1. Clinical Overview
A fixed-dose combination syrup containing a selective beta-2 adrenergic agonist (Terbutaline) and a mucolytic agent (Bromhexine). It is primarily indicated for the symptomatic treatment of acute and chronic bronchospastic conditions associated with excessive, viscous mucus, such as in bronchitis, asthma, and COPD. Terbutaline provides rapid bronchodilation, while Bromhexine thins and loosens bronchial secretions, facilitating expectoration.
| Onset | Duration | Bioavailability |
|---|---|---|
| Terbutaline: 15-30 minutes (oral). Bromhexine: Mucolytic effect begins within 2-3 days of regular dosing. | Terbutaline: 4-8 hours (oral). Bromhexine: Effect persists for several hours. | Terbutaline: Approximately 33-50% (oral, subject to significant first-pass metabolism). Bromhexine: Nearly complete (~100%). |
2. Mechanism of Action
Terbutaline selectively stimulates beta-2 adrenergic receptors on bronchial smooth muscle, leading to activation of adenylate cyclase, increased intracellular cAMP, and subsequent relaxation of smooth muscle, resulting in bronchodilation. Bromhexine depolymerizes and lyses acid mucopolysaccharide fibers in bronchial mucus, reducing its viscosity. It also stimulates the production of serous (less viscous) secretions and activates the ciliary apparatus, improving mucociliary clearance.
3. Indications & Uses
- Symptomatic treatment of acute exacerbations of chronic obstructive pulmonary disease (COPD)
- Bronchial asthma (for relief of bronchospasm and associated tenacious mucus)
- Acute and chronic bronchitis with bronchospasm and viscous sputum
4. Dosage & Administration
Adult Dosage: 10 ml (one 5ml spoonful twice) two to three times daily. Maximum: 30 ml (6 spoonfuls) per day.
Administration: Should be taken orally, preferably after meals to minimize gastric irritation. Use the measuring cup or spoon provided. Drink a full glass of water after each dose to help loosen mucus. Do not take immediately before bedtime to avoid disruption of sleep due to cough expectoration.
5. Side Effects
Common side effects may include:
- Fine tremor (especially hands)
- Headache
- Nervousness, restlessness
- Palpitations, tachycardia
- Mild nausea, gastrointestinal discomfort
- Taste disturbance
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Beta-blockers (e.g., Propranolol) | Antagonizes bronchodilator effect of terbutaline; may cause severe bronchospasm in asthmatics. | Major |
| Diuretics (especially loop and thiazide) | Increased risk of hypokalemia due to additive effect with terbutaline. | Major |
| Monoamine Oxidase Inhibitors (MAOIs) & Tricyclic Antidepressants (TCAs) | Potentiates the cardiovascular effects (tachycardia, hypertension) of terbutaline. | Major |
| Other Sympathomimetics (e.g., decongestants, other asthma drugs) | Additive sympathetic effects, increasing risk of tachycardia and hypertension. | Moderate |
| Digoxin | Hypokalemia induced by terbutaline may increase risk of digoxin toxicity. | Moderate |
| Xanthine derivatives (Theophylline) | Additive stimulant effects; increased risk of tachycardia and CNS stimulation. | Moderate |
| Corticosteroids (systemic) | Increased risk of hypokalemia. | Moderate |
7. Patient Counselling
- DO take the exact dose prescribed by your doctor.
- DO use the measuring device provided with the syrup.
- DO drink plenty of warm fluids (water) while taking this medicine to help thin the mucus.
- DO report if your breathing gets worse or if you need to use your quick-relief inhaler more often.
- DONT take this medicine if you are allergic to any ingredient.
- DONT exceed the recommended dose to avoid serious side effects like fast heartbeat and tremor.
- DONT take other cough/cold medicines without consulting your doctor.
8. Toxicology & Storage
Overdose: Terbutaline predominance: Severe tachycardia, angina, hypertension or hypotension, arrhythmias, profound hypokalemia, nervousness, headache, tremor, seizures, metabolic acidosis. Bromhexine: Nausea, vomiting, diarrhea, abdominal pain.
Storage: Store at room temperature (15-25°C), protected from light and moisture. Keep the bottle tightly closed. Keep out of reach of children. Do not use after the expiry date printed on the label. Do not freeze.