How does oral NAD+ compare with NAD+ injections?

NAD+ is not a peptide

NAD+ is a coenzyme built from two nucleotides, not a chain of amino acids. It is covered here because it is sold beside peptides, in the same vials, capsules and sprays, and is searched for in the same way.

What the oral trial measured

The 2026 trial randomized 60 healthy adults aged 45 to 75 to a formulated oral NAD+ product or placebo for 5 days. Whole-blood (intracellular) NAD rose 53% against placebo by day 6, plasma NAD did not change, and breakdown products of NAD rose sharply. Several authors list an affiliation with the company Bryleos, and the trial was registered retrospectively.

Precursor pills

Most oral NAD+ products are precursors rather than NAD+ itself. A 2018 crossover trial found that 6 weeks of nicotinamide riboside raised NAD+ in middle-aged and older adults. A 2026 crossover in 14 men compared sublingual with oral NMN and found no significant difference in blood NMN, nicotinamide or NAD+ between the two, though some breakdown products were higher after the sublingual dose.

What the injected-NAD+ trial used

The randomized NAD+ trial cited on its profile gave 180 adults with heart failure intravenous NAD+ at 10 mg a day for 7 days, against placebo. That is an infusion study, and its findings do not transfer to a pill, a lozenge or a spray.

For what is reported about NAD+'s adverse effects at these doses, see NAD+ side effects.

Nasal NAD+

No human study of NAD+ given into the nose was found for this page. On October 7, 2026, Prof. Peptide counted NAD+ spray products at 13 of the 71 vendor catalogs it could read, which makes nasal NAD+ one of the most widely listed non-injectable products with no study behind its route.