Phenylephrine classification?

Phenylephrine is a direct-acting adrenergic (sympathomimetic) drug.

- Pharmacologic class: selective alpha-1 adrenergic receptor agonist (purely direct-acting; little beta activity).
- Mechanism: causes vasoconstriction via alpha-1 receptors, increasing vascular resistance; in the eye, causes pupil dilation; in the nasal mucosa, reduces edema for decongestion.
- Uses:
- Nasal decongestant (oral or intranasal)
- Ophthalmic mydriatic
- Vasopressor to raise blood pressure (IV) in hypotension/shock
- Forms: oral tablets/capsules, intranasal spray/solution, ophthalmic drops, injectable.
- Important considerations: may raise blood pressure and cause reflex changes in heart rate (often bradycardia); not a beta agonist; interactions with MAO inhibitors and certain antidepressants; caution in hypertension, arrhythmias, and cardiovascular disease.