Bricanyl Turbohaler

Bricanyl is a short-acting bronchodilator containing terbutaline sulphate, used for the rapid relief of bronchospasm in patients with asthma and chronic obstructive pulmonary disease (COPD). It works quickly to open the airways during an acute episode of wheeze, breathlessness, or chest tightness, providing symptomatic relief within minutes of administration. Bricanyl is available in the UK as a Turbohaler (a dry powder inhaler) and as a solution for injection and infusion, with the Turbohaler being the most commonly used form for maintenance and acute relief in asthma.

How Bricanyl Works

Terbutaline is a selective beta-2 adrenoceptor agonist. By binding to beta-2 receptors on the smooth muscle cells lining the walls of the bronchi and bronchioles, terbutaline stimulates the production of cyclic adenosine monophosphate (cAMP), which activates protein kinase A and leads to smooth muscle relaxation. This bronchodilatory effect widens the airways and reduces the resistance to airflow, allowing the patient to breathe more easily. The effect is rapid in onset, within one to two minutes of inhalation, and lasts for approximately three to five hours.

Reliever Role in Asthma Management

Bricanyl is classified as a reliever inhaler and is used to manage acute symptoms rather than to prevent them. It should not replace regular anti-inflammatory preventer therapy (such as an inhaled corticosteroid like beclometasone or budesonide) in patients with persistent asthma. Guidelines recommend that the frequency of reliever inhaler use is an important marker of asthma control: needing to use a reliever more than twice per week (excluding use before exercise) suggests that preventer therapy should be reviewed and potentially stepped up.

Turbohaler Device

The Bricanyl Turbohaler is a breath-actuated dry powder inhaler that requires no manual co-ordination between pressing and inhaling, making it particularly suitable for patients who find pressurised metered-dose inhalers (MDIs) difficult to use. The device has a built-in dose counter so patients can monitor how many doses remain.

Using the Bricanyl Turbohaler

The Bricanyl Turbohaler is used by inhaling sharply and deeply through the mouthpiece after loading a dose by turning the grip at the bottom of the device clockwise and then anticlockwise until it clicks. The device requires a fast, forceful inhalation to generate sufficient airflow to disperse the dry powder into respirable particles. Unlike MDIs, there is no aerosol released, so patients may not feel much sensation during inhalation; this does not mean the dose has not been delivered.

After each use, the mouthpiece cap should be replaced. The Turbohaler should be kept dry and the mouthpiece should not be washed; if cleaning is required, the outside can be wiped with a dry cloth. The device is single-patient use and should not be shared.

When to Use Bricanyl

For acute relief of asthma symptoms, the usual dose is one actuation (500 micrograms), repeated after five minutes if initial relief is insufficient. If three or more actuations are needed to control a single episode, or if symptoms are not relieved within 20 minutes, the patient should seek urgent medical attention, as this may indicate a severe or life-threatening asthma attack. For exercise-induced bronchospasm, one actuation may be taken 10 to 15 minutes before exercise.

If a patient finds they are using their Bricanyl reliever more than twice per week, they should discuss this with their GP or asthma nurse, as it indicates suboptimal asthma control.

For adults and children aged 12 years and over, the usual dose via the Bricanyl Turbohaler is one actuation (500 micrograms of terbutaline sulphate) as needed for acute bronchospasm, up to a maximum of four actuations per day on a regular basis. For acute symptom relief, doses may be repeated every four to six hours as needed. Total daily inhaled doses should not normally exceed 4 mg (8 actuations) except under medical supervision during severe exacerbations.

For children aged 5 to 11 years, the dose is one actuation (500 micrograms) as needed, with the same daily maximum. The Turbohaler requires a sufficiently forceful inhalation effort and may not be appropriate for very young children who cannot generate adequate inspiratory flow; alternative spacer-compatible devices may be recommended.

Elderly patients do not require routine dose adjustment, though they may have slower clearance of terbutaline and should be monitored for cardiovascular side effects. Patients with significant renal impairment should use terbutaline with caution, as the drug is primarily renally excreted, and accumulation can increase the risk of systemic side effects including tremor and tachycardia.

Bricanyl is generally well tolerated when used as directed at the recommended doses. Side effects are largely predictable from its beta-2 agonist pharmacology.

Common Side Effects

The following are frequently reported:

• Tremor (shakiness of the hands or fingers), the most common side effect, typically mild and improving with continued use
• Palpitations (awareness of the heartbeat)
• Tachycardia (increased heart rate)
• Headache
• Muscle cramps
• Nervousness or restlessness, particularly after high doses

Serious Side Effects

The following require medical assessment:

• Severe tachycardia or cardiac arrhythmias: very high doses can cause clinically significant cardiac rhythm disturbances, particularly in patients with pre-existing heart disease
• Hypokalaemia (low potassium): high doses or frequent use of beta-2 agonists can lower serum potassium levels, which may exacerbate cardiac arrhythmias, relevant in acute severe asthma managed with high-dose nebulised terbutaline
• Paradoxical bronchospasm: rarely, inhaled bronchodilators can provoke immediate worsening of bronchospasm, if this occurs, the inhaler should be discontinued immediately and an alternative bronchodilator used
• Hypersensitivity reactions: anaphylaxis or severe allergic reactions are rare but have been reported
• Worsening hyperglycaemia in patients with diabetes, particularly with high-dose or intravenous terbutaline

Acute Severe Asthma

Bricanyl is a reliever inhaler for mild to moderate acute symptoms and is not a treatment for severe or life-threatening asthma attacks. If a patient requires more than eight actuations of their reliever inhaler in a 24-hour period, or if symptoms are not improving despite repeated doses, emergency medical help must be sought immediately. Signs of severe asthma include an inability to complete a sentence, cyanosis (blue lips or fingernails), an increasing respiratory rate, and exhaustion -- all require emergency treatment with high-flow oxygen, nebulised bronchodilators, and systemic corticosteroids.

Cardiovascular Cautions

Beta-2 agonists including terbutaline can increase heart rate and cause palpitations, which are usually benign at standard doses. In patients with pre-existing cardiac arrhythmias, ischaemic heart disease, or hypertrophic obstructive cardiomyopathy, terbutaline should be used with caution and the lowest effective dose employed. Concurrent use with monoamine oxidase inhibitors (MAOIs) or tricyclic antidepressants potentiates the cardiovascular effects of terbutaline and is generally contraindicated.

Hypokalaemia Risk

Frequent use of high doses of inhaled beta-2 agonists, particularly in combination with theophylline, corticosteroids, or loop diuretics, can cause a significant fall in serum potassium. This is especially relevant during acute severe asthma management in hospital, where nebulised terbutaline may be administered at high doses. Serum potassium should be monitored in these circumstances.

Bricanyl must not be used in the following circumstances:

• Known hypersensitivity to terbutaline sulphate or any excipient in the Turbohaler formulation
• As the sole or primary treatment for chronic asthma in patients who do not have a preventer inhaler prescribed (a preventer is required for all but the mildest intermittent asthma)
• Concurrent use with non-selective beta-blockers (such as propranolol), as they antagonise the bronchodilatory effect of terbutaline and can provoke severe bronchospasm
• During known or threatened premature labour (injectable terbutaline is sometimes used for tocolysis under specialist supervision, but this is a different clinical context)
• In patients with severe pre-existing cardiac arrhythmias without cardiology review and supervision