# NAD+ Doses Used in the Research (No Human Dosing Guidance)

> NAD+ research doses: NMN 250-900 mg/day and NR 250-3000 mg/day were studied orally; IV NAD+ infused over hours. A research-framed reading - not dosing advice - with tolerability and side effects from the trials.

What researchers administered, to whom, by which route, and how it was tolerated. This is a reading of the literature, with no human dosing instructions.

## Read this first

This page reports the doses used in NAD+ studies so the numbers can be checked against their sources. It is not dosing guidance and gives no instruction to take any amount. Almost every controlled human number here is for a precursor (NMN or NR), not for intact NAD+ - the precursor is what the trials gave by mouth, because NAD+ itself is poorly absorbed. Doses are written the way the studies wrote them (milligrams per day, for a stated number of weeks, in a stated population). Where a result has a tier, this page marks it: established human findings, preliminary signals, and buyer-beware cautions are kept apart.

## Doses used in the research

In randomized human trials, oral NMN was studied at 250-900 mg/day; 250 mg/day is the most-replicated dose, and doses up to about 1200 mg/day have been studied [1][3]. The 250 mg/day NMN regimen for 10 weeks is the one that improved muscle insulin sensitivity in prediabetic postmenopausal women [1]; the 300/600/900 mg/day NMN regimen for 60 days raised blood NAD+ at every dose, with 600 mg/day flagged as optimal [3]. Oral [nicotinamide riboside (NR)](/nmn-vs-nr) was commonly studied at 250-1000 mg/day, with 3000 mg/day tested for safety (the NR-SAFE trial in Parkinson's disease) [4]. At 100/300/1000 mg/day for eight weeks, NR raised whole-blood NAD+ by 22%/51%/142% in a dose-dependent fashion [4]. Plain nicotinamide has been studied at 500 mg twice daily for skin-cancer chemoprevention [16]. For IV NAD+, reported wellness protocols run roughly 250-1000 mg per session over several hours, and one pharmacokinetic study used a 3 micromol/min continuous infusion over six hours [16].

## Routes studied and how NAD+ persists

Oral capsules and powders of NMN, NR and nicotinamide carry the bulk of the controlled human evidence [3][4]. Intravenous NAD+ infusion is used in wellness clinics but rests on limited, mostly pilot or retrospective data; subcutaneous and intramuscular NAD+ injection are compounded with minimal peer-reviewed pharmacokinetics; and sublingual, intranasal, topical and transdermal-patch forms are marketed with little controlled evidence [16]. Persistence differs sharply by route. Intact NAD+ is not freely taken up by most cells, and infused IV NAD+ is rapidly cleared from plasma - a pilot study found near-complete plasma removal within the first roughly two hours of infusion [16]. Oral precursors behave differently: they are absorbed and raise whole-blood NAD+ over days to weeks, with the elevation sustained through chronic dosing across 8-12-week trials [4]. NAD+ and NMN are also hygroscopic and degrade with heat and moisture, and reconstituted injectable NAD+ should be kept cold and protected from light [16].

## Tolerability and adverse events reported in trials

Oral precursors were well tolerated across the controlled trials. In the eight-week NR study at up to 1000 mg/day, there were no significant adverse-event differences from placebo, no flushing, and no rise in LDL cholesterol [4]; NR at 3000 mg/day for 30 days in the NR-SAFE design was tolerated [4]. The multicenter NMN trial reported no safety issues at any dose up to 900 mg/day [3]. The cautions sit on the injectable side. IV NAD+ infusions can cause chest or abdominal discomfort, flushing and nausea if run too fast, and the symptoms reported in tolerability accounts resolved on completion of the infusion [16]. The hard caution is contamination: a compounded injectable NAD+ product was subject to an FDA Class I recall for elevated bacterial endotoxin [16]. NAD+, NMN, NR and nicotinamide are not prohibited by the World Anti-Doping Agency [16].

## Why these are study doses, not a protocol

Every figure on this page describes what was administered in a study, in a defined population, for a defined duration - it is not a personal dose and not a schedule to follow. Functional results are dose- and population-specific (the insulin-sensitivity result was at 250 mg/day NMN in prediabetic postmenopausal women [1]; the blood-NAD+ dose-response was NR in healthy overweight adults [4]), so a number lifted out of its study does not carry its meaning with it. The literature also does not establish an optimal time of day or an injection schedule. This site reports the research and points to the [study references](/references); it does not tell anyone what to take.

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A due-diligence console for the NAD+ literature - oral-precursor trials graded established, poorly-absorbed oral NAD+ and rapidly-cleared IV infusions held apart, and the contested NMN supplement status read as filed; no clinic behind the readout and nothing here dosed, prescribed, or sold.