Please check your internet connection and try again.
# Bricanyl (Terbutaline)
## Overview
Terbutaline is a selective beta-2 adrenergic agonist. It acts as a bronchodilator by stimulating adenyl cyclase to increase cyclic AMP levels, causing smooth muscle relaxation in the bronchial tree. It also possesses tocolytic properties (uterine relaxation).
## Primary Indications
* **Respiratory:** Reversible airway obstruction (asthma, COPD).
* **Obstetrics:** Management of preterm labor (off-label; use restricted due to maternal/fetal safety concerns).
## Adult Dosing
* **Subcutaneous (Asthma):** 0.25 mg injected into the lateral deltoid area. May repeat once after 15–30 minutes if necessary. Do not exceed 0.5 mg in a 4-hour period.
* **Oral (Asthma):** 2.5–5 mg every 6 hours; maximum 15 mg/day.
* **Inhalation:** 2 inhalations (0.4–0.5 mg) every 4–6 hours.
## Pediatric Dosing
* **Subcutaneous:** 0.005–0.01 mg/kg/dose (max 0.25 mg) every 15–20 minutes for up to 3 doses.
* **Oral (12+ years):** 2.5 mg every 6–8 hours.
* **Oral (Children 6–12 years):** 2.5 mg every 8 hours.
## Dose Adjustments
* **Renal Impairment:** Reduce dosage in patients with significant renal impairment; terbutaline is excreted primarily by the kidneys.
* **Hepatic Impairment:** No specific guidelines; use caution and monitor for increased sympathetic effects.
## Contraindications
* Known hypersensitivity to sympathomimetic amines.
* Use as a tocolytic beyond 48-72 hours (FDA Boxed Warning: Risk of maternal heart problems and death).
* Cardiac arrhythmias associated with tachycardia.
## Adverse Effects
* **Common:** Tremor (especially in hands), nervousness, palpitations, tachycardia, dizziness, and headache.
* **Serious:** Hypokalemia (at high doses), cardiac arrhythmias, myocardial ischemia, hyperglycemia, and pulmonary edema (specifically in tocolysis).
## Key Drug Interactions
* **Beta-Blockers:** Antagonize the effect of terbutaline and may trigger bronchospasm.
* **Diuretics (Loop/Thiazide):** May potentiate ECG changes or hypokalemia induced by beta-agonists.
* **MAO Inhibitors/TCAs:** May potentiate the effects on the vascular system.
## Monitoring
* **Cardiac:** Pulse, blood pressure, and ECG (if high dose/IV).
* **Respiratory:** FEV1 or peak flow, respiratory rate, and oxygen saturation.
* **Labs:** Serum potassium and glucose levels (especially in diabetic or high-risk patients).
## Clinical Pearls
* **Tolerance:** Prolonged use of SABA inhalers may lead to receptor downregulation.
* **Tocolysis Warning:** Due to the risk of maternal myocardial ischemia and pulmonary edema, the FDA advises against the use of oral or long-term (>48 hours) injectable terbutaline for preterm labor.
* **Administration:** Ensure patients with asthma receive proper instruction on inhaler technique.
***
*Disclaimer: This information is for educational purposes only. Dosing protocols may vary by institution and local guidelines. Always verify current prescribing information, patient-specific contraindications, and drug-drug interactions via an official reference like Lexicomp or the manufacturer’s package insert before prescribing or administering medication.*
