The mg NE measure is used because your body can also make niacin from tryptophan, an amino acid in proteins. For example, when you eat turkey, which is high in tryptophan, some of this amino acid is converted to niacin in your liver. Using mg NE accounts for both the niacin you consume and the niacin your body makes from tryptophan. Infants in their first six months do not make much niacin from tryptophan. Niacin is found naturally in many foods, and is added to some foods.
You can get recommended amounts of niacin by eating a variety of foods, including the following:. It is also available in B-complex dietary supplements and supplements containing only niacin. The two main forms of niacin in dietary supplements are nicotinic acid and nicotinamide.
Niacin in the form of nicotinic acid is also available as a prescription medicine used to treat high blood cholesterol levels. Most people in the United States get enough niacin from the foods they eat. Niacin deficiency is very rare in the United States. However, some people are more likely than others to have trouble getting enough niacin:. You can develop niacin deficiency if you don't get enough niacin or tryptophan from the foods you eat.
Severe niacin deficiency leads to a disease called pellagra. Pellagra, which is uncommon in developed countries, can have these effects:. Scientists are studying niacin to better understand how it affects health. Although niacin induced hepatotoxicity can lead to decreased clearance of lactic acid and subsequent lactic acidosis, our patient only had mildly elevated liver enzymes and prothrombin time with no signs of liver failure or coagulopathy.
Niacin is also documented to cause insulin resistance leading to hyperglycemia. However, our patient presented with hypoglycemia requiring IV dextrose infusion. Niacin causes hypoglycemia by inhibition of lipolysis and decreased production of free fatty acids which cannot be used as substrate for gluconeogenesis during prolonged fasting and starvation. Similar clinical scenarios were reported by Mittal et al. Niacin overdose has been classically associated with flushing and hepatotoxicity but in recent years, we have seen various other cases of niacin toxicity such as hypoglycemia and lactic acidosis.
These rare cases are likely to become more prevalent due to unregulated Internet-based health practices. As healthcare providers, we need to be more cautious while treating our patients.
This case, while being a unique presentation of niacin toxicity also invites us to consider other significant aspects. First, this case is a perfect example of the extensive role Internet nowadays plays in self-practiced healthcare especially by young adult population due to its uninhibited use. Second, lack of FDA regulations on nutritional and herbal supplements is quite concerning. As healthcare providers, we should be aware of the fact that our patients may be exposed to unreliable medical information leading to use of unrestricted drug paraphernalia resulting in increased incidence of various overdoses such as niacin with a myriad of clinical presentations.
We should, therefore, maintain a high degree of suspicion and should strive to keep ourselves updated about recent Internet-based health trends which are not scientifically proven but might be widely practiced by our patients.
National Center for Biotechnology Information , U. Published online Apr Beenish Fayyaz , a Hafiz J. Rehman , b and Sunita Upreti b. Hafiz J. Author information Article notes Copyright and License information Disclaimer. Received Dec 19; Accepted Feb 6. Introduction Niacin, a water-soluble vitamin, is used by physicians for treating dyslipidemias and pellagra caused by niacin deficiency. Table 1. Reported cases of niacin overdose in attempts to pass drug tests.
Source Clinical features Ingested dose Outcome Paopairochanakorn et al. Metabolic acidosis, hepatotoxicity Not reported Recovered Metabolic acidosis, hepatotoxicity, coagulopathy Not reported Recovered Mittal et al. Diabetic ketoacidosis, hepatotoxicity, prolonged QT interval.
Metabolic acidosis, hypoglycemia, myopathy. Acute renal failure, haemolytic anaemia, thrombocytopenia. Acute Liver Failure. Not reported Recovered Sheila et al. Open in a separate window. Table 2. For people with diabetes: Niacin can increase your blood sugar levels. If your blood sugar is too high, your doctor may change your dosage of niacin or take you off of the medication. For people with gout: Niacin can increase your uric acid levels, which may worsen your gout.
Your doctor may take you off of niacin if your gout worsens while taking the drug. This drug can increase the amount of acid in your stomach. This may aggravate your ulcer. For pregnant women: Niacin is a category C pregnancy drug. This means two things:. This drug should only be used if the potential benefit justifies the potential risk to your pregnancy.
For women who are breastfeeding: Niacin passes into breast milk and may cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication. For seniors: Older adults may process drugs more slowly.
A normal adult dose may cause levels of the drug to be higher than normal. All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:. The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly.
As a result, more of a drug stays in your body for a longer time. This increases your risk of side effects. Your doctor may start you on a lowered dose or a different medication schedule.
This can help keep levels of this drug from building up too much in your body. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. Always speak with your doctor or pharmacist about dosages that are right for you. High cholesterol levels put you at a higher risk for heart attack and stroke. For this drug to work well, a certain amount needs to be in your body at all times.
If you take too much: You could have dangerous levels of the drug in your body. You may have the following symptoms:. If your symptoms are severe, call or go to the nearest emergency room right away. What to do if you miss a dose: Take your dose as soon as you remember. But if you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This content does not have an Arabic version.
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Please try again. Something went wrong on our side, please try again. Show references Shi H, et al. NAD deficiency, congenital malformations and niacin supplementation. New England Journal of Medicine.
Schandelmaier S, et al. Niacin for primary and secondary prevention of cardiovascular events. Cochrane Database of Systematic Reviews.
Accessed Aug. Micromedex 2. Niacin B3; nicotinic acid oral.
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