ENT/Other nasal preparations

Nasal decongestants & antihistamines

also: xylometazoline · azelastine · intranasal antihistamine · decongestant

Overview

Adjuncts in rhinitis — intranasal antihistamine for rapid relief; topical decongestants only very short-term (rebound).

Mechanism

Intranasal antihistamines (azelastine) block mucosal H1 receptors — faster onset than oral. Topical decongestants (xylometazoline) are α-adrenergic agonists → mucosal vasoconstriction → ↓congestion, but downregulation causes rebound congestion if used >5–7 days (rhinitis medicamentosa).

Indications

Allergic rhinitis (intranasal antihistamine — fast onset)
Short-term nasal congestion (decongestant)

The agents

Azelastineintranasal antihistamine

rapid

Often combined with fluticasone (Dymista).

Xylometazoline / oxymetazolinetopical α-agonist decongestant

Max ~5–7 days — rebound congestion.

Adverse effects

Rhinitis medicamentosa (rebound congestion)classic

Decongestants used >1 week.

Azelastine: bitter taste, nasal irritationcommon

Decongestant: local stinging, systemic sympathomimetic effects if overusedcommon

Cautions & contraindications

Prolonged decongestant useall

Rebound congestion.

Decongestants in uncontrolled hypertension / cardiovascular diseaseall

Interactions

Sympathomimetic decongestants + MAOIs → hypertensive effects

Monitoring & kinetics

Duration of decongestant use (limit)

Topical nasal. First-line rhinitis = intranasal steroid ± antihistamine; reserve decongestants for short-term.

Source: NICE CKS — Allergic rhinitis · BNF — Nasal preparations