Do NAD+ patches, nasal sprays and liposomal capsules work?

No published study has measured NAD+ in anyone's blood after an NAD+ patch or an NAD+ nasal spray, and the only human data on liposomal NAD+ is one 14-person study, paid for by the product's maker and published in a practitioner magazine that is not peer reviewed. None of the three has been tested in people for any effect on health.

The other routes have more data, some of it only a little more. Below we set out, route by route, what has been measured in people and what has only been seen in animals or lab samples, based on searches of PubMed, Europe PMC and ClinicalTrials.gov in September 2026. We sell an injectable NAD+ kit, so we have a stake in the question, and our own route is in the comparison.

Why does the route matter so much for NAD+?

NAD+ weighs 663.4 daltons (PubChem). In 2000, Bos and Meinardi argued that a compound must weigh under 500 daltons to be absorbed through skin, because larger molecules cannot get past its outer layer, and noted that every drug then used in a transdermal delivery system was under that limit (Bos and Meinardi, 2000). It is a rule of thumb, drawn from which molecules were known to get through, and microneedles are designed to get round it by piercing that outer layer (Prausnitz and Langer, 2008).

That 2008 review said conventional patch drugs need to be small, fat-loving and effective at low doses, typically milligrams a day or less, and that water-loving drugs have been hard to deliver through skin. NAD+ sits at the far end of that scale. PubChem gives it a computed XLogP3 of minus 6, a measure of how a molecule divides between oil and water in which a negative number means it prefers water. It also carries electric charge, which a 2026 paper on skin delivery says hinders its passage across biological membranes (Kang et al., 2026).

Even NAD+ that reaches the blood does not stay there as NAD+ for long. In a 2019 study that infused NAD+ into a vein, plasma NAD+ did not change at all for the first two hours, and the authors concluded the infused NAD+ was being removed from plasma rapidly and completely over that period, with breakdown products that pointed to enzymes cleaving it (Grant et al., 2019). Studies also measure different things. Some test plasma, some whole blood, some the NAD+ inside blood cells, and a 2026 trial found a large rise in whole blood with no change in plasma (Kornilov et al., 2026). When a product says it raises NAD+, it is fair to ask where that was measured.

Do NAD+ patches work?

We found no published study that put an NAD+ patch on people and then measured NAD+ in their blood, and no such trial registered on ClinicalTrials.gov.

The nearest evidence comes from the laboratory. In the 2026 study mentioned above, researchers applied an NAD+ solution to pieces of donated human and pig skin. Plain NAD+ stayed mostly in the outermost layer, while the researchers' experimental formulation, built around tiny lipid vesicles, reached deeper (Kang et al., 2026). That was a solution on tissue in a dish, and the authors name human trials as a step still to come.

Do NAD+ nasal sprays work?

There is no published human data for this route either. Intranasal NAD+ has been given to rats, where a 2007 study found it raised NAD+ levels in the brain (Ying et al., 2007), and to mice, in a 2026 study of an induced loss of smell (Yoo et al., 2026). Neither study gave NAD+ to people.

A small US trial that began in 2025 includes an NAD+ nasal spray at 30mg a day, taken alongside prescription drugs and other supplements, so it cannot show what the spray does alone. It had posted no results when we checked (ClinicalTrials.gov, NCT07475546).

Is liposomal NAD+ better absorbed?

A liposome is a microscopic bubble of fat-like molecules with the ingredient carried inside, meant to protect a fragile, water-loving molecule in the gut and help it through fatty membranes. For NAD+ in people, the idea has barely been tested.

The one human study of an oral liposomal NAD+ product that we found enrolled 14 people, who took 1000mg a day of two versions of the product for two weeks each. There was no placebo group and no randomisation. NAD+ measured in finger-prick dried blood spots rose by an average of 64% (Blair et al., 2026). The company that makes the product funded the study, its authors are the company's owner and two of its employees, and it was published in Naturopathic Doctor News and Review, which is not a peer-reviewed journal. We found no study of liposomal NAD+ benefits beyond that blood measurement.

What about swallowing plain NAD+?

The authors of the trial below note that oral NAD+ has historically been estimated to have a bioavailability below 2% (Kornilov et al., 2026). Their trial, published in GeroScience in 2026, is the only randomised, placebo-controlled study of oral NAD+ we found. It randomised 60 healthy adults aged 45 to 75, with 50 in the main analysis, to five days of either a proprietary oral NAD+ powder, taken four times a day, or a placebo. NAD+ in whole blood rose 53% against placebo by day six, plasma NAD+ did not change, and the only adverse event in the NAD+ group was one case of mild nausea. The powder is a physically modified formulation, the company that supplied it funded the trial, and several authors hold shares or options in that company, so the finding is specific to that product.

Precursors are the best-studied oral option by some distance. A 2026 systematic review found 33 human intervention studies and reported that oral NR and NMN consistently raised NAD+-related measures in blood or cells and were generally well tolerated over weeks to months, while their effects on health outcomes were mixed and often null (Gallagher and Emmanuel, 2026). A precursor is a different molecule that cells build NAD+ from, and our guide to NMN vs NAD+ covers what that difference means.

What does the evidence say for NAD+ IV drips?

IV is where NAD+ itself has been measured most directly in people, and the data is still thin. In the 2019 pilot, eight men received 750mg of NAD+ over six hours and three received saline. Plasma NAD+ did not move for two hours, NAD+ and one of its breakdown products appeared in urine by six hours, and no adverse events were seen during the infusion (Grant et al., 2019).

A 2026 review of clinic records reported a rougher experience. All six clients given 500mg NAD+ drips on four consecutive days reported moderate to severe symptoms during the infusion, including abdominal cramping, nausea, vomiting and chest pressure. The symptoms stopped when each infusion ended, and the authors say they are why the NAD+ drips took longer than drips of NR, a precursor, given in the same clinics (Reyna et al., 2026). It was small and retrospective, with no placebo group, and the company that ran the clinics funded it. The 2026 systematic review found no eligible outcome trials of intravenous or intramuscular NAD+ for anti-ageing or wellness (Gallagher and Emmanuel, 2026). If you are weighing a clinic drip against something at home, our page on NAD+ IV drip alternatives in the UK sets out the practical differences.

What about NAD+ injections under the skin?

This is the route our kit uses: a pre-mixed 1000mg NAD+ vial with a reusable metal auto-injector, given as a subcutaneous injection at home. We found no published study that measured NAD+ in people's blood after NAD+ was injected under the skin, and no outcome trials. Our reasoning is on our science page: an injection skips the digestive tract, where much of an oral dose is broken down, and it avoids the skin barrier described above. That is reasoning from how the molecule behaves. Nobody, us included, has yet published the blood measurements that would test it for this route.

Our NAD+ injection kit page lists what is in the box. Speak to a doctor first if you are pregnant, breastfeeding, taking prescribed medication or under medical supervision. The kit is not for under-18s.

The routes side by side

NAD+ patches in the UK: how to read the label

Search for "NAD patches UK" or "liposomal NAD" and you will find plenty of products. Whatever the route, a seller should be able to answer these questions:

• Which molecule is in it? NAD+ itself, or a precursor such as NMN, NR or nicotinamide? A product name that mentions NAD+ does not say which, so read the ingredient list.
• How much is in it, and how much gets in? A patch label gives the amount in the patch. Only a study in people can show how much reaches the blood.
• Where was it measured? A result from skin samples in a lab describes the formulation. A result in human blood is closer to the question you care about, and plasma, whole blood and blood cells can still give different answers.
• If it is liposomal, is there evidence the liposomes are present, such as a particle size measurement, and has that product been tested in people?
• Is each batch tested? A certificate from an independent laboratory for the batch you receive, stating purity and the method used, is a reasonable thing to ask for.

Our guide to choosing an NAD+ supplement in the UK goes further into testing and labels.