1. Clinical Overview
A fixed-dose combination syrup containing a first-generation alkylamine antihistamine (Chlorpheniramine Maleate) and a peripherally-acting antitussive (Levodropropizine). It is primarily indicated for the symptomatic relief of dry, non-productive cough associated with upper respiratory tract infections and allergic conditions. Chlorpheniramine provides anti-allergic and anti-secretory effects, while Levodropropizine acts on sensory neuropeptides in the airways to suppress the cough reflex without central depression.
| Onset | Duration | Bioavailability |
|---|---|---|
| Chlorpheniramine: 30-60 minutes. Levodropropizine: 30-45 minutes. | Chlorpheniramine: 4-6 hours. Levodropropizine: 4-6 hours. | Chlorpheniramine: ~25-50% (oral). Levodropropizine: ~70-80% (oral). |
2. Mechanism of Action
Chlorpheniramine Maleate is a competitive reversible antagonist of histamine at the H1 receptor, inhibiting the physiological effects of histamine (vasodilation, increased capillary permeability, bronchoconstriction). It also possesses anticholinergic and sedative properties. Levodropropizine is the levo-isomer of dropropizine and acts peripherally on sensory neuropeptides (like Substance P) in the respiratory tract. It modulates the activity of C-fibers in the vagus nerve, reducing the sensitivity of the cough reflex arc at the level of the tracheobronchial tree, without depressing the central respiratory centers in the medulla oblongata.
3. Indications & Uses
- Symptomatic relief of dry, non-productive cough associated with upper respiratory tract infections (common cold, viral pharyngitis)
- Allergic cough and cough associated with allergic rhinitis
4. Dosage & Administration
Adult Dosage: 10 ml (2 teaspoonfuls) three times a day. Maximum: 30 ml per day.
Administration: To be taken orally. Use the measuring cup or spoon provided. Can be taken with or without food. Shake the bottle well before use. Maintain adequate hydration.
5. Side Effects
Common side effects may include:
- Drowsiness, sedation, somnolence
- Dryness of mouth, nose, and throat
- Mild dizziness
- Fatigue
- Gastrointestinal discomfort
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| CNS Depressants (Alcohol, Benzodiazepines, Opioids, Barbiturates) | Potentiation of sedative effects, increased risk of respiratory depression. | Major |
| Monoamine Oxidase Inhibitors (MAOIs) - e.g., Phenelzine, Tranylcypromine | Exaggerated anticholinergic and CNS depressant effects, hypertensive crisis risk. | Contraindicated |
| Anticholinergic drugs (Atropine, Tricyclic Antidepressants, Antipsychotics) | Additive anticholinergic side effects (dry mouth, urinary retention, constipation). | Major |
| Other Antihistamines (Cetirizine, Fexofenadine, etc.) | Additive sedative and anticholinergic effects. | Moderate |
| CYP2D6 Inhibitors (Fluoxetine, Paroxetine, Quinidine) | Increased plasma levels and toxicity of Chlorpheniramine. | Moderate |
7. Patient Counselling
- DO take the exact dose as prescribed by your doctor.
- DO shake the bottle well before measuring each dose.
- DO use the measuring device (cup/spoon) provided with the pack.
- DO inform your doctor if cough persists for more than 5 days or is accompanied by fever, rash, or persistent headache.
- DO NOT exceed the recommended dose.
- DO NOT take with alcohol or other sedative medicines.
- DO NOT use for productive cough (cough with phlegm).
- DO NOT give to children under 2 years without doctor's advice.
8. Toxicology & Storage
Overdose: Manifestations are primarily due to Chlorpheniramine: CNS depression (somnolence to coma) or stimulation (insomnia, hallucinations, convulsions), anticholinergic symptoms (fixed dilated pupils, flushing, hyperthermia, urinary retention), cardiovascular effects (tachycardia, hypotension, arrhythmias). Levodropropizine may contribute to nausea and vomiting.
Storage: Store at a temperature not exceeding 30°C. Protect from light and moisture. Keep the bottle tightly closed. Keep out of reach and sight of children. Do not use after the expiry date printed on the label. Discard any unused medicine 4 weeks after opening the bottle.