Phenylephrine

Phenylephrine

[1 vial $4.75]

ADMINISTRATION ROUTES:

• IV, PO

ALTERNATIVE NAMES:

• Neo-Synephrine

ICU INDICATIONS:

1. hypotension

PRESENTATION AND ADMINISTRATION:

• IV:
  10mg in 1ml (10%) solution
  Add 10mg to 100ml of compatible IV fluid and administered by infusion
  Compatible with the following IV fluids:
  Normal saline, 5% glucose, Glucose and sodium chloride, Hartmanns
  Discard any solution not used within 24 hours of preparation
  Store at room temperature.

DOSAGE:

• IV:
  For hypotension, 100-500mcg PRN For infusion, administer by infusion at 0-60ml/hr (at higher doses, consider commencing noradrenaline)

DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:

• Dose as in normal renal function

DOSAGE IN PAEDIATRICS:

• IV:
  2-10 mcg/kg stat (adult 500mcg), then 1-5mcg/kg/min

CLINICAL PHARMACOLOGY:

• Phenylephrine hydrochloride is a powerful postsynaptic alpha-receptor stimulant with little effect on the beta-receptors of the heart. The predominant actions of phenylephrine hydrochloride are on the cardiovascular system.

CONTRAINDICATIONS:

1. Hypotension solely due to low cardiac output
2. Hypersensitivity to phenylephrine

WARNINGS

• Contains sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.

PRECAUTIONS

• General:
  Phenylephrine hydrochloride should be employed only with extreme caution in elderly patients or in patients with hyperthyroidism, bradycardia, partial heart block, myocardial disease, or severe arteriosclerosis.
• Laboratory Tests: No tests in addition to routine ICU tests are indicated
• Drug/Laboratory Test Interactions: None noted

IMPORTANT DRUG INTERACTIONS FOR THE ICU

• None of note

ADVERSE REACTIONS

• Cardiovascular:
  Arrhythmia (rare), decreased cardiac output, hypertension, pallor, precordial pain or discomfort, reflex bradycardia, severe peripheral and visceral vasoconstriction Central nervous system: Anxiety, dizziness, excitability, giddiness, headache, insomnia, nervousness, restlessness
• Endocrine & metabolic:
  Metabolic acidosis
• Gastrointestinal:
  Gastric irritation, nausea
• Neuromuscular & skeletal:
  Paresthesia, pilomotor response, tremor, weakness
• Renal:
  Decreased renal perfusion, reduced urine output
  
• Respiratory:
  Respiratory distress
• Miscellaneous:
  Hypersensitivity reactions (including rash, urticaria, leukopenia, agranulocytosis, thrombocytopenia)