If you purchase niacin, also known as vitamin B-3, in capsule form from a drugstore, it likely contains niacinamide. Your doctor may prescribe either niacin or niacinamide, depending on your medical condition. Niacin and niacinamide provide different benefits but present similar side effects. Both niacin and niacinamide may lower your blood pressure.
Niacin vs. Niacinamide
It may prove important to your health to know the differences between niacin and niacinamide, as well as the effect of each on your blood pressure. Niacin, in high doses, can lower your cholesterol and reduce hardening of the arteries. Niacinamide may help delay the progression of type 1 diabetes and alleviate symptoms of osteoarthritis. Slight evidence suggests that either may treat conditions such as dizziness, Alzheimer's disease and migraine headaches, but research is lacking about such uses.
Blood Pressure
People with low blood pressure should not take any type of vitamin B capsule, as doing so could exacerbate the problem. You should also not take niacin to treat hypertension -- high blood pressure -- without a doctor's approval and advice about the proper dose. Taking too much niacin could drastically reduce your blood pressure -- your heart could stop. Niacin may also interfere with other medications, including statins, a type of cholesterol-lowering drug; diabetes-controlling medications; and some blood pressure drugs.
Side Effects
If you take vitamin B-3 in high doses -- more than 100 mg a day -- you put yourself at risk for serious side effects that include vision loss, gout, stomach ulcers and liver damage. Niacin can cause dangerously high blood sugar elevations in people with type 2 diabetes and may accelerate kidney disease. The National Institutes of Health halted a niacin study in May 2011, 18 months earlier than planned, after persons who took 2,000 mg a day suffered twice as many strokes as study participants who did not take niacin.
Considerations
If you believe niacin or niacinamide may help treat a B-3 deficiency or improve a medical condition, talk to your doctor. The side effects of B-3 could seriously compromise your health. If you've unintentionally lowered your blood pressure by taking vitamin B-3 capsules, ask a health care professional whether it would prove prudent to lower your dose or stop taking vitamin B-3. If you want to lower your blood pressure, other medications are available. Lifestyle and home remedies may also help, including lowering the amount of sodium and raising the amount of potassium in your diet, and exercising regularly.
References
- University of Maryland Medical Center; Vitamin B-3 (Niacin); June 2009
- Medline Plus; Niacin and Niacinamide (Vitamin B3); April 2011
- National Institutes of Health; NIH Halts Clinical Trial on Combination Cholesterol Treatment; May 2011
- CBC News; Niacin Trial for Heart Disease Stopped Early; May 2011
- American Heart Association; Prevention and Treatment of High Blood Pressure; May 2011
