Guaifenesin / Chlorpheniramine / Phenylephrine

What it is and how it works

Guaifenesin is an expectorant thought to increase the volume and reduce the viscosity of respiratory secretions. Chlorphenamine is a first-generation H1-antihistamine that reduces rhinorrhoea and sneezing, and phenylephrine is an alpha1-adrenergic agonist that causes nasal vasoconstriction and relieves congestion.

Indications

Short-term symptomatic relief of productive cough with nasal congestion, rhinorrhoea and sneezing associated with the common cold, upper respiratory tract infections or allergic rhinitis.

Contraindications

Concomitant MAO inhibitors or within 14 days of stopping them; severe hypertension or coronary artery disease; hyperthyroidism; angle-closure glaucoma; urinary retention or prostatic hypertrophy; young children below the age stated on the label (generally under 6 years).

Warnings and precautions

Chlorphenamine causes drowsiness and impairs ability to drive; effects are potentiated by alcohol and other CNS depressants. Use with caution in hypertension, cardiovascular disease, diabetes, epilepsy and in the elderly; avoid combining with other sympathomimetic or antihistamine-containing products. Seek medical advice if cough persists for more than a week or is accompanied by high fever.

Pregnancy

Avoid in pregnancy, particularly in the first trimester, because of the decongestant component.

Storage and supply

Store below 25 °C, protected from light.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.