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Related to Neo-Synephrine: Afrin


(fen-il-eff-rin) ,


(trade name)


Therapeutic: vasopressors
Pharmacologic: adrenergics
Pregnancy Category: B
Pregnancy Category: C (Ophth, Parenteral)
For ophthalmic use see


Management of hypotension associated with shock that may persist after adequate fluid replacement.Management of hypotension associated with anesthesia.Anesthesia adjunct:
  • Prolongation of the duration of spinal anesthesia,
  • Localization of the effect of regional anesthesia.


Constricts blood vessels by stimulating alpha-adrenergic receptors.

Therapeutic effects

Increased BP.


Absorption: Well absorbed from IM sites.
Distribution: Unknown.
Metabolism and Excretion: Metabolized by the liver and other tissues.
Half-life: 2.5 hr.

Time/action profile (vasopressor effects)

IVimmediateunknown15–20 min
IM10–15 minunknown0.5–2 hr
Subcut10–15 minunknown50–60 min


Contraindicated in: Uncorrected fluid volume deficits;Tachyarrhythmias;Pheochromocytoma;Angle-closure glaucoma;Acute pancreatitis;Hepatitis;Hypersensitivity to bisulfites.
Use Cautiously in: Occlusive vascular diseases;Cardiovascular disease;Diabetes mellitus; Obstetric / Lactation: Safety not established.
Exercise Extreme Caution in: Geriatric: More likely to experience adverse reactions, which result in hallucinations, convulsions, CNS depression, and death;Hyperthyroidism;Bradycardia;Partial heart block;Severe cardiovascular disease.

Adverse Reactions/Side Effects

Central nervous system

  • anxiety
  • dizziness
  • headache
  • insomnia
  • nervousness
  • restlessness
  • trembling
  • weakness


  • dyspnea
  • respiratory distress


  • arrhythmias (life-threatening)
  • bradycardia
  • chest pain
  • hypertension
  • tachycardia
  • vasoconstriction


  • blanching
  • pallor
  • piloerection
  • sweating


  • phlebitis
  • sloughing at IV sites


  • tremor


Drug-Drug interaction

Use with general anesthetics may result in myocardial irritability; use with extreme caution.Use with MAO inhibitors, ergot alkaloids (ergonovine, methylergonovine ), or oxytocics results in severe hypertension.Alpha-adrenergic blockers (phentolamine ) may antagonize vasopressor effects.Atropine blocks bradycardia from phenylephrine and enhances pressor effects.



Subcutaneous Intramuscular (Adults) 2–5 mg.
Subcutaneous Intramuscular (Children) 0.1 mg/kg/dose q 1–2 hr as needed, maximum dose 5 mg.
Intravenous (Adults) 0.2 mg (range 0.1–0.5 mg), may be repeated q 10–15 min or as an infusion at 100–180 mcg/min initially, 40–60 mcg/min maintenance.
Intravenous (Children) 5–20 mcg/kg/dose q 10–15 min as needed or 0.1–0.5 mcg/kg/min infusion, titrate to effect.

Hypotension during Spinal Anesthesia

Subcutaneous Intramuscular (Adults) 2–3 mg has been used 3–4 min before spinal anesthesia to prevent hypotension.
Intramuscular Subcutaneous (Children) —0.5–1 mg/25 lb body weight.
Intravenous (Adults) 0.2 mg; may repeat q 10–15 min and may be ↑ by 0.1–0.2 mg/dose (not to exceed 0.5 mg/dose).

Vasoconstrictor for Regional Anesthesia

Local: (Adults) Add 1 mg to every 20 mL of local anesthetic (yields a 1:20,000 solution).

Prolongation of Spinal Anesthesia

Spinal: (Adults) 2–5 mg added to anesthetic solution.

Availability (generic available)

Injection: 10 mg/mL

Nursing implications

Nursing assessment

  • Monitor BP every 2–3 min until stabilized and every 5 min thereafter during IV administration.
    • Monitor ECG continuously for arrhythmias during IV administration.
    • Assess IV site frequently throughout infusion. Antecubital or other large vein should be used to minimize risk of extravasation, which may cause tissue necrosis. If extravasation occurs, the site should be infiltrated promptly with 10–15 mL of 0.9% NaCl solution containing 5–10 mg of phentolamine to prevent necrosis and sloughing.

Potential Nursing Diagnoses

Decreased cardiac output (Indications)
Ineffective tissue perfusion (Indications)


  • high alert: Patient harm and fatalities have occurred from medication errors with phenylephrine. Prior to administration, have second practitioner independently check original order, dose calculations, concentration, route of administration and infusion pump settings.
  • Intravenous Administration
  • Intravenous: Blood volume depletion should be corrected, if possible, before initiation of IV phenylephrine.
  • Diluent: Dilute each 1 mg with 9 mL of sterile water for injection.
  • Rate: Administer each single dose over 1 min.
  • Continuous Infusion: Diluent: Dilute 10 mg in 250 or 500 mL of dextrose/Ringer’s or lactated Ringer’s combination, dextrose/saline combinations, D5W, D10W, Ringer’s or LR, 0.45% NaCl, or 0.9% NaCl.Concentration: 125,000 or 150,000 solution, respectively.
  • Rate: Titrate rate according to patient response. Infuse via infusion pump to ensure accurate dose rate.
  • Y-Site Compatibility: alfentanil, amikacin, aminophylline, amiodarone, amphotericin B liposome, anidulafungin, argatroban, ascorbic acid, atropine, aztreonam, benztropine, bivalirudin, bleomycin, bumetanide, buprenorphine, butorphanol, calcium chloride, calcium gluconate, carboplatin, carmustine, caspofungin, cefazolin, cefonocid, cefoperazone, cefotaxime, cefotetan, cefoxitin, ceftazidime, cephalothin, chloramphenicol, cisatracurium, cisplatin, clindamycin, cyanocobalamin, cyclophosphamide, cyclosporine, cytarabine, dactinomycin, daptomycin, dexamethasone, dexmedetomidine, digoxin, diltiazem, diphenhydramine, dobutamine, docetaxel, dopamine, doripenem, doxorubicin hydrochloride, doxycycline, enalaprilat, ephedrine, epinephrine, epirubicin, epoetin alfa, eptifibatide, ertapenem, erythromycin, esmolol, etomidate, etoposide, etoposide phosphate, famotidine, fenoldopam, fentanyl, fluconazole, fludarabine, fluorouracil, folic acid, gentamicin, glycopyrrolate, granisetron, heparin, hetastarch, hydrocortisone, hydromorphone, idarubicin, ifosfamide, imipenem/cilastatin, irinotecan, isoproterenol, ketorolac, labetalol, levofloxacin, lidocaine, linezolid, lorazepam, magnesium sulfate, mannitol, mechlorethamine, meperidine, methotraxate, methoxamine, methyldopate, methtylprednisolone, metoclopramide, metoprolol, metronidazole, micafungin, miconazole, midazolam, milrinone, mitoxantrone, morphine, multivitamins, mycophenolate, nafcillin, nalbuphine, naloxone, nitroglycerin, nitroprusside, norepinephrine, octreotide, ondansetron, oxacillin, oxaliplatin, oxytocin, paclitaxel, palonsetron, pantoprazole, papaverine, penicillin G, pentobarbi1tol, phenobarbitol, phentolamine, phytonadione, piperacillin/tazobactam, potassium acetate, potassium chloride, procainamide, prochlorperazine, promethazine, propranolol, protamine, pyridoxime, quinupristin/dalfopristin, ranitidine, remifentanil, rocuronium, sodium acetate, sodium bicarbonate, streptokinase, succinylcholine, sufentanil, tacrolimus, telavancin, teniposide, theophylline, thiamine, thiotepa, ticarcillin/clavulanate, tigecycline, tirofiban, tobramycin, tolazoline, vancomycin, vasopressin, vecuronium, verapamil, vincristine, vinorelbine, voriconazole, zidovudine, zoledronic acid
  • Y-Site Incompatibility: acyclovir, amphotericin B colloidal, azathioprine, dantrolene, diazepam, diazoxide, furosemide, ganciclovir, indomethacin, insulin, pentamidine, phenytoin, trimethoprim/sulfamethoxazole, thiopental
  • Anesthesia: Phenylephrine 2–5 mg may be added to spinal anesthetic solution to prolong anesthesia.
    • Phenylephrine 1 mg may be added to each 20 mL of local anesthetic to produce vasoconstriction.

Patient/Family Teaching

  • Intravenous: Instruct patient to report headache, dizziness, dyspnea, or pain at IV infusion site promptly.

Evaluation/Desired Outcomes

  • Increase in BP to normal range.
  • Prolonged duration of spinal anesthesia.
  • Localization of regional anesthesia.


A trademark for an over-the-counter nasal decongestant containing the hydrochloride form of either phenylephrine or oxymetazoline.
References in periodicals archive ?
(+5.4%) Market Unit sales Unit sales LEADING BRANDS ** share (000) % change Afrin 8.2% 3,328 - 2.6% Zicam 7.7% 3,093 + 6.5% Afrin No Drip 4.7% 1,889 + 1.0% Vicks Sinex 4.0% 1,615 - 0.1% Blairex Simply Saline 3.7% 1,490 + 23.2% Ayr 3.6% 1,438 + 16.9% Vicks 3.3% 1,319 - 5.2% Sudacare Shower Soothers 2.7% 1,099 + 12.1% Neo-Synephrine 2.6% 1,047 + 4.7% Sudacare Vapor Plug 2.4% 975 - 19.6% * Total of drug stores, supermarkets and discount stores excluding Wal-Mart Stores Inc.
That day saw the approval of such ingredients as 4 mg chlorpheniramine maleate (used in such products as Allerest, Chlor-Trimeton and Contac), oxmetazoline hydrochloride 0.05% aqueous solution (Afrin, Dristan Long Lasting and Neo-Synephrine 12-Hour) and pseudoephedrine hydrochloride 60 mg (Sudafed).
In the cough/cold category Bayer offers Alka-Seltzer Plus as well as NaSal Neo-Synephrine saline moisturizer and Neo-Synephrine nasal spray.