Hyperglycemia niacin

The major adverse effect of niacin treatment is intense cutaneous flushing (vasodilation), which manifests as an uncomfortable burning sensation and itchiness of the face and upper body, thereby limiting patient compliance to therapy [13]. Moreover, a short half-life, dyspepsia, hyperuricemia, and modest hyperglycemia were also reported [14-16]. 

Acipimox (5) was introduced in Europe to treat hyperlipidemia in 1985 [47,48]. Acipimox is a weak agonist of GPR109A with micromolar binding and functional activity. Like niacin, acipimox raises HDL-C and triggers vasodilation in humans. However, it remains unclear whether acipimox causes mild hyperglycemia as is observed with niacin [49,50]. 

Potentially important laboratory abnormalities occurring with niacin therapy include elevated liver function tests, hyperuricemia, and hyperglycemia. Niacin-associated hepatitis is more common with sustained-release preparations, and their use should be restricted to patients intolerant of regular-release products. Niacin is contraindicated in patients with active liver disease, and it may exacerbate preexisting gout and diabetes. 

Nicotinic acid (niacin) Yes Reduces LDL Reduces VLDL Raises HDL IV Ik with fibrates severe IV with fibrates Cutaneous flush, GI distress, liver dysfunction, hyperglycemia, hyperuricemia... 

Schwartz ML. Severe reversible hyperglycemia as a consequence of niacin therapy. Arch Intern Med... 

Chronic megadoses of niacin may be associated with hyperglycemia, hyperuricemia, cardiac arrhythmias, hepatotoxicity, cystoid maculopathy, myopathy, peptic ulcers, and hyperkeratotic pigmented skin lesions. These problems may occur with doses exceeding 3gday. ... 

The most common serious side effects are hepatotoxicity, manifested as elevated serum transaminases and hyperglycemia Both regular (crystalline) niacin and sustained-release niacin have been reported to cause severe liver toxicity, and sustained-release niacin can cause fulminant hepatic failure. An extended-release niacin (NIASPAN), appears to be less likely to cause severe hepatotoxicity, perhaps because it is administered only once daily. The incidence of flushing and pruritus with this preparation is not substantially different from that with regular niacin. Severe hepatotoxicity is more likely to occur when patients take >2 g of sustained-release, over-the-counter preparations. Affected patients experience flu-like fatigue and weakness. Usually, serum transaminases are elevated serum albumin levels decline, and total cholesterol and LDL-C levels decline substantially. 

In patients with diabetes mellitus, niacin should be used cautiously, since niacin-induced insulin resistance can cause severe hyperglycemia. Niacin use in patients with diabetes mellitus often mandates a change to insulin therapy. If niacin is prescribed for patients with known or suspected diabetes, blood glucose levels should be monitored at least weekly until proven to be stable. Niacin also elevates uric acid levels a history of gout is a relative contraindication for niacin use. Rarer reversible side effects include toxic amblyopia and toxic maculopathy. Atrial tachyarrhythmias and atrial fibrillation have been reported, more commonly in elderly patients. Niacin, at doses used in humans, has been associated with birth defects in animal models and should not be taken by pregnant women. 

Efficacy and safety studies with ER niacin have shown benefit, albeit with some safety concerns that were reported many years ago with nicotinic acid, such as small increased risks of hyperglycemia and hyperuricemia. 

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