Treatment algorithm

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

ACUTE

asymptomatic (marginal deficiency)

1st line – low-dose nicotinamide

Back
ACUTE
|
asymptomatic (marginal deficiency)
1st line – 

low-dose nicotinamide

Marginal deficiency exists where dietary history is indicative of a diet marginally and chronically deficient in niacin, without the development of signs and symptoms. Marginal deficiency is suggested by a dietary history indicating that food sources rich in niacin (vitamin B3), riboflavin (vitamin B2), and pyridoxine (vitamin B6) are not frequently eaten. Dietary deficiency may result from the consumption of a corn-based, low-protein diet; or a vegan diet (no animal products) with few niacin and/or tryptophan sources. It may also occur in very poor, homeless, or displaced people; those with an eating disorder (e.g., anorexia nervosa, bulimia nervosa); and those with chronic alcohol use disorder.

The development of pellagra in at-risk, asymptomatic patients of all ages can be prevented with low-dose niacin replacement therapy in the form of nicotinamide (niacinamide).[9] Nicotinamide (niacinamide) is preferred as large doses of nicotinic acid (niacin) cause nausea and vomiting and flushing of the skin, as well as numbness and tingling of the tongue and lower jaw.[9][46]​​

Primary options

nicotinamide: 15-20 mg orally once daily

symptomatic (pellagra)

1st line – nicotinamide + other B vitamins

Back
ACUTE
|
symptomatic (pellagra)
1st line – 

nicotinamide + other B vitamins

Diagnosis of vitamin B3 deficiency in symptomatic patients can be confirmed with a therapeutic trial of niacin, in the form of nicotinamide (niacinamide) 3 times daily for 5 days. In the presence of vitamin B3 deficiency, improvement in cutaneous symptoms and many neurological symptoms usually occurs within 48 hours of treatment.[8] If there is clinical improvement, therapy should be continued for 3 to 4 weeks at a dose appropriate to the severity of the presenting clinical features.[2]​​[9][19][43][50][65][90][91][92]

Nicotinic acid (niacin) replacement therapy should be administered in a multivitamin supplement preparation to ensure that other related vitamins, such as riboflavin (vitamin B2) and pyridoxine (vitamin B6), are also provided.[43]

Nicotinamide (niacinamide) is preferred, as large doses of nicotinic acid (niacin) cause nausea and vomiting and flushing of the skin, as well as numbness and tingling of the tongue and lower jaw.[9][46]​ Although a timed-release preparation of niacin is also available, it is not a recommended treatment due to its associated higher risks of side effects. Generally, the incidences of hepatic and gastrointestinal side effects have been significantly greater with use of timed-release niacin when compared to an immediate-release form.

Primary options

nicotinamide: 100-250 mg orally three times daily for 5 days, followed by 50-300 mg/day

and

multivitamin: one tablet daily

back arrow

Choose a patient group to see our recommendations

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups. See disclaimer

Use of this content is subject to our disclaimer