Dangerous Drug: Phenylephrine Hydrochloride



Dangerous Drug: Phenylephrine Hydrochloride





(fen ill ef’ rin)

Parenteral: Neo-Synephrine

Oral: AH-chew D, Sudafed PE

Oral drops: Little Colds, Decongestant for Infants & Children, PediaCare Children’s Decongestant

Topical OTC nasal decongestants: Little Noses Gentle Formula, Neo-Synephrine, Rhinall, Vicks Sinex Ultra Fine Mist

Strips: Sudafed PE Quick-Dissolve, Thin Strips Decongestant, Triaminic Thin Strips Cold

Ophthalmic preparations (0.12% solutions are OTC): AK-Dilate, Mydfrin, Neo-Synephrine

PREGNANCY CATEGORY C


Drug Classes

Alpha-adrenergic agonist

Nasal decongestant

Ophthalmic vasoconstrictor or mydriatic

Sympathomimetic amine

Vasopressor


Therapeutic Actions

Powerful postsynaptic alpha-adrenergic receptor stimulant that causes vasoconstriction and increased systolic and diastolic BP with little effect on the beta receptors of the heart. Topical application causes vasoconstriction of the mucous membranes, which in turn relieves pressure and promotes drainage of the nasal passages. Topical ophthalmic application causes contraction of the dilator muscles of the pupil (mydriasis), vasoconstriction, and increased outflow of aqueous humor.


Indications

Parenteral



  • Treatment of vascular failure in shock, shocklike states, drug-induced hypotension, or hypersensitivity


  • To overcome paroxysmal supraventricular tachycardia


  • To prolong spinal anesthesia



  • Vasoconstrictor in regional anesthesia


  • To maintain an adequate level of BP during spinal and inhalation anesthesia

Nasal solution and oral



  • Symptomatic relief of nasal and nasopharyngeal mucosal congestion due to the common cold, sinusitis, hay fever, or other respiratory allergies


  • Adjunctive therapy of middle ear infections by decreasing congestion around the eustachian ostia

Ophthalmic solution



  • 10% solution: Decongestant and vasoconstrictor and for pupil dilation in uveitis, wide-angle glaucoma, and surgery


  • 2.5% solution: Decongestant and vasoconstrictor and for pupil dilation in uveitis, open-angle glaucoma in conjunction with miotics, refraction, ophthalmoscopic examination, diagnostic procedures, and before intraocular surgery


  • 0.12% solution: Decongestant to provide temporary relief of minor eye irritations caused by hay fever, colds, dust, wind, smog, or hard contact lenses



Available Forms

Chewable tablets—10 mg; tablets—10 mg; oral drops—2.5 mg/mL, 7.5 mg/5 mL; strips—1.25, 2.5, 10 mg; nasal solution—0.125%, 0.25%, 0.5%, 1%; ophthalmic solution—0.12%, 2.5%, 10%; injection—10 mg/mL


Dosages

Parenteral preparations may be given IM, subcutaneously, by slow IV injection, or as a continuous IV infusion of dilute solutions; for supraventricular tachycardia and emergency use, give by direct IV injection.

Adults

Parenteral



  • Mild to moderate hypotension (adjust dosage on basis of BP response): 1–10 mg subcutaneously or IM; do not exceed an initial dose of 5 mg. A 5-mg IM dose should raise BP for 1–2 hr. Or, for IV use, 0.1–0.5 mg IV. Initial dose should not exceed 0.5 mg. Do not repeat more often than every 10–15 min. 0.5 mg IV should raise the pressure for 15 min.


  • Severe hypotension and shock: For continuous IV infusion, add 10 mg to 500 mL of dextrose injection or sodium chloride injection. Start infusion at 100–180 mcg/min (based on a drop factor of 20 drops/mL; this would be 100–180 drops/min). When BP is stabilized, maintain at 40–60 mcg/min. If prompt vasopressor response is not obtained, add 10-mg increments to infusion bottle.


  • Spinal anesthesia: 2–3 mg subcutaneously or IM 3–4 min before injection of spinal anesthetic.


  • Hypotensive emergencies during anesthesia: Give 0.2 mg IV. Do not exceed 0.5 mg/dose.


  • Prolongation of spinal anesthesia: Addition of 2–5 mg to the anesthetic solution increases the duration of motor block by as much as 50%.


  • Vasoconstrictor for regional anesthesia: 1:20,000 concentration (add 1 mg of phenylephrine to every 20 mL of local anesthetic solution).


  • Paroxysmal supraventricular tachycardia: Rapid IV injection (within 20–30 sec) is recommended. Do not exceed an initial dose of 0.5 mg. Subsequent doses should not exceed the preceding dose by more than 0.1–0.2 mg and should never exceed 1 mg. Use only after other treatments have failed.

Nasal solution

Jul 21, 2016 | Posted by in NURSING | Comments Off on Dangerous Drug: Phenylephrine Hydrochloride

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