Salbutamol

Listed in Dosage.

Adult: PO Acute bronchospasm 2-4 mg 3 or 4 times/day, up to 8 mg 3 or 4 times/day. As modified-release tab: 8 mg bid. IV Severe bronchospasm As 50 mcg/mL soln: 250 mcg (4 mcg/kg) injected slowly. May be repeated if necessary. As 10 mcg/mL soln: Usual rate of 3-20 mcg/min (0.3-2 mL/min). Higher doses may be used in resp failure. Uncomplicated premature labour at 22-37 wk of gestation Initial: 10 mcg/min, increasing gradually at 10-min intervals until there is response, then increase rate slowly until contractions cease. Maintain rate for 1 hr after contractions have stopped, then gradually reduce rate by 50% at intervals of 6 hr. Usual: 10-45 mcg/min. Max duration: 48 hr. IM/SC Severe bronchospasm 500 mcg (8 mcg/kg) and repeated 4 hrly as required. Inhalation Acute bronchospasm As metered-dose aerosol or dry powd inhaler: 1 or 2 inhalations up to 4 times/day. Max: 800 mcg/day. Prophylaxis of exercise-induced bronchospasm As metered-dose aerosol or dry powd inhaler: 2 inhalations 10-15 min prior to exercise. Severe bronchospasm Via nebuliser: 2.5-5 mg, up to 4 times/day or, continuously at a rate of 1-2 mg/hr. Acute severe asthma As metered-dose inhaler via spacer device: Initial: 4 inhalations, then a further 2 inhalations every 2 min according to response. Max: 10 inhalations.

IV (in the treatment of premature labour): Pre-existing or risk factors for ischaemic heart disease, gestational age <22 wk, conditions in which prolongation of pregnancy is hazardous (e.g. severe toxaemia, intrauterine infection, vag bleeding resulting from placenta praevia, eclampsia or severe preeclampsia, placental abruption, cord compression; use in threatened abortion.

Hyperthyroidism, myocardial insufficiency, arrhythmias, susceptibility to QT-interval prolongation, HTN, DM, glaucoma, hypokalaemia, seizure disorder. Renal impairment. Elderly. Pregnancy and lactation. Monitoring Parameters Monitor BP, heart rate, electrolyte and fluid balance; glucose, lactate and K levels.

Tremor, nervousness, nausea and vomiting, tachycardia, palpitations, chest pain, shakiness, dizziness, headache, insomnia, inhalation site sensation, hyperactivity, HTN, hypotension, increased sweating, allergic reactions, DM, muscle cramps, flu-like syndrome, conjunctivitis, UTI, hypokalaemia,. Rarely, erythema multiforme, Stevens-Johnson syndrome.
Potentially Fatal: Paradoxical bronchospasm.

Increased risk of hypokalaemia w/ K depleting agents (e.g. corticosteroid, diuretics, xanthines, digoxin). Increased uterine inertia w/ halogenated anaesth (IV). Increased risk of pulmonary oedema w/ corticosteroids. May antagonise the effect of anti-diabetics. Effects may be altered by guanethidine, reserpine, methyldopa, TCAs and MAOIs. Increased risk of CV effects w/ other sympathomimetic agents. Antagonistic effect w/ β-blockers.

Drugs Acting on the Uterus / Antiasthmatic & COPD Preparations

R03AC02 - salbutamol ; Belongs to the class of adrenergic inhalants, selective beta-2-adrenoreceptor agonists. Used in the treatment of obstructive airway diseases.
R03CC02 - salbutamol ; Belongs to the class of adrenergics for systemic use, selective beta-2-adrenoreceptor agonists. Used in the treatment of obstructive airway diseases.