Special Populations>Dose Adjustment Practice Test

A 4-year-old boy (weight 22 kg) presents with fever and sore throat for 1 day. Vitals: T 39.4 C (oral), HR 122, RR 22, BP 98/62, SpO2 99% on room air. He is drinking fluids, vomiting denied. Past history is unremarkable; no asthma, renal disease, or GI bleeding. Allergies: none known. Medications: none at baseline; he received acetaminophen 6 hours ago. Exam shows mild pharyngeal erythema without exudates. The clinician would like to use ibuprofen for antipyresis and analgesia. Renal function is presumed normal for age; last pediatric basic metabolic panel 2 months ago was normal, including serum creatinine 0.3 mg/dL. The family has ibuprofen oral suspension 100 mg/5 mL at home. The pharmacist is asked to recommend an appropriate single dose and frequency for this child, including guidance on interval to avoid excessive dosing.

An 84-year-old woman (weight 58 kg, height 157 cm) with nonvalvular atrial fibrillation presents for anticoagulation management. Vitals: BP 128/72, HR 92 irregularly irregular, T 36.6 C, RR 16. Labs: serum creatinine 1.6 mg/dL, BUN 24 mg/dL, AST/ALT normal. PMH: hypertension, type 2 diabetes, osteopenia. Meds: metformin, lisinopril, vitamin D. Allergies: none. She has no history of stroke or major bleeding. The cardiologist plans to start apixaban. According to apixaban labeling for NVAF, dose reduction to 2.5 mg twice daily is recommended if the patient meets at least 2 of the following: age 80 years or older, body weight 60 kg or less, or serum creatinine 1.5 mg/dL or higher. This patient meets all three criteria (age 84, weight 58 kg, SCr 1.6 mg/dL).