Neurology - Candesartan

Candesartan is used commonly to treat high blood pressure. Although it is not licensed in the UK for treating migraine, studies show that it can be effective, and it is in mainstream use as a migraine preventative.

How should I take candesartan?

• Candesartan is a prescription-only medication that you should obtain from your GP
• It can be started at 4 mg per night increasing by 4 mg every 1 - 2 weeks up to a target dose of 16 mg a day (or highest tolerated dose below this)
• Candesartan can be taken with or without food and should be swallowed whole
• The target dose for migraine prevention is 16 mg a day, but people might benefit from a higher dose, up to 32 mg a day
• Before starting treatment, you should have a routine blood test to check kidney function which should then be repeated at certain doses (8mg, 16mg, 24mg & 32mg)

(Your headache specialist will liaise with your GP to ensure that these are completed).

For how long should I take candesartan?

Candesartan should be taken for 3 months before judging the effectiveness. You should keep a headache diary to record the total number of headache days and severe headache days to track progress. If effective, continue for 9-12 months before starting to reduce slowly, aiming to stop. Sometimes, after controlling migraine effectively for 6-12 months, the medication can be withdrawn. As this isn’t a cure, it might need to be restarted if the headaches become frequent again.

Common potential side effects include:

• Low blood pressure, which can cause dizziness and light headedness
• Impairment of kidney function
• Cough
• Fatigue
• Abdominal pain and back pain

What happens if I do experience side effects?

If you feel that you are experiencing side effects, then it is important to discuss with your GP or headache specialist team.

Can I take other medications when taking candesartan?

Your headache specialist will review your current medications before starting candesartan.

Candesartan should be avoided in patients with

• Narrowing of heart valves (e.g. aortic stenosis)
• Low blood pressure
• High potassium level
• A history of angioedema
• Have narrowed arteries feeding the kidneys (renal artery stenosis)

Pregnancy and breast feeding

This should be avoided in pregnancy and breast feeding. If you fall pregnant while taking this drug for migraine, it should be reduced and stopped. You should see your GP urgently about that.