Terbutaline Pediatric Dose — Asthma & Respiratory
Terbutaline is a selective beta-2 adrenergic agonist that causes bronchial smooth muscle relaxation through stimulation of beta-2 receptors, reducing airway resistance. It is used intravenously in pediatric patients with severe or refractory bronchospasm, including status asthmaticus, when inhaled therapy is insufficient. IV terbutaline is typically reserved for PICU settings where continuous cardiorespiratory monitoring is available.
Pediatric Dosing
- Loading dose: 10 mcg/kg slow IV bolus administered over 10 minutes.
- Continuous infusion (starting dose): 0.2 mcg/kg/min IV.
- Titration: May increase by 0.1 mcg/kg/min every 30 minutes as needed.
- Maximum infusion rate: 2 mcg/kg/min IV.
Worked example for a 20 kg child:
- Loading dose: 20 × 10 mcg/kg = 200 mcg IV over 10 minutes.
- Starting infusion: 20 × 0.2 mcg/kg/min = 4 mcg/min.
- Each titration step: 20 × 0.1 mcg/kg/min = 2 mcg/min increase every 30 minutes.
- Maximum infusion: 20 × 2 mcg/kg/min = 40 mcg/min.
Indications and Clinical Context
IV terbutaline is indicated for severe, refractory bronchospasm in pediatric patients with status asthmaticus who have not responded adequately to inhaled bronchodilators, systemic corticosteroids, and other first-line therapies. It is classified as a rescue or escalation therapy in the PICU setting and is consistent with advanced management algorithms for refractory pediatric asthma. Its use should be considered in the context of institutional protocols and in coordination with PICU or pulmonology specialists.
The systemic beta-2 agonist effect provides bronchodilation when inhaled drug delivery is limited by severe airflow obstruction, making IV administration a rational escalation strategy in critically ill pediatric patients.
Administration and Monitoring
Terbutaline should be administered intravenously via a dedicated IV line in a monitored PICU setting. The loading dose must be given slowly over 10 minutes to minimize cardiovascular adverse effects. The continuous infusion should be delivered via a calibrated infusion pump. Titrate in increments of 0.1 mcg/kg/min no more frequently than every 30 minutes, up to a maximum of 2 mcg/kg/min; consult institutional protocol for preparation and concentration standards.
- Monitoring: Continuous cardiac monitoring, pulse oximetry, and frequent blood pressure assessment are essential.
- Adverse effects: Tachycardia, hypokalemia, hyperglycemia, tremor, and lactic acidosis may occur; monitor electrolytes and lactate.
- Caution: Use with care in patients with pre-existing tachyarrhythmias or hypertension; reassess risk-benefit continuously during infusion.
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.