VENTOLIN

What it is

Ventolin contains salbutamol sulfate. The obstetric formulation is a concentrated injection. Ampoules of 5 mL contain salbutamol sulfate equivalent to 5 mg (1 mg/mL) salbutamol BP in a sterile isotonic solution.

Approved indications

— Management of uncomplicated premature labour to arrest labour between 24 and 33 weeks of gestation in patients with no medical or obstetric contraindication to tocolytic therapy.

Dosing overview

Ventolin is for intravenous infusion only and is for obstetric use only, requiring dilution before use. In premature labour, infusion rates of 10–50 micrograms per minute are usually adequate to control uterine contractions. A starting dose of 10 micrograms per minute is recommended, increasing the rate at 10-minute intervals until there is evidence of patient response. The maternal pulse rate should be monitored and the infusion rate adjusted to avoid maternal heart rates in excess of 120 beats per minute. Duration of treatment should not exceed 48 hours as data show that the main effect of tocolytic therapy is a delay in delivery of up to 48 hours.

Key safety warnings

Since salbutamol is a sympathomimetic drug, great care should be used in patients with hypertension or with heart disease, especially in patients with tachyarrhythmias, coronary artery disease, or congestive cardiac failure. In common with other beta-adrenoceptor agonists, Ventolin can induce metabolic changes such as hypokalaemia and increased blood glucose levels. The diabetic patient may be unable to compensate for this and the development of ketoacidosis has been reported. Concurrent administration of corticosteroids can exaggerate this effect. Maternal pulmonary oedema has been reported in association with use of beta-agonists including salbutamol for the management of premature labour; in some cases this has proved fatal. Predisposing factors include fluid overload, multiple pregnancy, pre-existing cardiac disease, maternal infection and pre-eclampsia. Potentially serious hypokalaemia may result from beta-2-agonist therapy mainly from parenteral and nebulised administration. Particular caution is advised in acute severe asthma as this effect may be potentiated by concomitant treatment with xanthine derivatives, steroids, diuretics and hypoxia.

Contraindications

Ventolin is contraindicated in hypersensitivity to any component of the preparation or related sympathomimetic amines. When used in the management of premature labour, Ventolin is contraindicated at a gestational age less than 24 weeks; in the presence of intrauterine foetal death or known lethal congenital or chromosomal malformation; in conditions of the mother or foetus in which prolongation of pregnancy is hazardous (including maternal cardiac disease, uncontrolled hypertension, severe pre-eclampsia, active uterine bleeding, premature rupture of the membranes with associated chorioamnionitis, compression of the umbilical cord, foetal acidosis or hypoxia, and foetal distress); and in patients with pulmonary hypertension, pre-existing ischaemic heart disease or those patients with significant risk factors for ischaemic heart disease. Contraindications also include bronchial asthma, diabetes, uncompensated potassium depletion, hypercalcaemia, maternal hyperthyroidism, ileus, unconsciousness, renal insufficiency, glaucoma and paroxysmal tachycardia.

PBS listing

Ventolin nebuliser solution 2.5 mg in 2.5 mL single dose units (pack of 20) is listed with an ex-manufacturer price of A$4.54. Ventolin nebuliser solution 5 mg in 2.5 mL single dose units (pack of 20) is listed with an ex-manufacturer price of A$4.66. Ventolin oral solution 2 mg per 5 mL (150 mL) is listed with an ex-manufacturer price of A$6.38. Ventolin pressurised inhalation 100 micrograms per dose with dose counter (200 doses) is listed with an ex-manufacturer price of A$8.21.

Regulatory history

Ventolin Obstetric injection (5 mg/5 mL) was first listed on the Australian Register of Therapeutic Goods on 13 August 1991. The first approval date recorded was 31 January 1995. In November 2016, the PBAC recommended a change to pack size and maximum quantity for asthma treatment. In November 2017, the PBAC recommended an amendment to allow salbutamol to be used as a reliever medication for asthma in adult and paediatric patients. In November 2019, the PBAC recommended an unrestricted benefit listing of the pressurised inhalation 100 micrograms formulation with a dose counter for asthma and chronic obstructive pulmonary disease.