Function

• Although doctors do not understand why, medications typically used to lower blood pressure levels also help reduce the frequency of migraine headaches and the severity of symptoms when they do occur, explains the Mayo Clinic.
  
  

Types

• Antihypertensive medications for migraines include beta blockers like metoprolol and propranolol, calcium channel blockers like verapamil, ACE inhibitors like lisinopril and angiotensin II receptor antagonist like candesaratan.
  
  

Time Frame

• Doctors typically prescribe antihypertensive medications for migraines for use daily. Once symptoms of migraines subside for six months to one year, your doctor is likely to recommend tapering off your dosage of antihypertensive medications, explains the Mayo Clinic.
  
  

Risks

• Possible side effects of antihypertensive medications for migraines include constipation, dizziness, increased sensitivity to cold or sunlight, drowsiness, potassium deficiency, bleeding gums and nausea, according to Johns Hopkins University.
  
  

Considerations

• You may need to try several different antihypertensive medications before you find one that is effective in reducing the frequency and severity of your migraine and that also causes few or no side effects.