phenylephrine hydrochloride (NeoSynephrine, Neofrin)
GENERIC NAME: phenylephrine hydrochloride
BRAND NAME: NeoSynephrine, Neofrin
DRUG CLASS AND MECHANISM: Phenylephrine is a man-made drug that stimulates receptors (alpha1 receptors) on blood vessels and cause blood vessels to constrict (vasoconstriction). It is a vasoconstrictor medication, structurally similar to epinephrine and ephedrine. Vasoconstriction increases blood pressure. Phenylephrine increases blood pressure and heart rate without affecting heart rhythm.
GENERIC AVAILABLE: Yes
PREPARATIONS: Injection: 10 mg/ml
STORAGE: Store phenylephrine injections between 15 C to 30 C (59 to 86 F).
PRESCRIBED FOR: Phenylephrine is used for maintenance of blood pressure during anesthesia, for the treatment of vascular failure in shock or shock-like states, drug-induced hypotension, and to overcome paroxysmal supraventricular tachycardia (abnormally fast heart beats) during anesthesia.
DRUG INTERACTIONS: Phenylephrine should be used cautiously with MAO inhibitors like selegiline (Eldepryl, Zelapar), phenelzine (Nardil), isocarboxazid (Marplan), because they can also increase blood pressure and can cause a serious hypertensive episode. A similar reaction occurs when phenylephrine is combined with amphetamine and related drugs.
Phenylephrine should be used with caution with antidepressants like amitriptyline (Elavil, Endep), nortriptyline (Pamelor, Aventyl), doxepin (Sinequan, Adapin), and trazodone (Deyrel). Such anti-depressants may increase blood pressure if used together with phenylephrine.
PREGNANCY: There are no adequate studies done on phenylephrine to determine safe and effective use in pregnant women.
NURSING MOTHERS: It is not known whether phenylephrine enters breast milk; therefore, it is best to be cautious before using it in nursing mothers.
Medically Reviewed by a Doctor on 7/30/2014
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