Does NAD+ injection actually work? What the evidence says

Medically reviewed by Elena Gizzi | MSN, RN on September 5th, 2026. Published on September 4th, 2026. Updated on September 9th, 2026.

Longevity & Wellness NAD+

NAD+ is the coenzyme your cells use to turn food into energy. Clinics and telehealth companies sell NAD+ injections for energy, focus and healthy aging.

The trials so far: oral NAD+ precursors raise blood NAD+ in randomized studies, a randomized trial of intravenous NAD+ improved heart function in cardiac patients, and a 6-hour intravenous infusion in healthy adults caused no adverse events. No published trial has tested injected NAD+ for energy, focus or aging in healthy adults, so the question is open rather than settled.

The injuries FDA has recorded came from endotoxin-contaminated compounded vials, including a lot that its maker released without any finished-product testing. You cannot remove that risk, but you can ask who made the vial and whether it was tested. Measured connects you with a licensed provider and a state-licensed pharmacy, screens you first, and tells you what NAD+ can and cannot be expected to do.

Key takeaways

NAD+ sits at the center of cellular energy production, and oral precursors (NR, NMN) raise blood NAD+ in randomized trials. Whether raising it changes how you feel is the open question.
A 2026 PRISMA-guided systematic review found no outcome trials of intravenous or intramuscular NAD+ for wellness, and no published trial covers subcutaneous NAD+, the at-home route telehealth companies (including Measured) prescribe. Researchers have not run the test yet.
The trials that exist are reassuring on tolerability: the 2019 intravenous pilot in healthy adults saw no adverse events over a 6-hour 750 mg infusion, and a 2026 randomized trial of intravenous NAD+ in heart-failure patients met its primary endpoint.
The NAD+ injuries FDA has documented involved endotoxin-contaminated compounded products, including a lot released with no finished-product testing by a firm that later registered as a 503B facility and still failed FDA's 503B conditions. Licensing lowers risk but does not remove it. Ask any provider whether the pharmacy is 503A or 503B and whether finished-product endotoxin testing is done.
Measured prescribes compounded subcutaneous NAD+ five days per week, cash-pay from $159/mo as of September 4, 2026, with provider screening, a state-licensed pharmacy, a registered dietitian and a plain account of the evidence before you pay.

Does NAD+ injection actually work?

Nobody knows yet, because nobody has run the trial. No published study has tested injected NAD+ for energy, focus or aging in healthy adults. The pills have been tested and mostly came up neutral. The shots have not been tested at all.

The trials that do exist tell you three things. Oral precursors like NR and NMN raise blood NAD+ in randomized trials. A 6-hour intravenous infusion of 750 mg caused no adverse events in the 2019 pilot in healthy adults. And in a randomized trial of 180 heart-failure patients, intravenous NAD+ improved heart function more than placebo, so the molecule does something measurable in the body at the right dose.

What is missing is the trial you care about. A 2026 PRISMA-guided systematic review of 33 human NAD+ studies found no outcome trials of intravenous or intramuscular NAD+ for wellness, and no efficacy trial of subcutaneous NAD+, the shot you take at home. Clinics started selling it before researchers tested it.

That includes Measured. We prescribe compounded NAD+ by subcutaneous injection, and you should hear the state of the evidence from us before you pay.

The harm, by contrast, is documented. The NAD+ injuries FDA has recorded came from endotoxin-contaminated compounded vials. In the most serious case, the compounder released the lot with no finished-product testing, and FDA later found the firm, by then registered as a 503B outsourcing facility, was not meeting 503B conditions. You cannot remove that risk, but you can ask who made your vial and whether anyone tested it, and a provider who dodges the question has answered it.

What NAD+ does in your body

NAD+ (nicotinamide adenine dinucleotide) carries electrons in the reactions that turn glucose and fat into ATP, the energy your cells run on. It also fuels sirtuins and PARPs, the enzyme families that repair DNA and regulate inflammation. A 2021 review in Nature Reviews Molecular Cell Biology explains why researchers treat NAD+ as a lever on aging biology.

The biology is why so many trials of precursors exist. The open question is whether raising NAD+ from outside changes how a healthy person feels.

"NAD+ injection" means three different things

Subcutaneous or intramuscular self-injection. Small, frequent shots at home. Telehealth companies, including Measured, prescribe this form.
Intravenous infusion. A clinic drip over hours. The main study in healthy adults used 750 mg NAD+ in saline over 6 hours.
Oral precursors. NR and NMN capsules, which are not NAD+ itself. A 2026 study by Nestle researchers proposed that NR and NMN raise systemic NAD+ after gut bacteria convert them to nicotinic acid.

Evidence from one form does not transfer to another. A null result for pills is not a verdict on shots, and a positive result for IV in cardiac patients is not a verdict on a subcutaneous shot in a healthy adult.

What has been tested in humans?

Route	Studied in	Result
Subcutaneous or intramuscular	No published efficacy trial yet.	The at-home route has not been put to a controlled test.
Intravenous	A 2019 pilot of 11 healthy men aged 30 to 55 (Grant et al.); a randomized trial of 180 adults with heart failure, published online September 2025 and in print 2026 (Yu et al.).	Grant 2019 measured plasma and urine metabolites; no adverse events during the 6-hour infusion. Yu gave intravenous NAD+ 10 mg/day or placebo for 7 days to cardiac patients and met its primary endpoint.
Oral NR and NMN	Most of the 33 human studies in the 2026 review.	Raised circulating NAD-related metabolites in trial after trial and were well tolerated over weeks to months. Functional effects were mixed and often null.

Two cautions on the intravenous row. The 2019 authors state that their 750 mg dose came from what infusion clinics already use, and one author is medical director of the wellness center where the infusions were given. The heart-failure result says nothing about a healthy adult injecting NAD+ for energy. A 2026 critical review concluded that intravenous longevity therapy should be regarded as experimental, and we agree, which is why a provider conversation comes before a prescription at Measured.

Do NAD+ injections work for energy, focus, aging, or weight?

Energy and fatigue

Verdict: untested for shots, mixed for pills. No trial has measured energy or fatigue after injected NAD+. Anything you read about it online is testimony.

The closest controlled data come from capsules. In a 60-day randomized trial of 80 healthy middle-aged adults (Yi et al., 2023), six-minute walking distance improved more on 300, 600 or 900 mg NMN daily than on placebo. Some authors worked for the manufacturer, and no independent group has reproduced the result. A 2025 meta-analysis found that current evidence does not support NMN or NR for preserving muscle mass and function in adults over 60.

Energy is the outcome most in need of a proper trial.

Cognition and focus

Verdict: pills raised blood NAD+ and cognition did not move; shots are untested. Two randomized trials gave oral NR to older adults with mild cognitive impairment. In a 2024 pilot of 20 adults, blood NAD+ rose 2.6-fold and cognitive scores held steady. In a 2026 phase-II pilot with 42 completers, blood NAD+ doubled with no change in cognition, cerebral blood flow or blood pressure.

Both trials enrolled people who already had impairment. No trial has tested any form of NAD+ in healthy adults with brain fog, which is the group most people asking this question belong to.

Aging and longevity

Verdict: the premise is shakier than the marketing, and the outcome is untested. The pitch assumes NAD+ falls with age. In tissue, it does: a 2012 study of 49 skin samples found NAD+ fell with age, and a 2015 MR study of 17 people saw the same in the brain, though a larger 2020 replication found only a small, non-significant change.

In blood, it mostly does not. A 2022 cohort of 1,518 adults found no significant change across age groups, with a modest decline only in men over 60. A 2026 Nature Metabolism study across seven cohorts found whole-blood NAD+ stable with age. A 2021 review in Nutrients concluded that evidence for an overall decline is limited and tissue-specific.

The 2026 systematic review's verdict on anti-aging outcomes: inconclusive. For a visual estimate of what the tissue studies imply at different ages, see The NAD+ Clock.

Weight and metabolism

Verdict: no. NAD+ is not a weight-loss treatment, and Measured does not sell it as one. A 2026 meta-analysis of 15 randomized trials of oral NMN found no significant effect on body weight, BMI, fasting glucose, HbA1c, lipids or systolic blood pressure. A 12-week trial of NR 1000 mg twice daily in 40 obese, insulin-resistant men did not improve insulin sensitivity or body composition.

If weight is your goal, GLP-1 medications have the trial evidence NAD+ lacks. See What is a GLP-1 medication and how does it work for weight loss?

Addiction and withdrawal

No study reviewed here tested NAD+ for addiction or withdrawal, so this article makes no claim about it. For the GLP-1 side of that question, see Can GLP-1 Medications Treat Addiction?

Are NAD+ injections safe, and are they FDA approved?

No NAD+ injection is FDA-approved, from anyone. FDA states that compounded drugs are not FDA-approved and that it does not verify their safety, effectiveness or quality before marketing. As of May 14, 2026, FDA lists NAD under 503A Category 1, meaning the substance is under evaluation. In a January 20, 2026 warning letter, FDA stated that products compounded with NAD+ are not eligible for section 503B exemptions because NAD+ is not on the 503B bulks list.

For you, that means no federal quality check exists on any NAD+ injection. The prescriber and the pharmacy are the check.

Contamination is the documented harm. That warning letter reports three patients who developed low blood pressure, uncontrollable shaking, shivers and body aches during or after a compounded NAD+ product and were sent to the emergency room. An unopened vial from the same lot contained bacterial endotoxins at 3,360 EU/mL. In an October 30, 2024 notice, FDA said it had received reports of severe chills, shaking, vomiting and fatigue after NAD+ injectables, consistent with excessive endotoxins, and that some compounders were using food-grade NAD+ unsuitable for sterile products.

FDA attributes these reactions to contamination rather than to NAD+ itself, though the reports do not rule the molecule out. The letter states that GenoGenix released the lot without any finished-product testing, that it registered as a 503B outsourcing facility in February 2025, and that at inspection it was not meeting 503B conditions. It does not say when the lot was made or shipped. Registration is a starting point; the questions below are the check.

Long-term data do not exist yet. Oral NR and NMN were well tolerated over weeks to months in the trials covered by the 2026 review. A 2020 benefit/risk analysis found a limited acute toxicity profile for NAD+ precursors and listed theoretical risks of raising NAD+ long term, including tumorigenesis and promotion of cellular senescence. No human study has observed those outcomes. They are why Measured's intake excludes people with active or prior cancer.

Three red flags. Vials sold online as "research grade" or "not for human use" with no prescription. Walk-in infusion services where no licensed prescriber evaluates you. Products whose pharmacy, ingredient grade and testing you cannot identify.

Three questions to ask any provider. Is the pharmacy a 503A pharmacy or a 503B outsourcing facility? (FDA holds 503B facilities to CGMP requirements; 503A pharmacies are exempt.) Is finished-product endotoxin testing done before release? Is the ingredient pharmaceutical grade? A provider who cannot answer has told you what you need to know.

What changes when a clinician prescribes NAD+?

A prescriber does not change what the trials say. A prescriber changes who checks you before you inject, who makes the vial, and who answers for what is in it.

At Measured, a licensed provider reviews your health history and screens for the conditions where NAD+ is not appropriate. Independent, state-licensed pharmacies fill the prescription. A registered dietitian is part of your plan. Before you start, you are told that NAD+ injections are compounded, not FDA-approved, and untested in outcome trials.

Route and schedule. Subcutaneous injection, five days per week. Small, steady doses at home rather than a clinic drip.
Cost. As of September 4, 2026, Measured lists NAD+ Injection from $159/mo, marked "No insurance required" and "Medication included." No prior authorization, no claims, and you can cancel anytime; cancellation takes effect at the end of the billing period.
How long to give it. Our providers suggest 4 to 12 weeks of consistent use before judging whether NAD+ is doing anything for your energy, focus or recovery. No trial has measured a timeline, so that window is clinical judgment, not a result you should expect.
Who is screened out. Pregnancy or breastfeeding, active or prior cancer, and kidney disease without specialist clearance (source). These are Measured's own prescribing exclusions, since compounded drugs carry no FDA labeling.
Side effects listed. Flushing, headache, stomach upset and injection-site reactions, usually mild and temporary (product page). No trial of injected NAD+ has published a side-effect profile, so treat that list as patient experience.
Disclosure. Compounded medications are not reviewed or approved by the FDA for safety or effectiveness. Measured does not itself compound or dispense medications; any prescription is issued solely at the independent clinical judgment of a licensed healthcare provider and filled by independent, state-licensed pharmacies.

Measured does not name its pharmacy partners publicly. Ask your care team about the pharmacy or the testing behind your prescription and they will tell you.

Should you try NAD+?

If you want a proven treatment, this is not one, and we would rather lose the sale than tell you otherwise. If you want to try something with plausible biology and no adverse events in the short trials that exist, you can do that with your eyes open.

Do it with a provider who screens you first, a pharmacy you can question, and a plain account of the evidence. That is what Measured offers. It starts with a provider review, and you decide from there.

What would change this answer

The trial that would settle it is a randomized, placebo-controlled trial of subcutaneous or intramuscular NAD+ in healthy adults, with functional endpoints such as a validated fatigue scale, a cognitive battery or physical performance, run long enough to cover the 4-to-12-week window providers suggest. None has been published. The 2026 systematic review closed its search in October 2025, so newer results may appear. We will update this article within 6 to 12 months, or sooner if that trial lands.

Frequently asked questions

Is NAD+ injection FDA approved?+

No, and no NAD+ injection on the market is. Injected NAD+ is a compounded product, and FDA states that compounded drugs are not FDA-approved and that it does not verify their safety, effectiveness or quality before they are marketed. As of May 14, 2026, FDA lists NAD under 503A Category 1, meaning it is under evaluation. A January 20, 2026 FDA warning letter stated that products compounded with NAD+ are not eligible for section 503B exemptions because NAD+ is not on the 503B bulks list. What this means for you: the prescriber and pharmacy behind the vial are the only quality checks that exist, so choose them carefully.

NAD+ shots vs NMN pills: which has more evidence?+

Pills have more studies. The 2026 systematic review identified 33 human intervention studies, 28 of them randomized, almost all of oral precursors. They consistently raised blood NAD+, but functional benefits were mixed and often null. Injected NAD+ delivers the molecule itself rather than a precursor, but it has not yet been tested in a published wellness outcome trial. The pills have been tested and mostly came up neutral; the shots have not been tested.

How long before you notice anything from NAD+ injections?+

No published trial has measured a timeline for injected NAD+, so nobody can promise you one. Our providers suggest giving it 4 to 12 weeks of consistent use before deciding whether it is doing anything for your energy, focus or recovery, and they check in with you along the way. If you feel nothing by then, that is useful information too. A Measured provider can help you set realistic expectations before you start.

Are NAD+ injections safe?+

The short-term data are reassuring and the long-term data do not yet exist. In the 2019 intravenous pilot, no adverse events were seen during a 6-hour infusion of 750 mg. The harms FDA has documented came from contaminated compounded products: a January 20, 2026 warning letter describes three patients sent to the emergency room after a product whose vial contained excessive endotoxins. Measured's product page lists flushing, headache, stomach upset and injection-site reactions as usually mild side effects, and its intake excludes pregnancy, breastfeeding, active or prior cancer, and kidney disease without specialist clearance. Those are Measured's prescribing rules, not FDA labeling.

Is it safe to buy NAD+ injections online without a prescription?+

No. The NAD+ injuries FDA has documented involved compounded products with excessive endotoxins or food-grade ingredients, and a product sold without a prescription sits outside the rules meant to prevent exactly that. You cannot verify who made it, what grade of ingredient was used, or whether it was tested. A prescriber and a state-licensed pharmacy are the only way to know what is in the vial.

Does insurance cover NAD+ injections?+

No, and Measured is built for that. NAD+ is offered cash-pay, marked 'No insurance required' and 'Medication included,' from $159/mo as of September 4, 2026, with no prior authorization or claims to file. GLP-1 medications are a different situation, with plan-dependent coverage and appeals; see Does insurance cover GLP-1 weight loss medications? (/blog/does-insurance-cover-glp-1-weight-loss-medications).

How much do NAD+ injections cost per month?+

Measured lists NAD+ Injection from $159/mo as of September 4, 2026, marked 'No insurance required' and 'Medication included.' That price covers the medication, the prescriber review and the care team. This article does not price clinic infusions or products sold without a prescription. Before you compare prices, ask whether the vial comes from a state-licensed pharmacy you can question.

How often do you inject NAD+, and is there a proven dose?+

At Measured, NAD+ is given by subcutaneous injection five days per week, a schedule designed for steady, small doses at home rather than a single large infusion. No published trial establishes an effective dose for subcutaneous NAD+. The only intravenous study in healthy adults used 750 mg over 6 hours, a dose the authors describe as derived from clinic practice. Your Measured provider sets your plan based on your history, not a generic chart.

What are the side effects of NAD+ injections?+

Measured's product page lists flushing, headache, stomach upset and injection-site reactions, described as usually mild and temporary. That reflects patient experience; no trial of injected NAD+ has published a side-effect profile. Separately, FDA has received reports of severe chills, shaking, vomiting and fatigue after NAD+ injectable products, which it says are consistent with excessive endotoxins from contaminated compounded products. Long-term safety data do not yet exist.

NAD+ injection vs IV infusion: is one better?+

No head-to-head trial exists. Intravenous NAD+ has been studied for blood levels and tolerability in healthy adults and in one heart-failure trial. Subcutaneous NAD+, the at-home shot, has no published efficacy trial yet. The practical difference is a clinic drip over hours versus small, frequent doses at home from $159/mo with a provider on call.

Do NAD+ injections help with weight loss?+

NAD+ is not a weight-loss treatment, and we do not sell it as one. A 2026 meta-analysis of 15 randomized trials of oral NMN found no significant effect on body weight, BMI, fasting glucose, HbA1c or lipids, and no trial has tested injected NAD+ for weight. If weight is your goal, GLP-1 medications have the evidence; see What is a GLP-1 medication and how does it work for weight loss? (/blog/what-is-a-glp-1-medication-and-how-does-it-work-for-weight-loss).

Can NAD+ injections cause cancer?+

No human data show that they do. A 2020 benefit/risk analysis of NAD+ precursors found a limited acute toxicity profile but noted that long-term trials were still nascent and listed tumorigenesis among the theoretical risks of raising NAD+ levels. No human study has observed it. Measured's intake excludes people with active or prior cancer for that reason.

Does NAD+ help with alcohol addiction or withdrawal?+

No study reviewed for this article tested NAD+ for addiction or withdrawal, so we make no claim either way. Clinics that promise it are working ahead of the evidence. The GLP-1 side of that question has real research behind it; see Can GLP-1 medications treat addiction? (/blog/can-glp-1-medications-treat-addiction).