trimethaphan (Arfonad)

Tradename: Arfonad. Dosage: - 500 mg 100 mL D5W (5 mg/mL) IV at 1-10 mg/min (12-120 mL/hr). - IV infusion 0.5-4 mg/minute. Adverse effects: 1) tachyphylaxis to this drug tends to develop within 24 hours of use 2) adynamic ileus 3) acute urinary retention 4) muscle paralysis with respiratory failure Mechanism of action: Trimethaphan's effects are directed at the sympathetic ganglia. Its major advantages over other drugs in treatment of hypertensive crisis is a reduction of both BP & shear forces on the aortic wall. Thus trimethaphan is considered an alternative first line agent in the treatment of aortic dissection.

Interactions

drug interactions drug adverse effects of antihypertensive agents

Properties

MISC-INFO: elimination route LIVER onset-of-action 1-5 MIN {IV} 1/2life 1-5 MIN

References

The Pharmacological Basis of Therapeutics, 9th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1996