Calcium Channel Blockers or Calcium Antagonists are used to treat a variety of conditions like hypertension, migraines and Raynaud’s disease. Calcium channel blockers prevent calcium from entering walls of the heart and blood vessel walls, resulting in lower blood pressure, they relax and widen blood vessels by affecting the muscle cells in the arterial walls.
Calcium channel blockers also appear to block the effect of the chemical serotonin that functions within nerves. Serotonin leads to narrowing, compression of the blood vessels in the head and also take down an individual’s tolerance for pain. Therefore, calcium channel blockers are believed to help prevent migraines by interrupting the action of serotonin.
These are considered a second-line treatment for migraine aversion, meaning they aren’t doctor’s first choice. Beta blockers and antidepressants are frequently viewed as the first alternative. Some patients find the number of migraine attacks increase when they first begin using calcium channel blockers to prevent migraines.
Calcium channel blockers are not approved by FDA for the treatment of migraines. Verapamil is predominantly effective in treating familial hemiplegic migraine, Flunarizine has the most evidence of being effective in treating migraines, Nimodipine, Nifedipine, Cyclandelate, and Nicardipine is other types of drugs in this category. They are useful for Basilar-type migraine and isolated aura symptoms and are considered somewhat less effective than Tricyclic antidepressants (amitriptyline), Topiramate (Topamax) and Divalproex sodium (Depakote), but multiple studies have shown that it is safe, well-tolerated and effective medicine in controlling migraine symptoms. Most dosages start from 40 mg daily and slowly increased by 40 mg each week until in the range of 240-480 mg per day.
Some calcium channel blockers are not to be taken along with grapefruits or grapefruit juice. Grapefruits reduce the liver’s ability to eliminate the drug from your system, which could cause a dangerous accumulation of the medication in your body. Precise caution should be exercised if patients are simultaneously taking other anti-hypertensive drugs, including beta blockers. Again, calcium channel blockers should be used with restraint in patients with congestive heart failure because of their tendency to “slow down” the heart muscle.
Calcium Channel blockers mechanism explained:
Side effects of calcium channel blockers:
- Constipation
- Headache
- Low blood pressure
- Rapid heartbeat (tachycardia)
- Dizziness
- Rash
- Fatigue
- Flushing
- Nausea
- Swelling in the feet and lower legs