A fixed-dose combination of a second-generation, non-sedating antihistamine (Fexofenadine) and a sympathomimetic decongestant (Phenylephrine). It is primarily indicated for the symptomatic relief of allergic rhinitis and the common cold, providing relief from sneezing, rhinorrhea, nasal congestion, and itchy/watery eyes. Fexofenadine is a selective peripheral H1-receptor antagonist, while Phenylephrine is a selective α1-adrenergic receptor agonist that causes vasoconstriction in the nasal mucosa.
Adult: 10 ml (2 teaspoonfuls) orally twice daily. Each 5ml contains Fexofenadine 30mg and Phenylephrine 2.5mg.
Note: Shake the bottle well before use. Use the measuring cup/spoon provided. Can be taken with or without food. Avoid taking with fruit juices (apple, orange, grapefruit) as they can reduce Fexofenadine absorption. Maintain adequate fluid intake.
Fexofenadine competitively inhibits histamine binding at the H1-receptor in the respiratory tract, blood vessels, and gastrointestinal tract, preventing allergic symptoms. Phenylephrine acts as a direct sympathomimetic agonist on α1-adrenergic receptors in the vascular smooth muscle of the nasal mucosa, causing vasoconstriction, reduced edema, and decreased nasal congestion.
Pregnancy: Category C (US FDA). Animal studies are inadequate. Use only if potential benefit justifies potential risk to the fetus, especially in the first trimester. Phenylephrine may reduce uterine blood flow.
Driving: Generally safe as Fexofenadine is non-sedating. However, patients should be cautioned that individual responses vary; if drowsiness or dizziness occurs, they should not drive or operate machinery.
| Monoamine Oxidase Inhibitors (MAOIs) - e.g., Phenelzine, Selegiline | Markedly potentiates pressor effects of Phenylephrine, leading to hypertensive crisis. | Contraindicated |
| Beta-blockers (e.g., Propranolol) | Unopposed alpha-adrenergic activity may lead to severe hypertension and bradycardia. | Major |
| Other Sympathomimetics (e.g., Pseudoephedrine, Decongestant cold remedies) | Additive adrenergic effects, increasing risk of hypertension, tachycardia, and CNS stimulation. | Major |
| Antihypertensives (e.g., Alpha-blockers, Beta-blockers, Diuretics) | Phenylephrine may antagonize the hypotensive effect. | Moderate |
| Erythromycin, Ketoconazole | May increase Fexofenadine plasma levels via P-glycoprotein inhibition, potentially increasing side effects. | Moderate |
| Anticholinergics (e.g., Atropine, TCAs) | Additive anticholinergic effects (dry mouth, urinary retention, blurred vision). | Moderate |
| Alcohol, CNS Depressants | Although Fexofenadine is non-sedating, additive sedation may occur in sensitive individuals. | Moderate |