NAD+

NAD+ is short for nicotinamide adenine dinucleotide. It is not a peptide. The published description is a redox cofactor, meaning a helper molecule the body's chemistry uses in reactions that pass electrons back and forth. On a certificate it carries the public database identifier PubChem CID 5892, the formula C21H27N7O14P2 and a weight of 663.4 grams per mole. Two other substances are sold to raise it and are spoken about constantly as though they were the same thing: nicotinamide riboside and nicotinamide mononucleotide, which the published literature calls precursors, that is starting materials the body builds NAD+ out of, rather than NAD+ itself. Those two are the things most people have actually taken, and they are swallowed. NAD+ itself is sold as a bag dripped into a vein in a clinic and as an injection under the skin at home. Hold the three apart, because every argument for the drip depends on letting them run together.

The defining fact about this compound is that intact NAD+ does not enter cells. Enzymes sitting on the outside of the cell, CD38 and CD73 among them, take it to pieces before anything crosses, breaking it into nicotinamide mononucleotide, nicotinamide riboside and nicotinamide. Of those, the nucleotides do not cross the membrane around the cell at all. NAD+ does not cross. Nicotinamide mononucleotide does not cross. What crosses is the nucleoside, nicotinamide riboside, and the base, nicotinamide, with nicotinamide mononucleotide getting in only once CD73 has stripped its phosphate off and turned it into nicotinamide riboside, and those fragments rebuild the supply inside. It is the wardrobe that will not go up the stairs: the delivery men take it apart on the pavement, carry the panels up one at a time, and what arrives in the bedroom is panels, whatever the invoice said. The number that would settle whether a bag beats a capsule is the share of a dose that arrives inside a cell as NAD+ rather than as a fragment, and I found no study in an infused human measuring it.

This entry does not survey what buyers say they are after, so what follows is where the practice came from and what hospitals have registered it for. The drip is sold in wellness clinics, several hundred milligrams over a few hours in a chair. The amounts trace to one specific place, the Springfield Wellness Center BR+NAD addiction protocol, whose supporting 60 patient study gave NAD+ into a vein at 500 to 1500 mg daily for about ten consecutive days, five to ten hours daily, alongside vitamins, amino acids taken by mouth, a substance named only by the initials NAC, and other medicines as needed. NAD+ was one of several things going in, and the work was presented as a Society for Neuroscience poster in 2014 with no peer-reviewed publication I could find. What hospitals have registered is different and far smaller. China approved an injectable form as Coenzyme I for Injection, regulator registration H41024721, for disease of the arteries that feed the heart, for a low white blood cell count, and for inflammation of the heart muscle, in a 5 mg vial. A registered trial, NCT06776510, gives 100 mg into a vein daily for a week for a condition in which the immune system destroys the blood cells that help the blood to clot, and that is the highest registered human dose into a vein these searches found.

Two mistakes, and the dangerous one is about speed rather than amount. What people compare is milligrams, when the figure that separates the two published infusions is milligrams per minute. Grant put 750 mg into eight men at about 2 mg per minute and recorded nothing at all. The clinic in Reyna 2026 put 500 mg into six clients at roughly 5 mg per minute and every one of them was ill. Bigger dose, slower, no symptoms. Smaller dose, faster, moderate to severe symptoms in everybody. That contrast is the entry writer's own arithmetic on their published figures and it is a hypothesis rather than a finding, and I found no study that has tested infusion rate as a variable for NAD+ given into a vein, so a shorter appointment is a variable nobody has measured. The second mistake is what the persuading evidence is actually about. A 2026 Nature Metabolism trial ran the three oral options against each other in 65 healthy participants over 14 days, at 0.5 g nicotinamide, 1 g nicotinamide riboside and 1 g nicotinamide mononucleotide once daily, and found nicotinamide riboside and nicotinamide mononucleotide comparably raise circulating NAD+ while nicotinamide does not. All oral, all precursors, none of it evidence about injected NAD+. Nor is it flattering on its own terms, since a 2023 Science Advances review of the entire human record for nicotinamide riboside taken by mouth concluded that supplementation has displayed few clinically relevant effects. The drip is sold on evidence generated by swallowing something else.

What happened at the commercial clinic is the clearest signal in the record. All six clients who received NAD+ reported moderate to severe symptoms during the infusion: abdominal cramping, diarrhoea, nausea, vomiting, a raised heart rate, throat pain, congestion and chest pressure. The eight on nicotinamide riboside had minor tingling and cramping, and symptoms stopped when the infusion stopped. On tolerability grounds the NAD+ bags had to be run far more slowly, 97 minutes on average against 37 minutes for nicotinamide riboside. Against that, Grant 2019 observed no adverse events in either the NAD+ group or the salt water group at 750 mg over six hours. Separately, the Food and Drug Administration says it has received adverse event reports of severe chills, shaking, vomiting and fatigue after NAD+ injectable drugs, some requiring medical treatment, which it describes as consistent with excessive endotoxin, a contaminant left behind by bacteria. It classified a recall by GenoGenix LLC of NAD+ for Injection, at 100 mg per millilitre and 200 mg per millilitre, as Class I for elevated endotoxin, recall number D-0094-2026. Sterility was not in question at the clinic Reyna studied, so contamination and the infusion itself are two separate problems rather than one. NAD+ is not a Food and Drug Administration approved drug for any indication in the United States, and in a proposed rule published 5 September 2019 under docket FDA-2018-N-4845 the agency proposed leaving it off the list of bulk substances that pharmacies may compound from, one of 26 substances proposed for exclusion, because it degrades on exposure to light, moisture, alkaline pH or room temperature, because the non-clinical and clinical data were inadequate, and because no published studies supported the nominated use. Whether that proposal was finalised the entry writer could not confirm, because every page tried on the agency's website returned an error.