Community Consensus
Community Consensus
Reader sentiment on the compounds this article compares. Votes count toward each compound's own tally.
Reader sentiment only. Not medical advice, not a recommendation, and not a measure of evidence quality.
Quick answer
NAD+ nasal sprays, transdermal patches and liposomal NAD+ all exist because NAD+ taken by mouth is not effectively absorbed, and the routes that work for the molecule itself, IV infusion and subcutaneous injection, need a needle and usually a clinic. Each alternative has a plausible mechanism and none has a published human trial showing it raises NAD+ in blood or tissue. Nasal NAD+ rests on rat stroke studies with no human pharmacokinetics. Patches rest on transdermal chemistry that argues against them, since NAD+ is large, charged and water-soluble, the three properties that most reliably block skin absorption. Liposomal NAD+ is the most credible and most actively researched of the three, and its absorption in humans remains unclear rather than disproven. If you want an oral route with human evidence, the precursors NMN and NR have it. If you want NAD+ itself, injection is the route with the research.
Key takeaways
- Plain oral NAD+ is largely broken down in the gut, which is the whole reason precursors and alternative routes exist.
- IV and subcutaneous NAD+ are the established routes for delivering the molecule itself; the alternatives are attempts to sell that without the needle.
- No published human trial shows that a nasal spray, a patch, or a liposomal formula raises NAD+ in blood or tissue.
- Liposomal NAD+ is the most credible of the three, is under active research, and its absorption in humans is unclear rather than negative.
- Even a liposome that survives digestion has to deliver NAD+ to cells that mostly cannot import it directly, which may make it an expensive precursor.
- Intranasal NAD+ reduced brain injury in rat stroke models. That is the entire evidence base for nasal sprays and it has not been extended to humans.
- Nasal delivery is dose-limited by a small surface and fast clearance, so a few sprays deliver a fraction of what an infusion does.
- NAD+ is around 663 daltons, water-soluble and negatively charged, which makes passive skin penetration unlikely. No study shows patches deliver it.
- Patches that add caffeine, B vitamins or menthol produce a sensation that has nothing to do with NAD+.
- A burst of alertness within minutes of a nasal spray argues against NAD+ being responsible, since even IV NAD+ takes hours to change plasma levels.
- NAD+ is unstable in solution, so sprays and liposomal liquids are more likely than capsules to contain less than the label says. Ask for a certificate of analysis.
- For an oral route with human evidence, NMN and NR have the trials; for NAD+ itself, injection is a clinical decision.
The short answer
NAD+ nasal sprays, transdermal patches and liposomal NAD+ all exist to solve the same problem: NAD+ taken by mouth is not effectively absorbed, and the routes that do work, intravenous infusion and subcutaneous injection, involve a needle and usually a clinic. Each alternative route has a plausible story and none has a published human trial showing it raises NAD+ in blood or tissue. Nasal NAD+ rests on rat studies. Patches rest on the general chemistry of skin, which is unfavorable for a large, charged molecule like NAD+. Liposomal NAD+ is the most actively researched of the three and its absorption in humans is still unclear. If you want an oral route with human evidence behind it, the precursors NMN and NR have it. If you want NAD+ itself, injection is the route with the research.
Why these products exist
NAD+ is a large, water-soluble, negatively charged molecule, around 663 daltons, and cells do not take it up readily from outside. Swallowed, it meets an intestinal lining and a liver that between them dismantle it into nicotinamide and other fragments before it reaches the bloodstream intact. That is not a controversial finding; it is why the entire NAD+ precursor industry exists. NMN and nicotinamide riboside are smaller, pass through the gut differently, and reliably raise blood NAD+ in human trials, which is covered in the NAD+ pillar.
Injected NAD+ solves the problem by skipping the gut entirely. IV and subcutaneous NAD+ are the established routes for delivering the molecule itself, and they have the clinical use and the pharmacokinetic study behind them. What they do not have is convenience, and the three products in this article are attempts to sell the injected molecule without the needle.
The three routes, compared
| Route | The delivery argument | Human evidence it raises NAD+ | What the evidence actually is |
|---|---|---|---|
| Oral NAD+ (plain) | None; sold on the name | No | Largely broken down in the gut; not an effective route |
| Liposomal oral NAD+ | Lipid shell shields the molecule through digestion | No published trial | Under research; absorption unclear; some unpublished manufacturer data |
| Nasal spray | Nasal mucosa absorbs directly, possibly to the brain via olfactory nerves | No | Rat stroke studies with intranasal NAD+; no human pharmacokinetics |
| Transdermal patch | Slow release through skin, sometimes with an electrical current (iontophoresis) | No | No published data for NAD+; the molecule’s size and charge make passive skin penetration unlikely |
| IV infusion / subcutaneous injection | Direct to blood or tissue | Yes (pharmacokinetics) | Established clinical route; decades of use; one published PK study; no outcome RCTs |
| NMN / NR (oral precursors) | Smaller molecules; cells rebuild NAD+ from them | Yes (multiple RCTs) | Reliably raise blood NAD+; clinical benefits mixed |
⚠ CLAIM (wellness): No published human trial demonstrates that NAD+ nasal spray, transdermal NAD+ patches, or liposomal oral NAD+ raise NAD+ levels in blood or tissue. Oral precursors (NMN, NR) and injected NAD+ are the routes with human pharmacokinetic evidence. Basis: absence of published human data for the three alternative routes; Martens 2018; Yi 2023; Grant 2019. Lane: educational.
Liposomal NAD+
This is the most credible of the three, and the one with real research activity behind it. Liposomes are microscopic fat bubbles that can carry a water-soluble payload through the stomach and intestine and deliver it to the intestinal lining relatively intact. The technology works for some molecules, including glutathione, where the human evidence is discussed in best glutathione supplement. Whether it works for NAD+ is the open question, and the answer is genuinely unclear rather than negative.
The obstacles are specific. Even a liposome that survives digestion has to release NAD+ at a cell that can use it, and cells generally cannot import NAD+ directly; they import precursors and rebuild it. So a liposome that delivers intact NAD+ to the gut wall may simply be delivering it to the same enzymes that would have broken it down anyway, one step later. Some animal work suggests oral NAD+ can raise tissue NAD+ through its breakdown products, which would make liposomal NAD+ an expensive precursor rather than a way to deliver the molecule itself. Manufacturer-sponsored studies claiming absorption exist, but none we could find has been published in a peer-reviewed journal with the plasma NAD+ time course a claim like that needs.
The fair summary: liposomal NAD+ is being researched, its absorption is unclear, and buying it today means paying an injection-route price for a product with less human evidence than a bottle of NMN.
NAD+ nasal spray
The nasal route has a real scientific basis, just not in humans. Intranasal delivery can move some molecules across the nasal lining and, for a subset, along the olfactory and trigeminal nerves toward the brain, bypassing the blood-brain barrier. Intranasal NAD+ was given to rats in stroke models and reduced the size of the brain injury, which is where the idea came from. That is interesting neuroscience and it has not been followed by a human pharmacokinetic study, let alone an outcome trial.
Two practical issues. The nasal lining is a small surface with a fast clearance rate, so the dose that can be delivered is limited to what a few sprays hold, typically a fraction of what an infusion delivers. And the marketing claim of “direct to brain” is doing a lot of work: even in the animal studies, the amount reaching the brain was modest, and the rat nasal cavity is proportionally far larger relative to brain size than a human’s. A nasal spray is convenient, and convenience is what it is selling. Users report a stinging or burning sensation with some products, and some describe short-lived alertness that has not been distinguished from the effect of spraying anything cold up your nose.
NAD+ patches
Transdermal delivery works for small, moderately fat-soluble, uncharged molecules: nicotine, estradiol, fentanyl, scopolamine. NAD+ is none of those things. It is large, water-soluble and carries a negative charge, which are the three properties that most reliably stop a molecule from crossing the outer layer of skin. Some patches add a small electrical current (iontophoresis) to push charged molecules through, and that technology does move some drugs, but there is no published study, in animals or humans, showing it delivers a meaningful amount of NAD+.
The patches also tend to carry small stated doses, and some add caffeine, B vitamins or menthol, which produce a noticeable sensation that has nothing to do with NAD+. Of the three routes here, the patch is the one with the least going for it: no human data, no animal data, and chemistry that argues against it.
⚠ CLAIM (wellness): NAD+ is a large, charged, water-soluble molecule with properties that make passive transdermal absorption unlikely, and no published study demonstrates that NAD+ patches deliver the molecule through skin. Basis: general principles of transdermal drug delivery; absence of published NAD+ transdermal data. Lane: educational.
What people report
Anecdotal experience, separated from the evidence above. None of it shows these products raise NAD+.
- Nasal sprays: a short burst of alertness or clarity within minutes is the common report, along with stinging. The speed of onset is actually a mark against NAD+ being responsible, since even IV NAD+ takes hours to change plasma levels.
- Patches: most reports describe no effect. Where people do report energy, the patch usually also contains caffeine or B vitamins.
- Liposomal NAD+: reports are mixed and look like the NMN reports, mostly nothing noticeable, occasionally better energy after weeks. Digestive upset is reported with some products, which is common to liposomal formulations generally.
How to think about this
If the goal is raising NAD+ by mouth, the precursors have the trials and these products do not. Choosing a supplement in that category is covered in best NMN supplement. If the goal is NAD+ itself, injection and infusion are the established routes and they are a clinical decision, with their own side effect profile described in NAD+ supplement side effects. The alternative routes are a bet that a molecule which does not cross the gut will cross the nose or the skin instead, and nobody has yet published the study that would settle the bet.
If you do try one, treat it as an experiment with a cost and no expected result, and apply the same standard as for any NAD+ product: a certificate of analysis showing the stated NAD+ content, because NAD+ is unstable in solution and a spray or liposomal liquid that has sat on a shelf may contain little of what the label says. Stability is a bigger problem for liquids than for capsules, and the burden of proof is on the product.
Educational information only, not medical advice, and not evaluated by the FDA. None of these products is a treatment for any disease. Injected and infused NAD+ are clinical procedures and are not covered here. Talk to a clinician before using NAD+ products if you have a current or previous cancer diagnosis, take prescription medication, or are pregnant or breastfeeding.
Frequently asked questions
Does NAD+ nasal spray work?
There is no human evidence that it does. The idea comes from rat studies in which intranasal NAD+ reduced brain injury after an induced stroke, which is real neuroscience but has not been followed by a human study measuring whether a spray raises NAD+ in blood or brain. Nasal delivery is also dose-limited, because the nasal lining is a small surface that clears quickly, so a few sprays deliver far less than an infusion. The quick alertness some users describe arrives faster than NAD+ could plausibly act. This is educational information, not medical advice.
Do NAD+ patches work?
Nothing published suggests they do. Transdermal delivery works for small, moderately fat-soluble, uncharged molecules such as nicotine or estradiol. NAD+ is large, water-soluble and negatively charged, which are the three properties most likely to stop a molecule crossing the outer skin. Patches that use a small electrical current can push some charged drugs through, but no study in animals or humans shows this delivers a meaningful amount of NAD+. Many patches also contain caffeine or B vitamins, which explains the sensation people report.
Is liposomal NAD+ absorbed?
Unclear, and this is the one route where unclear is the honest word rather than a polite no. Liposomes can carry water-soluble molecules through digestion, and the approach works for some compounds. For NAD+ the difficulty is that even an intact liposome has to hand its cargo to cells that mostly cannot import NAD+ directly, so it may end up delivering the same breakdown products a plain capsule would, one step later. Manufacturer studies claiming absorption exist, but no peer-reviewed human trial with a plasma NAD+ time course has been published. It is being researched; it is not established.
What is the best way to take NAD+?
It depends what you mean by take. If you want NAD+ itself in your bloodstream, intravenous infusion and subcutaneous injection are the established routes with clinical use and pharmacokinetic data, and they are a decision to make with a prescriber. If you want an oral route with human trial evidence, the precursors NMN and nicotinamide riboside reliably raise blood NAD+. The nasal, patch and liposomal products sit in between, offering convenience with no published human evidence that they deliver.
Why can't you just swallow NAD+?
You can, but it does not survive the trip. NAD+ is dismantled in the intestine and liver into nicotinamide and other fragments before it reaches the bloodstream intact, and cells do not readily import whole NAD+ from outside anyway; they import precursors and rebuild it. Some animal work suggests oral NAD+ can still raise tissue levels through those breakdown products, which would make it an inefficient precursor rather than a way to deliver the molecule itself.
Does NAD+ nasal spray reach the brain?
In rats, some did. Intranasal delivery can move certain molecules along the olfactory and trigeminal nerves and bypass the blood-brain barrier, and this is how intranasal NAD+ reduced stroke damage in rat models. Whether a meaningful amount reaches the human brain is untested, and the rat nasal cavity is proportionally far larger relative to brain size than a human's, so the animal result may not scale. The direct-to-brain claim on product labels is a hypothesis dressed as a feature.
Are NAD+ nasal sprays and patches safe?
Nothing suggests they are dangerous, and nothing has studied them. Nasal sprays commonly cause stinging or burning, and some products contain preservatives that irritate the nasal lining with repeated use. Patches can cause skin irritation at the site, particularly the iontophoretic type. The main cost is financial: these products are priced near the injection route with less evidence than a capsule of NMN. Anyone with a cancer history should ask an oncologist before using any NAD+ product, because the effect of raising NAD+ on existing tumors is an open question.
How do I know if an NAD+ spray or liposomal product contains what it says?
Ask for a certificate of analysis from an independent lab, dated near the batch, showing NAD+ content by chromatography. NAD+ is unstable in water, so a spray or liposomal liquid that has sat on a shelf may contain substantially less than the label states, and a product with no certificate should be treated as untested. This matters more for liquids than for capsules, and more for NAD+ than for most supplements.
References
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- 2.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.
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- 4.Bogan KL, Brenner C. Nicotinic acid, nicotinamide, and nicotinamide riboside: a molecular evaluation of NAD+ precursor vitamins in human nutrition. Annu Rev Nutr. 2008;28:115-130.
- 5.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.
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- 12.National Institutes of Health, Office of Dietary Supplements. Dietary Supplements: What You Need to Know.