptor Blockers (ARBs)

Losartan

• Initial dose: 0.7 mg/kg/day up to 50 mg/day 5
• Maximum dose: 1.4 mg/kg/day up to 100 mg/day 5
• Dosing interval: Once to twice daily 5

Critical Caveats for ARBs

• All ARBs are contraindicated in pregnancy; women of childbearing age should use reliable contraception 5
• Check serum potassium and creatinine levels periodically to monitor for hyperkalemia and azotemia 5

Beta-Blockers

Labetalol (Combined Alpha and Beta-Antagonist)

• Initial dose: 1-3 mg/kg/day 5
• Maximum dose: 10-12 mg/kg/day up to 1200 mg/day 5
• Dosing interval: Twice daily 5
• Asthma and overt heart failure are relative contraindications 5

Atenolol

• Initial dose: 0.5-1 mg/kg/day 5
• Maximum dose: 2 mg/kg/day up to 100 mg/day 5
• Dosing interval: Once to twice daily 5

Critical Principles for Pediatric Dosing

• Children are not dosed as small adults, and simple weight-based scaling from adult doses is inappropriate 2
• Always adjust doses in renal impairment, particularly for renally eliminated drugs like aminoglycosides and beta-lactams 2
• For severe infections, use the higher end of the dosing range 2
• Evaluate a patient's age, size, and level of organ maturity when selecting doses 6