STAGE 05 / DOSE CONTEXT
NAD+ Dosage and Routes as Studied in the Research
What the trials administered — oral precursor ranges, the compounded injectable route, and how the body handles each — reported as research context, never as instructions.
The short version
This page reports NAD+ dosage the way the studies report it — which doses were given, to whom, by which route — and nothing more. It is not a how-to. Most controlled evidence is oral, using precursors (the building blocks the body turns into NAD+): NMN around 250-900 mg/day and NR around 250-1000 mg/day in trials. Injectable and IV NAD+ are a different, unapproved story: compounded, lightly studied, and carrying real quality risks. Where you see a number here, it points to a cited study of a defined population. This digest gives no personal dosing advice and recommends no product.
Doses studied in the research literature
In controlled human trials, oral NAD+ precursors clustered in well-defined ranges. NMN was studied at 250-900 mg/day: 250 mg/day for 10 weeks improved muscle insulin sensitivity in prediabetic women [1], and 300, 600, and 900 mg/day for 60 days raised blood NAD+ dose-dependently, with 600 mg/day flagged as optimal [3]. Nicotinamide riboside (NR) was studied at 100-1000 mg/day, producing the 22%/51%/142% whole-blood NAD+ dose-response over eight weeks [4], and was tested up to 3000 mg/day for safety in a Parkinson's-disease study. Nicotinamide (NAM) has been studied at 500 mg twice daily for skin-cancer chemoprevention. These are doses studied in the literature in defined trial populations, reported as research context — not a recommendation to take any amount.
Injectable and IV NAD+: an unapproved compounded route
Injectable and IV NAD+ sit entirely outside the controlled-trial base that supports oral precursors. NAD+ delivered by injection or infusion is a compounded preparation — not FDA-approved — used in wellness and some clinical settings, with only pilot and retrospective data behind it. Reported infusion protocols run roughly 250-1000 mg per session over several hours; one pharmacokinetic study used a continuous 3 micromol/min infusion over six hours. The quality risk is documented, not hypothetical: a compounded injectable NAD+ product was subject to an FDA Class I recall — the agency's most serious category — for elevated bacterial endotoxin. NAD+ and NMN are also hygroscopic and degrade with heat and moisture, and reconstituted injectable NAD+ should be kept cold and protected from light. This is presented as an unapproved compounded route with documented quality concerns, never as an approved treatment.
What controlled data exist on IV NAD+ therapy
IV NAD+ therapy has the weakest controlled evidence in the entire field. The defining pharmacokinetic observation: in a pilot infusion study, plasma NAD+ barely rose for roughly the first two hours of infusion, indicating extensive extracellular metabolism and that infused NAD+ is rapidly cleared from plasma. Most published IV work is pilot or retrospective rather than randomized, and infusion-related symptoms (GI discomfort, chest pressure, flushing) are reported when infusions run fast. No validated clinical benefit or dosing-timing protocol has been established for IV NAD+. The literature does not support broad efficacy claims for this route — a point this digest keeps deliberately unambiguous.
Pharmacokinetics: how the body handles NAD+ and its precursors
The pharmacokinetics explain why route matters so much. NAD+ itself is not freely taken up intact by most cells, which is the practical case for using precursors orally [5]. Infused IV NAD+ is rapidly cleared from plasma — near-complete removal within the first ~2 hours of one pilot infusion. Oral precursors behave differently: NMN and NR are absorbed and raise whole-blood NAD+ over days to weeks, with the elevation sustained through chronic dosing across 8-12 week trials [4][3]. NAD+ synthesis also follows a circadian rhythm because NAMPT, the rate-limiting salvage enzyme, is clock-regulated [14] — biologically interesting, but not translated into any validated dosing-time recommendation. Routes studied span oral (the bulk of the evidence), IV infusion, subcutaneous/intramuscular injection (minimal peer-reviewed PK), and marketed sublingual, intranasal, and transdermal-patch formats with little controlled evidence.