The safety of over-the-counter niacin. A randomized placebo-controlled trial [ISRCTN18054903]

Abstract

Background: Niacin is widely available over the counter (OTC). We sought to determine the safety of 500 mg immediate release niacin, when healthy individuals use them as directed.

Effects of a niacin receptor partial agonist, MK-0354, on plasma free fatty acids, lipids, and cutaneous flushing in humans

“…A previously validated Flushing Symptom Questionnaire 19 was completed daily at 8 to 12 hours postdose during the second week of the placebo run-in period (days Ϫ7 to Ϫ1), the first 7 days of active treatment (days 1 to 7), and the last 7 days of active treatment (days 22 to 28). One of the Flushing Symptom Questionnaire questions assessed the intensity of all four flushing symptoms (skin redness, warmth, tingling, and/or itching) in aggregate using an 11-point numerical rating scale, the Global Flushing Severity Score (GFSS), which was labeled with the following intensity categories: none (score of 0), mild (1-3), moderate (4 -6), severe (7)(8)(9), and extreme (10).…”

“…7 Flushing of the face, neck, and trunk occurs in most patients (Ͼ90%) receiving niacin therapy. 8 These adverse cutaneous reactions limit patient acceptance and have precluded widespread use of niacin.…”

Flushing Profile of Extended-Release Niacin/Laropiprant at Initiation of Therapy in Asian Lipid Clinic Patients

“…Doses of at least 1 g/day are required to produce beneficial lipid-modifying effects; a dose of 2 g provides twice the low-density lipoprotein cholesterol reduction and high-density lipoprotein cholesterol elevation and a several-fold additional reduction in triglycerides. Despite these benefits, niacin is underutilized in clinical practice due to flushing, which occurs in over 90% of niacin-treated patients [6,7,8,9,10,11,12]. Measures to mitigate flushing, such as pretreatment with aspirin, have been largely unsuccessful, as evidenced by the frequent failure to attain an optimal therapeutic niacin dose and the high rate of discontinuation of niacin therapy [13].…”

Lipid-modifying efficacy of extended release niacin/laropiprant in Asian patients with primary hypercholesterolemia or mixed hyperlipidemia

“…[5][6][7] Despite the beneficial effects on lipids, niacin is underused in clinical practice, primarily because flushing of the face and trunk, which occurs in up to 90% of niacin users. 6,[8][9][10][11] Niacininduced flushing is mediated primarily by prostaglandin D 2 (PGD 2 ), which stimulates PGD 2 receptor 1 in the skin. 12 The PGD 2 -mediated flushing pathway is independent of the lipid-modifying pathway of niacin, 13 enabling the development of an agent that inhibits PGD 2 -mediated flushing without interfering with the beneficial lipid-modifying effects.…”