Oral alpha-adrenergic agonist such associated pseudoephedrine, topical nasal alpha-adrenergic agonists phenylephrine and oxymetazoline vasoconstrict nasal mucosa by stimulating alpha-1adrenergic receptors on venous sinusoids.
Provide relief of nasal congestion.
Oral decongestants may cause insomnia, excitability, nervousness, headaches, palpitations, cardiac arrhythmias, hypertension, nausea, vomiting and urinary retention.
Intranasal decongestants can cause rebound congestion and with prolonged use rhinitis medicamentosa.