Phenylephrine

DEA Class;  Rx

Common Brand Names; Vazculep, Biorphen

Phenylephrine ophthalmic: Altafrin, Neofrin, Refresh Redness Relief

Phenylephrine nasal (OTC): NeoSynephrine Nasal, Neo-Synephrine Cold & Sinus Mild Strength Spray

  • Alpha1 Agonists
  • Cycloplegics/Mydriatics; 
  • Alpha Agonists, Ophthalmic
  • Decongestants, Intranasal

Synthetic sympathomimetic amine with selective alpha-1 adrenergic agonist effects
Used orally and intranasally as decongestant, ophthalmically to produce mydriasis for examination or procedures, and parenterally as a vasopressor
Adverse reactions due to excessive pharmacologic activity

Alpha-1 adrenergic receptor agonist indicated for treatment of clinically important hypotension resulting primarily from vasodilation in the setting of anesthesia

For mydriasis induction before ophthalmic procedures or examination.
For the treatment of paroxysmal supraventricular tachycardia (PSVT).
For the treatment of hypotension or shock.
For severe hypotension or shock (e.g., drug-induced severe hypotension, septic shock†, traumatic brain injury (TBI)).
For use during spinal anesthesia.
For the treatment of sinus and nasal congestion and eustachian tube congestion due to the common cold, allergic rhinitis, or sinusitis.
For the treatment of internal and external symptoms of hemorrhoids.
For the treatment of hypercyanotic episodes associated with tetralogy of fallot (i.e., tetralogy spells).
 

Hypersensitivity, narrow-angle glaucoma, ventricular tachycardia, hypertension

Phenylephrine

  • Extravasation
  • Hypertension
  • Reflex bradycardia
  • Anxiety
  • Headache
  • Burning
  • Rebound congestion
  • Sneezing
  • Pulmonary edema
  • Metabolic acidosis
  • Decreased renal perfusion
  • Reduced urine output
  • Nausea
  • Gastric irritation

Phenylephrine ophthalmic (Rx, OTC)

  • Frequent: transient burning or stinging
  • Arrhythmia
  • Myocardial infarction
  • Subarachnoid hemorrhage
  • Headache or browache
  • Blurred vision
  • Syncope
  • Rebound myosis
  • Reactive hyperemia
  • Transient keratitis
  • Hypersensitivity reactions such as allergic conjunctivitis or dermatitis
  • Sensitivity to light

Phenylephrine nasal (OTC)

  • Stinging
  • Dryness
  • Rebound congestion
  • Sneezing
  • Burning

Reduce dose if used within 21 d of MAO inhibitors or TCAs

Wait 5 min between multiple drops (no >3 drops needed)

Rebound miosis may occur in elderly people 1 day after treatmentwith phenylephrine

Notify healthcare provider if vision changes, worsening of symptoms, or continued redness occur

Caution with marked hypertension, cardiac disorders, advanced arteriosclerotic changes, type 1 diabetes mellitus, hyperthyroidism; in children of low body weight; elderly

May cause false-normal tonometry readings, tonometry should be performed before phenylephrine is administered

Presence of sulfites in some products may cause allergic reactions in susceptible patients

Data from randomized controlled trials and meta-analyses with use in pregnant women during caesarean section have not established a drug-associated risk of major birth defects and miscarriage

No data available on the presence of phenylephrine injection or its metabolite in human or animal milk, the effects on the breastfed infant, or the effects on milk production

Phenylephrine nasal (OTC)

Pregnancy Category: C

Lactation: not known if excreted in breast milk

NOTE: For certain indications and routes of administration, phenylephrine dosage must be individualized and is highly variable depending on the nature and severity of the disease and on patient response; do not exceed recommended dosage limits for the specific product prescribed; the following are general guidelines:
 

Adult

Severe Hypotension/Shock

IV bolus: 40-100 mcg q1-2 min PRN, not to exceed total dose of 200 mcg

Adjust dosage according to blood pressure goal

Continuous IV infusion: If blood pressure is below the target goal, start a continuous IV infusion with an infusion rate of 10-35 mcg/min; not to exceed 200 mcg/min

Mydriasis Production

Ophthalmoscopy: 1-2 gtt 2.5% solution or 10% solution, may repeat in 10-60 min, mydriasis persists >3 hr, no cycloplegia

Ocular Surgery: 1-2 gtt 2.5% or 10% solution administered 30-60 min preop

Irrigation: 1-2 gtt 0.12% solution into affected eye up to four times daily; not to exceed 72 hr of therapy

Posterior Synechiae Prevention

Anterior Uveitis: 1 gtt of 10% solution three times daily or more (with atropine);

Post-iridectomy: 1 gtt of 10% solution qDay or twice daily

Eye Redness

OTC strength (0.12%) may be used to decrease appearance of eye redness (bloodshot eyes)

Instill 1-2 gtt in affected eye(s) BID/TID

Nasal Congestion

Instill 2-3 sprays or 2-3 gtt q4hr of 0.25-0.1% solution PRN; not to exceed 3 days

Phenylephrine hydrochloride

injectable IV solution (ready-to-use)

  • 0.1 mg/mL (Biorphen)

  • Do not dilute further

injectable IV solution (concentrated)

  • 10mg/mL (Vazculep, Biorphen)

  • Requires further dilution

ophthalmic solution

  • 0.12% (OTC; Refresh Redness Relief)

  • 2.5% (Rx; Altafrin, Neofrin)

  • 10% (Rx; Altafrin, Neofrin)

nasal spray

  • 0.25%

  • 0.5%

  • 1%

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