What is it?
Vitamin B3 amide
1Niacinamide (nicotinamide) is the amide form of vitamin B3. It is one of the common supplemental forms of niacin and is distinct from nicotinic acid, nicotinamide riboside, NMN, and NAD+ products.
Human cognitive evidence is limited and indirect
8In a secondary analysis of 310 adults participating in a skin-cancer prevention trial, 500 mg nicotinamide twice daily did not yield a statistically significant change in measured cognitive performance or quality of life over 12 months. The study population differs from healthy people seeking a nootropic, so this result cannot demonstrate a cognitive benefit for that use.
Names, aliases and forms
Mechanisms of action
NAD-related metabolism
2Niacinamide contributes to NAD and NADP coenzymes. This biochemical role does not itself show a nootropic effect in people who already meet their niacin needs.
Potential effects and evidence map
Current clinical research does not establish a reliable nootropic effect from plain niacinamide. The available cognitive outcome data come from a non-nootropic clinical population and report null findings, so their relevance to healthy adults is uncertain.
Available human cognitive research is limited and does not establish an acute mental-energy effect from plain niacinamide in healthy adults.
A year-long clinical analysis did not show a significant memory or learning change with nicotinamide in its study population; benefit in healthy users is not established.
Direct evidence does not establish a focus benefit from plain niacinamide for healthy adults.
Typical dosages and timing
The adult RDA for total niacin is 16 mg NE/day for men and 14 mg NE/day for women. It is nutritional intake context, not a demonstrated nootropic dose for plain niacinamide. The U.S. adult UL for supplemental niacin is 35 mg/day.
Timing & effect horizon
A 2025 clinical pharmacokinetic analysis used 1,500 mg twice daily. It was not a healthy-user cognitive trial and does not establish a routine nootropic dose, schedule, or benefit.
A 500 mg twice-daily regimen appeared in a trial context unrelated to cognitive enhancement. It should not be read as a routine dose, nootropic cycle, or price-comparison target.
In a four-person study using 1-6 g oral doses, nicotinamide The time for blood levels to fall by half during the final elimination phase.Source increased with dose: about 1.5 hours at 1 g, 4 hours at 2 g, and 7-9 hours at 4-6 g. These results are high-dose pharmacokinetic context, not effect duration.
Safety, side effects and risk profile
Higher doses can cause nausea or gastrointestinal effects; nutrient-level use should not be equated with high-dose trials.
High-dose or long-term use warrants separate liver and kidney safety consideration; this is not a base-risk rating for normal nutritional intake.
Medication context is most relevant for high-dose niacin-related exposure, especially antidiabetes medicines.
Pregnancy and lactation nutrient needs are distinct from high-dose supplemental use.
NAD-related biology and non-cognitive clinical studies do not demonstrate a nootropic effect in healthy adults.
Nicotinamide does not cause the flushing typical of nicotinic acid, but nausea, vomiting, and signs of liver toxicity have been reported around 3,000 mg/day. In small dialysis studies, diarrhea and low platelet counts occurred at 500-1,500 mg/day over several months; those data do not describe nutrient-level use.
Interactions and cautions
The NIH fact sheet lists isoniazid and pyrazinamide as agents that affect niacin pathways. High-dose nicotinic acid can affect blood glucose and needs distinct consideration for people using antidiabetes medication; that evidence should not be extrapolated wholesale to standard-dose niacinamide.
Legal and regulatory status
As of 2026, FDA does not approve dietary supplements for safety and effectiveness before sale. This general U.S. framework does not mean an individual niacinamide product is approved; requirements can differ outside the United States.
How it compares
These products differ in chemical identity and label context, so dose, effect, and price comparisons should remain ingredient-specific. Niacinamide is less associated with flushing than nicotinic acid.
Practical buying and quality notes
- Offer inventory can include products named NAD+, NR, NMN, or vitamin B3. Only compare like-for-like products labelled plain niacinamide or nicotinamide; then compare amount per serving, form, price per unit, and availability.1
- For capsules, compare the amount per capsule and other B-vitamin sources. For powders, verify the label, net amount, serving measure, batch or lot identity, and accessible manufacturing or quality documentation before comparing price per gram.7
- NR, NMN, NAD+ products, nicotinic acid, and multivitamin blends are not like-for-like substitutes for plain niacinamide. Exclude them from a plain-niacinamide unit-price comparison.1
FAQ
What niacinamide dose is established for focus?
1No niacinamide dose is established for focus or other nootropic effects. The adult RDA is 14-16 mg NE/day of total niacin from all sources, not a plain-niacinamide focus target; higher clinical regimens were studied for other purposes.
How long does niacinamide take to work?
6No nootropic onset, duration, or cycle is established. High-dose pharmacokinetic studies describe blood levels and elimination, not a time to a cognitive benefit or a recommended use period.
Niacinamide versus nicotinic acid
1Both belong to the vitamin B3 family, but niacinamide does not share nicotinic acid’s typical flushing profile or its pharmacologic lipid-use evidence. High-dose safety and clinical research remain form-specific.
References
- NIH Office of Dietary Supplements. Niacin: Fact Sheet for Health Professionals.
- MacKay D, Hathcock J, Guarneri E. Niacin: chemical forms, bioavailability, and health effects. Nutr Rev. 2012.
- Rennie G, Chen AC, Dhillon H, Vardy J, Damian DL. Nicotinamide and neurocognitive function. Nutr Neurosci. 2015.
- Ketron GL, Grun F, Grill JD, et al. Pharmacokinetic and pharmacodynamic assessment of oral nicotinamide in the NEAT clinical trial for early AD. Alzheimers Res Ther. 2025.
- Chen AC, Martin AJ, Choy B, et al. A phase 3 randomized trial of oral nicotinamide in high-risk dermatology patients. N Engl J Med. 2015.
- Stratford MR, Rojas A, Hall DW, et al. Pharmacokinetics of nicotinamide and its effect on blood pressure, pulse and body temperature in normal human volunteers. Radiother Oncol. 1992.
- U.S. Food and Drug Administration. Questions and Answers on Dietary Supplements.
- Martin AJ, Dhillon HM, Vardy JL, et al. Neurocognitive Function and Quality of Life Outcomes in the ONTRAC Study for Skin Cancer Chemoprevention by Nicotinamide. Geriatrics. 2019;4(1):31.