Adult Dosing
Adjunctive to spinal anesthesia
- Add 2-5 mg to anesthesia solution
Paroxysmal supraventricular tachycardia
- 0.5 mg IV x1; may increase by 0.1-0.2 mg/dose
- Max: 1 mg/dose
Prophylaxis of hypotension associated with spinal anesthesia
- 2-3 mg SC/IM x1; administer 3-4 minutes prior to anesthetic procedure
Hypotensive emergency associated with spinal anesthesia
- 0.1-0.5 mg IV q10-15 minutes
- Initiate: 0.2 mg IV initial dose
- Max: 0.5 mg/dose
Mild-moderate hypotension
- 0.1-0.5 mg IV q10-15 minutes
- Max: 0.5 mg/dose IV or 5 mg/dose SC/IM
- Alt: 2-5 mg SC/IM q1-2 hrs PRN
Shock
- 40-60 mcg/minute IV
- Start: 100-180 mcg/minute IV until blood pressure is stabilized
Pediatric Dosing
Hypotensive emergency associated with spinal anesthesia
- 2-12 yrs
- 0.044-0.088 mg/kg SC/IM x1
Mild-moderate hypotension
- 2-12 yrs
- 0.1 mg/kg SC/IM q1-2 hrs PRN
- Max: 5 mg/dose
Paroxysmal supraventricular tachycardia
Shock
- 2-12 yrs
- 5-20 mcg/kg IV bolus, then 0.1-0.5 mcg/kg/minute IV
- Max: 3-5 mcg/kg/minute IV
[Outline]
- The pressor effects of sympathomimetic pressor amines are potentiated on concomitant use with oxytocic drugs. Warn the obstetrician that certain oxytocic drugs may cause severe persistent hypertension and may even rupture cerebral blood vessel during the postpartum period
- Allergic-type reactions including anaphylactic symptoms and life threatening or less severe asthmatic episodes may occur in certain susceptible individuals due to presence of sodium metabisulfite
Cautions: Use cautiously in
- Hypersensitivity to sulfites
- Asthma
- Hyperthyroidism
- Bradycardia
- Partial heart block
- Myocardial disease
- Severe arteriosclerosis
- Diabetes mellitus
- Thyroid disorder
- Prostatic hypertrophy
- Geriatrics
Pregnancy Category:C
Breastfeeding: Milk production might decrease on intravenous administration of phenylephrine. This information is based on LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 26 April 2011). Manufacturer advises caution.
