NAD+
A coenzyme every cell uses to make energy, now sold as injections and nasal sprays. It may be compounded; the human evidence for giving it directly is two small infusion studies.
- U.S. status
- Legal to compound
- Nicotinamide Adenine Dinucleotide (NAD) is in 503A Category 1 (bulk drug substances under evaluation), covered by FDA's interim compounding policy (list updated May 14, 2026).
- FDA source, read September 2026.
- Evidence cited here
- Longevity: Early human dataOnly uncontrolled or dosing studies in people are cited here for longevity (2 studies), with no comparison group.
- Yoo 2026 and Dollerup 2018 (40 people) did not measure longevity, so they count toward no label here. They are still listed with the studies below.
- Forms sold
- Injection · Oral · Sublingual · Nasal spray · Topical
1. What NAD+ is
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every cell, where it carries electrons in the reactions that turn food into usable energy. Sellers market extra NAD+ for energy and healthy aging.
NAD+ sits in the FDA's 503A Category 1, the list of bulk substances pharmacies may compound while the agency evaluates them. That makes compounded NAD+ legal to prescribe; it does not mean the FDA has found it effective for anything.
2. How it works
Inside the cell, NAD+ is used and recycled constantly, and it also feeds enzymes involved in DNA repair and cell signaling, which is where the longevity interest comes from. The open question is delivery: NAD+ is a large, charged molecule, and whether an injected or sprayed dose reaches the inside of cells intact, rather than being broken down first, is not settled.
The one human infusion study below found that NAD+ disappeared from the blood almost as fast as it went in for the first two hours, which fits the view that the body clears or breaks it down quickly. What that means for an injection under the skin has not been measured in people.
3. What the studies measured
A pilot study gave 11 healthy men a six-hour intravenous infusion of NAD+ or saline. Plasma NAD+ did not change for the first two hours; NAD+ and a breakdown product then rose in the urine. The study measured blood and urine chemistry only, not energy, aging or any symptom.
A review of records from one wellness clinic compared 6 clients given intravenous NAD+ with 8 given nicotinamide riboside. The NAD+ group reported moderate to severe stomach symptoms, a faster heart rate and chest pressure during infusions, which stretched infusions to 97 minutes on average. All the authors worked for the clinic that sells the infusions.
4. What they did not measure
No published study has measured NAD+ injected under the skin or sprayed into the nose in people. The only nasal NAD+ study found was in mice.
Oral precursors such as nicotinamide riboside are a different molecule. They do raise NAD+ metabolism in people, but in a 12-week trial in 40 men with obesity they did not improve insulin sensitivity or body composition, and that result says nothing direct about NAD+ injections.
The studies behind this page
The evidence label above is computed from these papers: their design and how many people they enrolled.
- Pharmacokinetic study
11 people
Counts toward: Longevity
Plasma NAD+ did not change for the first 2 hours; urinary NAD+ and methylnicotinamide rose by 6 hours. No clinical outcome was measured.
Healthy men aged 30 to 55; one 6-hour intravenous infusion of NAD+ (8) or saline (3).
Grant R, Berg J, Mestayer R, Braidy N, Bennett J, Broom S, Watson J (2019). A Pilot Study Investigating Changes in the Human Plasma and Urine NAD+ Metabolome During a 6 Hour Intravenous Infusion of NAD. Front Aging Neurosci. PMID 31572171
- Record review
14 people
Counts toward: Longevity
NAD+ infusions caused moderate to severe stomach symptoms, faster heart rate and chest pressure, and took 97 minutes on average against 37.
Clients of one wellness clinic; 500 mg intravenous NAD+ (6) or nicotinamide riboside (8) on 4 consecutive days.
Reyna K, Heinzen G, Patel N, Ritter M, Siojo A, Legere H, Pojednic R (2026). Intravenous infusion of nicotinamide adenine dinucleotide (NAD(+)) versus nicotinamide riboside (NR): a retrospective tolerability pilot study in a real-world setting. Front Aging. PMID 41704678
- Animal study
No human participants
Counts toward no label
Intranasal NAD improved smell function and repaired the olfactory lining in mice.
Mice with chemically induced loss of smell, plus cultured human olfactory stem cells.
Yoo SH, Jang JY, Bae JS, Ventura R, Kim EH, Kim AY, et al. (2026). Therapeutic effect of intranasal nicotinamide adenine dinucleotide in the restoration of olfactory dysfunction. Exp Mol Med. PMID 42380286
- Randomized trial
40 people
Counts toward no label
No improvement in insulin sensitivity, energy expenditure or body composition. This is a precursor and moves no NAD+ label.
Men with obesity aged 40 to 70; oral nicotinamide riboside (a precursor, not NAD+) 2,000 mg a day or placebo for 12 weeks.
Dollerup OL, Christensen B, Svart M, Schmidt MS, Sulek K, Ringgaard S, et al. (2018). A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects. Am J Clin Nutr. PMID 29992272
Read further
NAD+
Frequently asked questions
- Do NAD+ injections raise NAD+ in the body?
- Nobody has measured that for injections under the skin. In the one intravenous study, plasma NAD+ did not rise for the first two hours of the infusion.
- Is NAD+ legal to compound?
- Yes. NAD is in the FDA's 503A Category 1, which covers substances pharmacies may compound while FDA evaluates them. That is a regulatory status, not a finding that it works.