Yes, taking high doses -- 100 mg or more -- of niacin daily can lower your blood pressure. If you have low blood pressure, you should not take niacin because it could cause levels to drop further. If you suffer from hypertension -- high blood pressure -- do not take over-the-counter forms of niacin without talking to your doctor. Niacin may help some conditions associated with high blood pressure, but is not typically prescribed to treat hypertension.
Niacin and Blood Pressure
The American Heart Association does not include niacin on a long list of medications recommended to treat high blood pressure. Drugs more likely prescribed to treat high blood pressure include beta blockers, calcium channel blockers, ACE (angiotensin-converting enzyme) inhibitors, alpha blockers, blood vessel dialators and central agonists, a medication that helps prevent contractions in your blood vessels. Hypertension puts you at risk of cardiovascular disease. Niacin may help conditions associated with high blood pressure and heart disease such as cholesterol and atherosclerosis -- hardening of the arteries.
Risks
You can purchase niacin -- vitamin B3 -- without a prescription. But self-medicating with large amounts of niacin could prove dangerous. Niacin can cause stomach ulcers and liver damage. It can also cause an unpleasant side effect called skin flushes, a condition that makes your chest and face turn red, burn and tingle. Timed-release formulas of niacin can help prevent skin flushes, but they increase your risk of incurring liver damage. If you take other blood pressure medications such as clonidine, taking niacin could make your blood pressure drop too low.
Niacin Study
Niacin, prescribed for more than 50 years to treat cholesterol, proved disappointing in a study testing niacin's ability to prevent heart disease. The study, funded by the National Institutes of Health, involved 3,414 participants. About half of the participants took statins, a cholesterol-lowering drug, and the others took both statins and 2,000 mg of niacin daily. The combination therapy improved overall cholesterol levels better than statins alone, proving especially effective in elevating levels of high-density lipoprotein, HDL or "good" cholesterol. But persons who took niacin and statins suffered about the same number of heart attacks and more than twice as many strokes as participants who took only statins. The NIH halted the study in May 2011.
Considerations
A blood pressure test reveals your systolic blood pressure -- the top number -- and your diastolic number -- the lower number. Healthy blood pressures measures 120/80 mm Hg (millimeters of mercury). Systolic blood pressure higher than 140 or diastolic blood pressure higher than 90 signals stage 1 hypertension. Numbers that top 180 or 100 require emergency medical care. Low blood pressure may indicate dehydration, infection or disease. An eating plan that includes high-fiber foods such as vegetables, legumes, fruits and whole grains, lean protein and restricted sodium can help reduce your blood pressure.
References
- University of Maryland Medical Center; Vitamin B 3 (Niacin); June 18, 2009
- MedlinePlus: Niacin and Niacinamide (Vitamin B3)
- American Heart Association; Types of Blood Pressure Medications; May 2, 2011
- National Institutes of Health: NIH Halts Clinical Trial on Combination Cholesterol Treatment; May 26, 2011
- CBC News; Niacin Trial For Heart Disease Stopped Early; May 27, 2011
- University of Maryland Medical Center; Blood Pressure; David C. Dugdale, III, M.D.; May 2, 2009
