dihydroergotamine (DHE 45, Migranal)

Introduction

Alias DHE 45. Dihydroergotamine mesylate.

Indications

• prevention & treatment of vascular headaches
• adjunct for DVT prophylaxis for hip surgery
• orthostatic hypotension

Contraindications

• pregnancy
  • oxytocin-like effects can induce labor

pregnancy category = x

safety in lactation = -

Dosage

• 1 mg IV/IM at 1st sign of headache
• repeat in 1 hour PRN, up to 3 mg IM, 2 mg IV
• max dose 6 mg/week (IV)

Injection: 1 mg/mL.

Pharmacokinetics

• onset of action is 15-30 minutes
• extensively metabolized by the liver
• 1/2life is 1.3-3.9 hours
• eliminated predominantly into the bile & feces

elimination via liver

Adverse effects

• common (> 10%)
  • localized edema
  • peripheral vascular effects
    • numbness of fingers & toes
    • paresthesias of fingers & toes
  • drowsiness
  • dizziness
  • dry mouth
  • diarrhea
  • nausea/vomiting
• less common (1-10%)
  • chest pressure/pain, transient tachycardia or bradycardia, muscle pain in extremities, weakness in legs

Drug interactions

• increases effect of heparin
• erythromycin, clarithromycin, nitroglycerin & propranolol increase toxicity

• drug interaction(s) of beta-adrenergic receptor antagonists with ergot alkaloids

Mechanism of action

• vasoconstriction of peripheral & cerebral vessels via direct stimulation of vascular smooth muscle

More general terms

• ergot alkaloid
• anti-migraine agent

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=3066
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=10531