NAD+ is nicotinamide adenine dinucleotide. It is a dinucleotide coenzyme, not a peptide. PubChem lists it at about 663 Da (CAS 53-84-9). PeptidePrices still tracks research-vendor NAD+ listings because those vials sit next to research peptides. A catalog page is not a drug label.
Injectable NAD+ is not FDA-approved for human use as a drug for anti-aging or longevity. A 2019 human pilot measured plasma and urine metabolites during a 6-hour IV infusion. That is a metabolome study. It is not a longevity trial.
The site already has a short NAD+ research profile and a beginner NAD+ guide. This explainer is the evidence map: what NAD+ is, which human studies measured NAD+ itself, what the IV numbers are, and where clinic copy outruns the papers.
What NAD+ is
NAD+ is two nucleotides joined through a pyrophosphate: nicotinamide on one side, adenine on the other. Cells cycle it between NAD+ and NADH while moving electrons through metabolism. That redox cycle is not consumed when it is only shuttling electrons. Separate enzymes consume NAD+ as a substrate: sirtuins, PARPs, and CD38-family glycohydrolases. Reviews map that biochemistry (Imai and Guarente, 2014; Katsyuba et al., 2020; Abdellatif et al., 2021). A review is context. It is not infusion efficacy.
NAD+ is in every cell. It is not a peptide, and it is not SS-31. Sharing a longevity conversation is not sharing a molecule.
| Thing | What it is | What a paper can show |
|---|---|---|
| Endogenous NAD+ | The coenzyme already inside cells | Tissue or blood concentrations, often observational |
| IV NAD+ infusion | Exogenous NAD+ dripped into a vein | Plasma and urine metabolites, infusion-time symptoms |
| Oral precursors (NMN, NR) | Molecules converted toward NAD+ | Separate oral trials. Not an IV NAD+ result |
| Research-vendor vial | A catalog chemical sold as NAD+ | Paperwork and listed milligrams, not a trial product |
A COA check can test whether a certificate names a real lab. It cannot turn a research vial into the Archway infusion used in Grant 2019.
Age-associated NAD+: tissue is not whole blood
The longevity pitch starts from a decline story. Two independent human primary papers measure NAD+ itself. They do not say the same thing. Neither is an infusion study.
Massudi et al., PLoS ONE, 2012. NAD+, oxidative-stress marks, PARP, and SIRT1 were quantified in non-sun-exposed pelvic skin from 49 surgical patients (newborns through age 77). NAD+ fell with age in males 0-77 (r = -0.769, p = 0.0007) and in post-pubescent males after newborns were dropped (r = -0.706, p = 0.0001). Post-pubescent females (36-76) also showed a negative correlation (r = -0.537, p = 0.01). In males, PARP rose with age and inversely tracked NAD+ (r = -0.638, p = 0.0003). SIRT1 fell in post-pubescent males (r = -0.612, p = 0.007) and did not in females. The authors limited the oxidative-stress / PARP / NAD+ cascade to male skin. This is discarded surgical skin. It is not whole-blood NAD+, and it is not a 50 percent decline from age 40 to 60.
Yang et al., Frontiers in Endocrinology, 2022 (PMID 35388296). Independent of Massudi. PMID 35370948 on the live research profile is a different paper. In 1,518 Jidong adults (mean age 43.0; 52.6% men), mean whole-blood NAD+ was 33.0 ± 5.5 μmol/L. Men sat higher than women (34.5 vs 31.3 μmol/L). Five age-band means were 33.33, 33.14, 32.51, 33.31, and 32.71 μmol/L from ≤29 through ≥60. Those bands did not differ in the total sample (p = 0.28). After adjustment, the 40-49 band was lower than ≤29 (β -1.12; 95% CI -2.18 to -0.06). That pooled trend did not hold after 50. Sex modified the association (p for interaction = 0.003). In men, ≥60 was lower than ≤29 (adjusted β -2.16; 95% CI -4.16 to -0.15). Women did not show a male-style decline.
| Paper | Matrix | N | What moved | What did not |
|---|---|---|---|---|
| Massudi 2012, PLoS ONE | Pelvic skin | 49 | NAD+ fell with age in both sexes. PARP and NAD+ moved together in males | A pooled 50% figure. A blood result. An infusion |
| Yang 2022, Front Endocrinol | Whole blood | 1,518 | Men higher than women. Men ≥60 lower than ≤29 after adjustment | A significant age-band difference in the total sample (p = 0.28) |
A skin correlation and a sex-specific blood coefficient do not mean an IV drip reverses aging. The centenarian immune-system roundup already treats pathway overlap as a hypothesis, not a human-longevity result.
The 2019 IV metabolome pilot
The human paper that infused NAD+ and reported timed plasma and urine metabolites is Grant, Berg, Mestayer, and colleagues in Frontiers in Aging Neuroscience (12 September 2019, PMID 31572171, DOI 10.3389/fnagi.2019.00257). NCBI title lookup matches that record. It is not Antioxidants. PMID 31508207 is unrelated.
Eleven healthy men aged 30-55 were randomized to NAD+ (n = 8) or saline (n = 3). The test arm received 750 mg NAD+ in saline over 6 hours (about 2 mg/min, stated as 3 μmol/min), plus 0.1% dextrose. Blood was drawn at 0, 30, 60, 120, 360, and 480 minutes. Urine was pooled to 30 minutes, 2 hours, 6 hours, and 8 hours. Analysis used LC/MS/MS. IRB: William Carey University protocol 2017-12. The drip ran at Springfield Wellness Center. NAD+ Research Inc. and the Australasian Research Institute funded it. Richard Mestayer is a director of NAD+ Research Inc. and medical director of the clinic that uses IV NAD+ as therapy.
At 3 μmol/min, plasma NAD+, nicotinamide, ADPR, methyl-nicotinamide, and NMN did not rise for the first 2 hours. At 6 hours, plasma NAD+ was 398% above baseline (p < 0.0001 vs baseline; p < 0.001 vs 6-hour saline). Nicotinamide rose 409%, ADPR 393%, and methyl-nicotinamide 350%. NMN was 472% above baseline only at 8 hours. Urinary NAD+ excretion was 538% higher at 6 hours than at 30 minutes. Urinary methyl-nicotinamide rose 403%. Urinary nicotinamide did not rise. The authors read the NAM/ADPR pair (Spearman r = 1.00) as glycohydrolase activity, and the 2-hour flat line as complete removal from plasma into tissue, extracellular metabolism, or both. They calculated 1,080 μmol infused by 6 hours. If that load had stayed in about 5 L of blood, plasma would have risen about 18 μM every 30 minutes. It did not, until after 2 hours.
Those percentages are plasma and urine changes in eight infused men. They are not brain NAD+, not a cognition score, and not a lifespan result. The discussion still mentioned Alzheimer's and "NAD+ based treatment regimens."
The same paper reported no observed adverse events during the 6-hour infusion. Liver-function shifts at 8 hours (GGT, LD, AST down; bilirubin up 2.75 μmol/L) were statistically detectable and judged not clinically significant. That safety sentence applies to this rate, this dose, these 11 men, and this 8-hour window.
Research and clinic study exposures
Injectable NAD+ is not approved for human use as an anti-aging or longevity drug. The table reports study exposures. It is not a dosage guide and it is not a consumer protocol.
| Setting | Reported exposure | Source |
|---|---|---|
| IV metabolome pilot, healthy men | 750 mg NAD+ in saline over 6 hours (about 2 mg/min, 3 μmol/min) | Grant et al., 2019 |
| IV NR vs NAD+ tolerability preprint | 500 mg NAD+ IV or 500 mg NR IV in 500 mL saline; rate titrated to comfort | Hawkins et al., 2024 medRxiv preprint |
That does not make 750 mg, 500 mg, 2 mg/min, or 3 μmol/min an approved dose. Grant et al. wrote that 750 mg over 6 hours "reflects a common dosing regimen in clinics" and named Springfield Wellness Clinic. That is a description of what that clinic was already doing. It is not a protocol, and it is not FDA labeling.
A later randomized pilot, posted as a medRxiv preprint on 10 June 2024 (Hawkins et al.; NCT06382688), used 500 mg NAD+ IV against 500 mg NR IV, oral NR, and saline. Study 1 randomized 37 people (NAD+ IV n = 10; NR IV n = 11; saline n = 6; oral NR n = 10). Mean chair time was 182.9 ± 55.93 minutes for NAD+ IV, 127.2 ± 40.82 minutes for NR IV, and 85.17 ± 9.745 minutes for saline. Study 2 (n = 8 per IV arm) started with the line fully open. The preprint is not peer-reviewed. ChromaDex funded it and employs several authors.
Acute infusion reactions
Grant 2019, at about 2 mg/min for 6 hours, reported no observed adverse events. That is the measured sentence for that protocol.
Faster or comfort-titrated NAD+ IV is a different exposure. Hawkins et al. wrote that clinician- and participant-reported experiences include nausea, diarrhea, muscle cramping, chest pains, and dizziness. Participant comments include chest tightness, nausea, flushing, and cramping that eased when the rate slowed or the infusion ended. Those are infusion-time symptoms in a small, industry-funded preprint. They are not a labeled adverse-reaction table, and they are not proof of cardiac injury.
Clinic practice of running NAD+ slowly is a description of how operators respond to those symptoms. It is not medical advice, and it is not a rate to copy from this page.
What this does not mean
- It is not human longevity efficacy. No cited trial gave IV NAD+ and measured lifespan or a controlled anti-aging clinical outcome.
- It is not FDA approval. Injectable NAD+ is not approved for anti-aging, longevity, addiction, Parkinson's disease, or chronic disease on the evidence used here.
- A 398% plasma rise is not tissue repletion. Grant et al. did not sample muscle, brain, or skin. The first 2 hours were a plasma flat line.
- Skin NAD+ falling with age is not a blood collapse. Massudi is surgical skin. Yang's total-sample age bands did not differ (p = 0.28).
- Oral NMN or NR trials are not IV NAD+ trials. They are a different route and a different molecule at the point of swallowing.
- Addiction, Parkinson's, and clinic "energy" claims are not established here. Grant cited older addiction-clinic literature as background. That is not a modern controlled efficacy trial in this source set.
- A research-vendor vial is not the study infusion. Identity, salt, sterility, and amount can differ.
- This is not medical advice, and it is not a consumer dosing protocol.
Limitations
Grant 2019 used eight infused men and three saline controls, aged 30-55, BMI under 30, on a niacin-reduced diet. There is no women-in-the-infusion-arm result.
The paper measured plasma and urine metabolites plus a short liver-enzyme panel. There is no intracellular NAD+ map, no cognitive or functional endpoint, and no follow-up past 8 hours.
Hawkins 2024 adds a second NAD+ IV exposure and more symptom language. It is a preprint, ChromaDex-sponsored, and built to compare NR IV with NAD+ IV.
Age data disagree by compartment and sex. Massudi's skin correlations are real and small-N. Yang's blood study is large and mostly flat, with a male ≥60 signal after adjustment. Whole blood is not pelvic skin.
Compounded or research-chemical NAD+ is not an approved finished drug for longevity.
What to watch
- A controlled IV NAD+ trial with a clinical endpoint. Metabolome percentages are not that trial.
- Peer-reviewed publication of NCT06382688, or an independent replication. Until then Hawkins stays a preprint.
- Tissue-specific human NAD+ series that name the matrix. Blood, skin, muscle, and brain are different measurements.
- Whether later IV papers keep the 6-hour, 750 mg motif. Hawkins used 500 mg and a shorter, comfort-titrated chair time.
- Sex-stratified analyses. Yang shows why pooled blood curves can hide a male-only band. Grant enrolled men only.
FAQs
Is NAD+ a peptide?
No. It is a dinucleotide coenzyme (about 663 Da, CAS 53-84-9). PeptidePrices lists it because research vendors sell it next to peptides.
Did IV NAD+ reverse aging in people?
No. Grant 2019 measured plasma and urine metabolites during a 6-hour infusion. Metabolome change is not a longevity result.
What dose was used in the human IV paper?
Grant et al. reported 750 mg over 6 hours (about 2 mg/min) in eight men. Injectable NAD+ is not approved for human use as an anti-aging or longevity drug. That does not make 750 mg an approved dose or a consumer protocol.
Why do some clinics run the drip slowly?
Grant's 6-hour, 3 μmol/min infusion reported no observed adverse events. A 2024 preprint (Hawkins et al.) recorded chest tightness, nausea, flushing, and cramping during faster or comfort-titrated 500 mg NAD+ IV, with symptoms easing when the rate slowed. Slow infusion is a clinic description, not advice.
Is a research-vendor NAD+ vial the same as the Grant 2019 infusion?
No. The study product was a defined compounded IV solution. Catalog listings are a different market. Check lot paperwork. Do not treat a vial as a trial product.
Is this an NMN, NR, or GLP-1 story?
No. NMN and NR are oral precursors with their own trials. NAD+ IV is the molecule itself in a vein. This is not an incretin or pemvidutide article.
This article is for general informational purposes only and is not medical advice. Talk to a licensed clinician about personal medical decisions. NAD+ is an endogenous coenzyme. Injectable NAD+ is not FDA-approved for anti-aging or longevity. Nothing here is a dosing protocol, an availability claim, or a recommendation to obtain an unapproved product.
Continue your research
- NAD+ price and vendor comparison
- NAD+ research profile
- What is NAD+? Beginner guide
- SS-31 (elamipretide) mitochondrial peptide
- Centenarian immune system and where longevity compounds fit
- COA Authenticity Checker
- How to verify a peptide COA
Sources
- Grant R, Berg J, Mestayer R, Braidy N, Bennett J, Broom S, Watson J. A pilot study investigating changes in the human plasma and urine NAD+ metabolome during a 6 hour intravenous infusion of NAD+. Front Aging Neurosci. 2019;11:257. PMID 31572171
- Massudi H, Grant R, Braidy N, Guest J, Farnsworth B, Guillemin GJ. Age-associated changes in oxidative stress and NAD+ metabolism in human tissue. PLoS One. 2012;7(7):e42357. PMID 22848760
- Yang F, Deng X, Yu Y, et al. Association of human whole blood NAD+ contents with aging. Front Endocrinol. 2022;13:829658. PMID 35388296
- Hawkins J, Idoine R, Kwon J, et al. Randomized, placebo-controlled, pilot clinical study evaluating acute Niagen+ IV and NAD+ IV in healthy adults. medRxiv. Posted 10 June 2024. DOI 10.1101/2024.06.06.24308565
- PubChem CID 5892. Nadide / nicotinamide adenine dinucleotide. CAS 53-84-9