What dose of candesartan (angiotensin II receptor antagonist) is used for treating headaches?

Candesartan Dosing for Headache Prevention

Candesartan should be prescribed at a dose of 16 mg once daily for the prevention of episodic migraine headaches. 1, 2, 3

Evidence-Based Dosing Recommendation

• The U.S. Department of Veterans Affairs and U.S. Department of Defense (VA/DoD) clinical practice guideline strongly recommends candesartan for the prevention of episodic migraine 1
• The standard effective dose used in clinical trials is 16 mg once daily 2, 3
• Candesartan has demonstrated significant reduction in migraine days compared to placebo at this dose 2
• The American College of Physicians also recognizes candesartan as an effective preventive treatment for episodic migraine 1

Clinical Efficacy

• In randomized controlled trials, candesartan 16 mg daily reduced the mean number of days with headache from 18.5 to 13.6 days over a 12-week period (p=0.001) 2
• Candesartan 16 mg showed comparable efficacy to propranolol 160 mg in a head-to-head trial, with both being superior to placebo 3
• The number of responders (patients with ≥50% reduction in migraine days) was 31.6% for candesartan compared to placebo 2
• Candesartan has shown efficacy in both episodic and chronic migraine patterns 3

Treatment Algorithm

1. Start with candesartan 16 mg once daily 1, 2
2. Continue treatment for at least 12 weeks to properly assess efficacy 2, 3
3. Evaluate response based on reduction in headache days and severity 2
4. If effective, maintain the 16 mg daily dose for ongoing prevention 3

Advantages of Candesartan

• Candesartan has a favorable side effect profile compared to many other migraine preventive medications 2, 3
• It can be particularly beneficial for patients with comorbid hypertension 4
• The VA/DoD guidelines give candesartan a "strong for" recommendation, indicating high confidence in its efficacy 1
• Tolerability is comparable to placebo in clinical trials 2

Common Side Effects and Monitoring

• Most common side effects include headache, upper respiratory tract infection, back pain, and dizziness 5
• The incidence of adverse events is similar to placebo in most studies 2, 5
• No significant dose adjustments are needed for elderly patients or those with mild to moderate renal impairment 5

Clinical Pearls and Pitfalls

• Efficacy of preventive therapy is rarely observed immediately; patients should continue treatment for at least 12 weeks before determining effectiveness 1, 2
• Abandoning treatment early due to perceived inefficacy is a common pitfall; encourage patients to maintain the full treatment course 1
• Candesartan should be considered as a first-line option for migraine prevention, especially in patients with comorbid hypertension 1, 4
• The full therapeutic effect may take several weeks to develop, so patient education about realistic expectations is important 1