NAD+: uses, evidence and status | Inside Your Peptides

compound file

The answer, first. A coenzyme every cell uses to carry electrons through energy metabolism, described in 1906. Sold since the 2010s as an injectable and as oral precursors. The strongest evidence is for raising blood NAD+ with oral precursors, graded B — one well-powered human trial.

Oral nicotinamide riboside raises NAD+ reliably. Whole blood NAD+ rose about 60% against placebo over 6 weeks at 1 g daily in 30 adults ³.

Single doses raise it dose-dependently ². Oral precursor, not the injectable. The rest of what it is sold for — energy, fatigue and anti-aging by injection, muscle mitochondrial function — grade D or E: animal or mechanism data only, or a claim the human trials have already tested and not supported.

What it is used for

Every use graded on its own evidence, not the compound as a whole. 6 outcomes, ranked by what the human record supports.

#outcome · human · animal · gradewhat the best evidence actually shows

01Raising blood NAD+ with oral precursorsmultiple randomized trials agreeing · extensivegrade BOral nicotinamide riboside raises NAD+ reliably. Whole blood NAD+ rose about 60% against placebo over 6 weeks at 1 g daily in 30 adults ³. Single doses raise it dose-dependently ². Oral precursor, not the injectable.

02Raising blood NAD+ by injectionone uncontrolled infusion pilot · none by this routegrade CA 6-hour intravenous infusion at 3 micromoles per minute produced no rise in plasma NAD+ or its metabolites before hour 2 ¹. NAD+ was excreted in urine by hour 6. One uncontrolled pilot, no control arm.

03Insulin sensitivity with oral precursorsone small positive, one larger null · positive in rodentsgrade COne 10-week randomized trial of oral NMN in postmenopausal women with prediabetes raised clamp-measured glucose disposal ⁴. It drew published criticism, and a 12-week trial of 2 g nicotinamide riboside daily in 40 obese men found no change ⁵⁹.

04Parkinson's diseasephase 1, 30 participants · supportivegrade CIn a double-blinded phase 1, 30 newly diagnosed treatment-naive patients took 1,000 mg oral nicotinamide riboside for 30 days. Cerebral NAD+ rose variably, and mild clinical improvement tracked those who responded ⁸. Phase 1, not an efficacy result.

05Energy, fatigue and anti-aging by injectionno controlled trial by this route · precursor work onlygrade DNo randomized trial has given injected NAD+ for any symptom or outcome, in any population ¹. The entire clinical NAD+ literature is oral precursors, which is a different molecule taking a different path.

06Muscle mitochondrial functiontwo randomized trials · positive in rodentsgrade EOral trials closed this one. In 12 aged men, 1 g nicotinamide riboside daily for 21 days raised the muscle NAD+ metabolome without changing mitochondrial bioenergetics ⁶. A 12-week trial found no change in muscle respiration ⁷.

gradewhat it means

ARegulatory approval, or multiple adequately-powered trials agreeing with each other

BAt least one well-powered human randomised trial, with the direction replicated

CSmall or open-label human trials only

DAnimal or mechanism data only, with no controlled human outcome

EA claim the human trials have already killed

How it works

The proposed mechanism, in three steps. A mechanism is a reason to run a trial, never a substitute for one.

1targetNAD+ carries hydride between hundreds of dehydrogenases and is consumed as a co-substrate by sirtuins and related enzymes ³.

2signalNAD+ is modulated by metabolic stress and reported to decline with aging in preclinical models, with sparse human data ⁶.

3effectRaising the pool with an oral precursor shifts the muscle NAD+ metabolome and lowers circulating inflammatory cytokines, without changing bioenergetics ⁶.

What it does not do

Claims the current record does not support. Worth knowing before you set expectations.

not supported by the evidence

IV NAD+ raises cellular NAD+. The one published human infusion study found no plasma rise for 2 hours and NAD+ leaving in urine ¹. Tissue uptake was never measured.
NAD+ drips reverse aging or treat addiction. No randomized trial of injected NAD+ exists for any indication. The clinic claims rest on oral precursor data and on uncontrolled reports.
Oral precursors improve mitochondrial function. Two randomized trials raised the muscle NAD+ metabolome and found mitochondrial bioenergetics, respiration and content unchanged ⁶⁷.
NAD+ is a peptide. It is a dinucleotide coenzyme. It appears on peptide sites because it is sold beside them, not because it belongs to the class.

How it is used

What published protocols administered, and what the community reports doing. Descriptive on both counts, and never a recommendation.

routeIntravenous infusion over hours in clinics, or subcutaneous injection. The precursors are oral capsules, which is a different route entirely.

formatVials of solution or lyophilised powder for injection. Capsules for the oral precursors.

published dosesThe only published human injection protocol is a 6-hour intravenous infusion at 3 micromoles per minute ¹. Oral precursor trials dosed 1 g nicotinamide riboside daily for 21 days ⁶. Others used 500 mg twice daily for 6 weeks ³, and 2 g daily for 12 weeks ⁵. No injectable dose has been trialled against an outcome.

human pharmacokineticsA 6-hour infusion produced no plasma NAD+ rise before hour 2, then urinary excretion of NAD+ and methylnicotinamide ¹.

reported conventionsAs reported on longevity forums and clinic pages, 2018-2026: intravenous drips of several hundred milligrams over one to four hours. Drips are repeated across a course of days. Or smaller subcutaneous amounts daily. Infusion speed is what people describe most. Convention, not guidance.

commonly paired withGlutathione SS-31

This site does not publish protocols to follow. The doses above are what studies administered or what users report, stated as facts about the literature and the market. How protocols are structured, mixing and storage and the reconstitution calculator cover the arithmetic.

What to expect

Where a trial measured it, the trial. Where only the community reports it, that is said out loud.

onsetNo trial measured symptom onset for injected NAD+. As reported: an effect during the drip itself rather than after it, which describes the infusion rather than NAD+ status. The oral precursor trials measured blood NAD+ rather than feelings, and it rises within hours of a single dose ².

most common reportAs reported: chest pressure, flushing and nausea during a fast drip, easing when the rate is slowed. That is a rate effect.

adverse effectsNo trial has published adverse event rates for injected NAD+. As reported: infusion-rate reactions, chest tightness, nausea and headache. Oral precursor trials found no serious adverse events attributable to the supplement across 12 weeks at 2 g daily ⁵.

the stop signalAs reported: clinics slow or stop the drip when infusion symptoms appear, which is a tolerability signal and not an efficacy one. No published stopping rule exists.

Approval and status

What regulators and sport bodies have actually said, separately from what the evidence shows.

approvalNo approved injectable NAD+ product. Precursors are sold as dietary supplements.

FDANo approved product by any route. The dietary supplement status of the oral precursors has been contested.

sport [WADA]Not listed. Infusions over 100 mL per 12 hours are prohibited under M2.

sold asresearch chemical

Check the vial

The grade above describes a molecule studied under controlled conditions. It says nothing about the powder in a particular vial.

That gap is the one part of this market a reader can actually close. How to read a certificate of analysis covers the five measures in five minutes, and the 2026 audit grades vendors on the documents they publish against a rubric printed in full.

Questions we get

What is NAD+ used for?

Injected, nothing with trial support. It is sold for energy, aging, brain fog and addiction recovery. The published human record belongs almost entirely to the oral precursors. They reliably raise blood NAD+ ²³ and then largely fail to move mitochondrial function ⁶⁷.

Injected NAD+ has one pharmacokinetic pilot and no controlled outcome trial for any indication ¹.

How is NAD+ used?

Descriptively, and not as guidance: intravenous drips of several hundred milligrams over one to four hours in clinics, or smaller subcutaneous amounts. The one published human infusion protocol ran 6 hours at 3 micromoles per minute ¹.

The oral precursor trials used 500 mg twice daily ³, 1 g daily ⁶⁸, or 2 g daily ⁵, by capsule.

How long does NAD+ take to work?

For blood levels, hours: a single oral precursor dose raises the blood NAD+ metabolome the same day ². For anything a person would notice, unknown, because no controlled trial of injected NAD+ has measured a symptom.

The infusion pilot found NAD+ did not even appear in plasma for the first 2 hours ¹.

Is injectable NAD+ the same as oral NR or NMN?

No, and almost all the human evidence belongs to the oral ones. Nicotinamide riboside and nicotinamide mononucleotide are precursors that the body converts. Injected NAD+ is the finished coenzyme. The single published human infusion study found no plasma rise for the first 2 hours, and NAD+ turned up in the urine ¹.

Do NAD+ drips do anything?

No randomized trial has tested one, for any indication. What exists is a pharmacokinetic pilot ¹ and uncontrolled clinic reports. The oral precursor trials that do exist raise blood NAD+ reliably ²³.

They have repeatedly failed to move muscle mitochondrial function ⁶⁷ or insulin sensitivity in men ⁵. Raising a molecule is not the same as producing a benefit.

References

Grant R, Berg J, Mestayer R, et al. 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
Trammell SA, Schmidt MS, Weidemann BJ, et al. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans. Nat Commun. 2016;7:12948. PMID 27721479
Martens CR, Denman BA, Mazzo MR, et al. Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. Nat Commun. 2018;9:1286. PMID 29599478
Yoshino M, Yoshino J, Kayser BD, et al. Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science. 2021;372:1224-1229. PMID 33888596
Dollerup OL, Christensen B, Svart M, et al. A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects. Am J Clin Nutr. 2018;108:343-353. PMID 29992272
Elhassan YS, Kluckova K, Fletcher RS, et al. Nicotinamide riboside augments the aged human skeletal muscle NAD+ metabolome and induces transcriptomic and anti-inflammatory signatures. Cell Rep. 2019;28:1717-1728. PMID 31412242
Dollerup OL, Chubanava S, Agerholm M, et al. Nicotinamide riboside does not alter mitochondrial respiration, content or morphology in skeletal muscle from obese and insulin-resistant men. J Physiol. 2020;598:731-754. PMID 31710095
Brakedal B, Dolle C, Riemer F, et al. The NADPARK study: a randomized phase I trial of nicotinamide riboside supplementation in Parkinson's disease. Cell Metab. 2022;34:396-407. PMID 35235774
Brenner C. Comment on nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science. 2021;373:eabj1696. PMID 34326206

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