NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every cell. It is not a peptide, but it is sold through the same clinics and telehealth services, as intravenous drips and as small injections under the skin or into muscle. The benefits advertised — more energy, slower ageing, sharper focus, easier withdrawal from alcohol or drugs — are a list of claims. This page sets each one beside what has actually been measured in people who received NAD+ by injection or infusion.
What doses trials and clinics use is on our NAD+ dosage page, what has been reported as side effects is on our NAD+ injection side effects page, and how NAD+ compares with the capsule precursor NMN is on our NAD+ vs NMN page. Nothing here is a recommendation. What clinics and telehealth services charge for it is on our NAD+ price-per-milligram page.
The short answer, from a 2026 systematic review
A PRISMA systematic review published in Ageing Research Reviews in 2026 (Gallagher and Emmanuel, PMID 41655607) searched for human and rodent intervention studies of NAD-boosting compounds from January 2010 to October 2025. It found 113: 33 in people (28 randomised) and 80 in rodents. Its finding on injections is direct: "No eligible outcomes trials evaluated intravenous or intramuscular NAD⁺ itself for anti-aging or wellness indications." The only intravenous NAD+ study it found was a pharmacokinetic pilot with no clinical outcome, which it treated as context only.
The oral precursors fared better on chemistry than on outcomes: they "consistently demonstrated biochemical target engagement" — they raise NAD-related molecules in blood — but effects on function, metabolism and blood vessels were "heterogeneous and often null." The review's conclusion was that clinical effectiveness for anti-ageing or wellness "remains inconclusive," and that larger trials were needed "particularly for parenteral approaches."
The claims, set against the record
| Claim on clinic pages | Human study of injected NAD+ | What it measured | Result |
|---|---|---|---|
| Heart and circulation | Yu et al. 2026, randomised, placebo-controlled, 180 people with heart failure | Ejection fraction at one month | 45.44% vs 42.44% (p = 0.024); readmissions not significantly different |
| Raises NAD+ levels | Grant et al. 2019, pilot in healthy adults, 6-hour infusion | Plasma and urine NAD+ metabolites | No plasma change for 2 hours; urine breakdown products up by 6 hours |
| Metabolic health | Reyna et al. 2026, clinic chart review, 500 mg × 4 days | Liver, kidney, thyroid, glucose, lipids at 30 days | No change in fasting glucose or LDL; HDL fell in the NAD+ group |
| Addiction and withdrawal | Blum et al. 2022 and 2024, 50 cases each, no control group | Self-rated craving, anxiety, depression | Scores fell; NAD+ given with other agents |
| Parkinson's disease | Birkmayer et al. 1993, open label, 885 patients, NADH IV or oral | Disability score | ~80% "beneficial"; no control group, NADH not NAD+ |
| Energy, focus, anti-ageing, skin, athletic recovery | None | — | — |
Sources: PMID 40954388, 31572171, 41704678, 36118157, 39949994, 8101414, all read 15 October 2026.
Heart failure: the one controlled result
The only randomised, placebo-controlled trial of injected NAD+ with a clinical outcome gave 10 mg a day intravenously for seven days to 180 adults whose heart failure came from ischaemic heart disease, on top of standard treatment. Ejection fraction — the share of blood the left ventricle pumps out with each beat — was 45.44% against 42.44% at one month. Hospital admissions for heart failure at six months (13.5% against 23.6%) and major cardiac events (14.6% against 24.7%) leaned the same way but were not statistically significant.
Two limits travel with it. It was a single-centre trial in one disease, and it used a dose fifty times smaller than the 500 mg drips sold in the US wellness market — our dosage page sets out that gap. A heart-failure result at 10 mg is not evidence for an energy drip at 500 mg.
Does an injection raise NAD+? The one measurement
Grant and colleagues infused NAD+ at 3 µmol per minute for six hours — about 716 mg in total, by our arithmetic — and sampled blood and urine throughout. For the first two hours, plasma NAD+ and its metabolites did not change; the authors concluded that NAD+ "is rapidly and completely removed from the plasma" at that rate. By six hours, urinary NAD+ and methylnicotinamide (a breakdown product) had risen.
The study measured chemistry in blood and urine, not inside cells, and not any outcome a person would notice. Two of its listed affiliations were NAD+ Research Inc. and the Springfield Wellness Center. Whether repeated drips raise NAD+ in muscle or brain — the tissues the marketing is about — has not been measured in people.
What a clinic's own records showed
In 2026 staff at a US wellness chain published a retrospective review of their own clients' records (Reyna et al., Frontiers in Aging, PMID 41704678): four consecutive days of 500 mg NAD+ by IV, or the precursor nicotinamide riboside by IV, with 30 days of follow-up. NAD+ drips caused moderate to severe stomach symptoms, a faster heart rate and chest pressure during the infusion, and took 97 minutes on average against 37 for the precursor. Liver enzymes, CRP, kidney and thyroid tests did not change. HDL cholesterol fell in the NAD+ group; HbA1c fell in the precursor group; fasting glucose and LDL did not change in either. All authors were employed by the chain. It was not designed to test a benefit, and it found none it could attribute to NAD+.
How the drip compares with the oral route is on our NAD+ injection vs oral page.
Addiction: the oldest claim, the weakest design
The idea is old: a 1961 "preliminary report" proposed diphosphopyridine nucleotide — NAD+'s former name — for treating drug addiction (O'Hollaren, PMID 13730082). The modern published record is two case series from the same lead author, each of 50 people at chemical-dependency programmes, who received a series of infusions combining NAD+ with an enkephalinase inhibitor, amino acids (d-phenylalanine, glycine, alanyl-glutamine) and a B-vitamin cocktail. Self-rated craving, anxiety and depression scores, collected by counsellors on 1–10 scales, fell between baseline and the end of treatment.
There was no comparison group, NAD+ was one ingredient among several, and the outcome was the patients' own rating while in a treatment programme. The 2024 paper discloses that the lead author owns patents on a related product. These reports show what happened to 100 people in programmes; they cannot show what NAD+ did.
What is registered, and what it will and will not answer
ClinicalTrials.gov, searched 15 October 2026, holds eight registrations that give NAD+ by injection or infusion. None has posted results.
| Registration | Who | Primary outcome | Status |
|---|---|---|---|
| NCT05849519 | Sudden hearing loss, China | Hearing | Unknown |
| NCT06558253 | Cord-blood transplant, China | Blood-count recovery | Recruiting |
| NCT06590844 | Liver cancer with immunotherapy, China | Tumour response | Unknown |
| NCT06776510 | Immune thrombocytopenia, China | Platelet response | Recruiting |
| NCT07328100 | Vascular ageing, China | Flow-mediated dilation | Not yet recruiting |
| NCT07839130 | Children with heart dysfunction, China | Ejection fraction | Not yet recruiting |
| NCT06382688 | Healthy adults, US | IV NAD+ vs IV nicotinamide riboside | Unknown |
| NCT06919328 | Healthy adults, US | Injection pain and discomfort | Recruiting |
The Chinese trials test a hospital product, Coenzyme I for Injection, in specific diseases. The two US registrations compare tolerability. None measures energy, cognition, mood, skin or ageing in healthy adults — the outcomes the drip market sells. The vascular-ageing trial is the nearest; it is a seven-day infusion against saline, and it had not started.
What the record does not contain
- An outcome trial of injected or infused NAD+ for energy, fatigue, cognition, longevity, skin or athletic recovery.
- Any trial at the 250–1,000 mg doses US clinics sell that measured a benefit.
- A controlled trial in addiction.
- A measurement of NAD+ inside human muscle or brain after injection.
- Any approved injectable NAD+ product in the United States; FDA's findings on compounded vials are on our side effects page.
A plain explainer of the molecule is Peptide Lexicon's NAD+ entry. For how the other products in this market measure up against their own trials, see our peptides before and after page.
Sources and dates
Read 15 October 2026: abstracts of PMIDs 41655607, 40954388, 31572171, 41704678, 39949994, 36118157 and 8101414, and the PubMed record for PMID 13730082; ClinicalTrials.gov records NCT05849519, NCT06558253, NCT06590844, NCT06776510, NCT07328100, NCT07839130, NCT06382688 and NCT06919328 (search of interventions naming NAD+, nicotinamide adenine dinucleotide, coenzyme I or NADH, filtered to injection or infusion).