Mephentermine (Wyamine)

Category:

• Nervous system

Description:

• Antihypotensive

Indications:

• Hypotension during spinal anesthesia

Contraindications:

• Hypotension induced by chlorpromazine

• Concurrent use with any MAOI

Precautions:

• Pregnancy category C

• Cardiovascular disease, chronically ill patients

• Hemorrhagic shock, hyperthyroidism, hypertension

Adverse Reactions (Side Effects):

• CNS: anxiety, confusion, drowsiness, incoherence, tremors

• CV: hypertension, palpitations, tachydardia

Dosage:

Administered intramuscularly, intravenously

• Adult:            

  • Prevention of hypotension during spinal anesthesia: 

    • IM 30-45mg 10-20 minutes prior to anesthesia      

  • Hypotension following spinal anesthesia: 

    • IV 30-45mg, repeat doses of 30mg as needed to maintain blood pressure

    • IV INF use 0.1% solution in D5W (1mg/ml), titrate to patient response