SABA — Bronchodilator Pregnancy: Use with caution — safe for acute asthma treatment; SC tocolysis use restricted per MHRA 2011 warning

Terbutaline

Brand names: Bricanyl

Adult dose

Dose: 2.5–5 mg nebulised (acute); 500 mcg inhaler (2 puffs) PRN

Route: Nebulised / Inhaler (Turbohaler)

Frequency: PRN (inhaler); every 4–6 hours (nebulised in acute setting); SC 250–500 mcg (severe acute asthma)

Max: 5 mg per nebulisation; SC 500 mcg per dose

Alternative SABA to salbutamol. Available as Turbohaler DPI — preferred by some patients with poor MDI technique. SC route (Bricanyl SC) used in severe/near-fatal asthma when inhaled route inadequate. IV infusion used in some centres for acute severe asthma refractory to nebulised treatment.

Paediatric dose

Dose: 2.5–5 mg nebulised (>5 years); 2.5 mg for 2–5 years mg/kg

Route: Nebulised

Frequency: Every 20–30 minutes initially in acute asthma; PRN maintenance

Max: 5 mg per nebulisation

BNFc: acute severe asthma — terbutaline 5 mg nebulised (children ≥5 years); 2.5 mg (1 month–4 years). Equivalent to salbutamol nebulisation.

Dose adjustments

Renal

No dose adjustment required

Hepatic

No dose adjustment required

Paediatric weight-based calculator

Patient weight (kg)

BNFc: acute severe asthma — terbutaline 5 mg nebulised (children ≥5 years); 2.5 mg (1 month–4 years). Equivalent to salbutamol nebulisation.

Clinical pearls

MHRA 2011: terbutaline SC injection (Bricanyl) restricted for tocolysis to short-term hospital use only due to risk of serious maternal cardiac side effects (pulmonary oedema, cardiac arrest)
Turbohaler DPI: breath-actuated — good for patients with coordination difficulties using MDI; no spacer needed
Hypokalaemia monitoring essential in acute severe asthma: high-dose nebulised beta-2 agonists + IV aminophylline + systemic steroids all lower potassium
SC terbutaline 500 mcg for life-threatening asthma when IV access unavailable — bridge to nebulised treatment; adrenaline IM is alternative in anaphylaxis-associated bronchoconstriction
Equivalent bronchodilator efficacy to salbutamol — choice based on patient preference and inhaler device familiarity

Contraindications

Hypersensitivity to terbutaline
Tocolysis (MHRA 2011 — terbutaline SC tocolysis restricted to short-term use in hospital only)

Side effects

Tremor
Tachycardia
Palpitations
Hypokalaemia (high doses)
Headache
Peripheral vasodilation

Interactions

Beta-blockers — antagonise bronchodilator effect (avoid non-selective beta-blockers in asthma)
Theophylline — additive hypokalaemia risk
Corticosteroids, diuretics — additive hypokalaemia

Monitoring

Peak flow / spirometry (response to bronchodilation)
Serum K⁺ (high-dose use)
Heart rate and rhythm

Reference: BNFc; BNF 90; BNFc; MHRA Drug Safety Update (2011) Terbutaline tocolysis; BTS/SIGN Asthma Guidelines 2019; NICE NG80. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways