RESEARCH DIGEST / DOSE CONTEXT
NAD+ dosage: the doses used in published research.
What was administered, to whom, by which route, for how long — the precursor dose-response as a stack of measured steps. Research context only; no dosing instructions.
The short version
This page reports the doses that appear in published NAD+ studies — nothing more. It does not tell you what to take. Because oral NAD+ (the fuel-handling helper molecule every cell uses) is poorly absorbed, the dose figures here are mostly for its precursors (building blocks the body converts into NAD+ — NMN and NR). In human trials, oral NMN was studied at roughly 250-900 mg/day and oral NR at roughly 250-1000 mg/day. These are research doses in research populations, described so you can read the studies — not a recommendation, and not a protocol for any person.
Doses used in published research
We give no human dosing instructions; the following are the doses studies actually administered, as context for reading them.
Oral NMN (precursor): 250-900 mg/day in human RCTs, with 250 mg/day the most-replicated dose and up to 1200 mg/day studied [1][3][8]. The 60-day multicenter trial spanned 300/600/900 mg/day and named 600 mg/day optimal [3].
Oral nicotinamide riboside (NR, precursor): commonly 250-1000 mg/day, with the dose-response defined at 100/300/1000 mg/day [4] and up to 3000 mg/day tested for safety in the NR-SAFE context. Nicotinamide (NAM) has been studied at 500 mg twice daily for skin-cancer chemoprevention.
IV NAD+ (wellness/clinical): reported infusion protocols of roughly 250-1000 mg per session over several hours; one pharmacokinetic study used a continuous infusion of 3 µmol/min over 6 hours [9].
How much NAD should I take?
We do not give dosing instructions. For context only, human trials studied oral NMN at 250-900 mg/day and oral NR at 250-1000 mg/day, with up to 3000 mg/day NR tested for safety [3][4]. The 60-day NMN trial identified 600 mg/day as its optimal dose [3]. These are research doses administered in study populations, not recommendations for any individual — what you should do is a question for a qualified clinician, not a literature digest.
Routes studied
Oral dosing of NMN, NR and nicotinamide carries the bulk of the controlled human evidence [4][3]. Intravenous NAD+ infusion is used in wellness clinics with limited, mostly pilot or retrospective controlled data [9]. Subcutaneous and intramuscular NAD+ injection are compounded with minimal peer-reviewed pharmacokinetic data, and sublingual, intranasal, topical and transdermal-patch forms are marketed with little controlled evidence. The route with real randomized data is oral precursor dosing; everything else is thinner.
Clearance and half-life in the research
NAD+ itself is not freely taken up intact by most cells, and its behavior differs sharply by route. Infused intravenous NAD+ is rapidly cleared from plasma — a pharmacokinetic pilot found near-complete plasma removal within roughly the first two hours of infusion, with extensive extracellular metabolism [9]. Oral precursors behave on a different timescale: absorbed and converted, they raise whole-blood NAD+ over days to weeks, with the elevation sustained through chronic dosing in 6-12 week trials [4][7]. So there is no single "NAD+ half-life": infused NAD+ clears in hours, while precursor-driven blood NAD+ is a days-to-weeks pharmacodynamic effect.
Adverse events and tolerability reported in trials
In controlled oral precursor trials, tolerability was good. NR up to 1000 mg/day for 8 weeks showed no significant adverse-event difference from placebo and no flushing [4]; NR at 1000 mg/day for 6 weeks caused no serious adverse events [7]. NMN across 60-day and 12-week trials at 250-900 mg/day reported no safety issues and no clinically significant changes in vital signs or labs [3][9].
The NAD+ side effects that do appear cluster on the injectable route: IV NAD+ infusions can cause chest tightness, abdominal discomfort, flushing and nausea if run too fast, generally resolving on completion. Separately, a compounded injectable NAD+ has been subject to an FDA Class I endotoxin recall — a product-quality risk distinct from the drug's pharmacology. A theoretical oncology concern also exists: because NAD+ supports proliferating cells, its role in cancer is context-dependent, and caution is advised in cancer populations. Full adverse events and tolerability detail sits on the FAQ.
Stability and product-quality notes
NAD+ and NMN are hygroscopic and degrade with heat and moisture; reconstituted injectable NAD+ is kept cold and protected from light. Compounded injectables carry contamination and endotoxin risk, the basis of the FDA Class I recall noted above. Supplement-grade products also vary widely in purity and actual content, and third-party testing is not guaranteed — a quality caveat that applies across the precursor market and is independent of the trial data.