Name

Terbutaline (Brethine®)

Class

Sympathomimetic

Bronchodilator

Description/Mechanism

Terbutaline is selective for beta 2 adrenergic receptors, resulting in relaxation of smooth muscles of the bronchial tree and peripheral vasculature. It is effective in producing immediate bronchodilation with minimal cardiac effects.

Onset

SQ: 15-30 minutes

MDI: 5-30 minutes

Duration

SQ: 1.5-4 hr

MDI: 3-6 hr

Indications

Bronchospasm associated with asthma, exercise, chronic bronchitis or emphysema

Contraindications

Hypersensitivity

Tachydysrhythmias

Digitalis-induced tachycardia

Adverse Reactions

Usually transient and dose-related

Restlessness, apprehension

Palpitations

Tachycardia

Chest pain

Coughing

Bronchospasm

Nausea

Facial flushing

Drug Interactions

Other sympathomimetics may exacerbate adverse cardiovascular effects. MAO inhibitors may potentiate tachydysrhythmias.

Beta blockers may antagonize terbutaline

Supplied

Parenteral: 1mg/ml ampules

MDI: 200 mcg/metered spray

Dose/Administration

Adult

Parenteral: 0.25 mg SQ, may repeat in 15-30 minutes (max dose 0.5 mg/4 hr).

MDI: 2 inhalations (400 mcg) every 4-6 hours; allow 1-2 minutes between inhalations.

Solution: 0.15-1.0 mg/dose in 2 ml NS by nebulizer

Pediatric

Parenteral: 0.01 mg/kg/dose SQ every 15-20 minutes prn, (max dose 0.25 mg)

MDI: Same as for adults

Solution: 0.03 – 0.05 mg/kg in 2 ml NS by nebulizer

Special Consideration

Pregnancy Safety: Category B

Not FDA approved in children less than 12 years of ages

Carefully monitor vital signs

Use with caution in patients with cardiovascular disease or hypertension.

NOTE: All bronchodilators may initially worsen hypoxemia by increasing ventilation-perfusion mismatching. Therefore, these patients should receive oxygen prior to and during bronchodilator administration.