Clindamycin Dosing for Cellulitis in a 30.21 kg Pediatric Patient
For a 30.21 kg child with cellulitis, prescribe oral clindamycin 1,008 mg per day divided into three doses of 336 mg every 8 hours, which equals 6.7 mL of the 75 mg/5 mL suspension per dose.
Weight-Based Dosing Calculation
The Infectious Diseases Society of America recommends clindamycin at 30–40 mg/kg/day divided into 3–4 doses for pediatric skin and soft tissue infections 1.
For moderate cellulitis, target the mid-range of 33.4 mg/kg/day (30.21 kg × 33.4 mg/kg = 1,009 mg/day total) 1, 2.
Divide 1,008 mg/day into three doses of 336 mg every 8 hours (every 8-hour dosing is standard for clindamycin) 1, 2.
Suspension Volume Calculation
The suspension concentration is 75 mg per 5 mL, which equals 15 mg/mL 3.
Each 336 mg dose requires 22.4 mL of suspension (336 mg ÷ 15 mg/mL = 22.4 mL) 3.
Practical rounding: Administer 22.5 mL three times daily (every 8 hours) to achieve approximately 1,012.5 mg/day total 3.
Alternative Four-Times-Daily Dosing
If dividing into four doses every 6 hours, prescribe 252 mg per dose (1,008 mg ÷ 4 = 252 mg) 1, 3.
Each 252 mg dose requires 16.8 mL of suspension (252 mg ÷ 15 mg/mL = 16.8 mL) 3.
Practical rounding: Administer 17 mL four times daily (every 6 hours) to achieve approximately 1,020 mg/day total 3.
Recommended Regimen
Prescribe clindamycin 75 mg/5 mL oral suspension: 22.5 mL three times daily (every 8 hours) for 7–10 days.
Treatment Duration and Monitoring
The Infectious Diseases Society of America recommends 7–10 days of therapy for uncomplicated cellulitis, with 7 days sufficient if clinical improvement occurs within 48–72 hours 1.
Clinical improvement should be evident within 48–72 hours; if no improvement occurs, consider inadequate drainage, deeper infection requiring imaging, or resistant organisms 1.
Inadequate weight-based dosing of clindamycin is independently associated with clinical failure in cellulitis (OR = 2.01, p = 0.032), making proper dosing critical 4.
Important Caveats and Resistance Considerations
Clindamycin should only be used if local MRSA clindamycin resistance rates are <10%, as higher resistance rates compromise efficacy 1.
Perform D-zone testing for erythromycin-resistant MRSA isolates to detect inducible clindamycin resistance before prescribing 1.
If the cellulitis is associated with an abscess, incision and drainage is the cornerstone of treatment; antibiotics provide limited benefit without source control 1.
Administration Instructions
Administer clindamycin with a full glass of water and have the child remain upright for at least 30 minutes to avoid esophageal irritation 3.
Clindamycin may be taken without regard to meals, though administration with food may improve gastrointestinal tolerability 3.
If significant diarrhea occurs during therapy, discontinue clindamycin immediately due to the risk of Clostridioides difficile infection 3.
Indications for Hospitalization
Hospitalization with IV clindamycin (40 mg/kg/day divided every 6–8 hours, maximum 2,400 mg/day) is indicated if systemic signs of toxicity are present (fever >38.5°C, tachycardia, hypotension) or if the cellulitis involves deep structures or difficult anatomic locations 1, 2.
Transition to oral therapy once the patient is afebrile for 24–48 hours and demonstrates clinical improvement 1.