What are the side effects of NAD+ injections?

This page reports what published studies, reviews and official sources say. It does not tell you whether NAD+ is right or wrong for you, and nothing here is a recommendation. Where evidence is missing, we say so.

What side effects are reported with NAD+ injections?

We found no published human study that reports side effects of NAD+ given by subcutaneous injection, so for that route the honest answer is that it is not known. ⁵

Our searches of PubMed on 11 November 2026 for subcutaneous NAD+ in humans returned no results, and a search for intramuscular NAD+ trials returned nothing relevant. ⁵

A 2026 systematic review found no outcomes trials of intravenous or intramuscular NAD+ itself for ageing-related or wellness uses. ⁵

That review looked at benefits rather than side effects, but with no trials there is also very little to say about how people respond.

Any needle can leave a mark at the site. The NHS says that after a blood test you may get some bruising or swelling that should go away after a few days, although that page describes blood tests and not NAD+. ⁷

You can read more about NAD+ injections on their own page.

What side effects are reported with NAD+ IV infusions?

A 2026 review summarises the short-term effects reported with IV NAD+ as nausea, abdominal discomfort, flushing, cramping, chest pressure and infusion-related intolerance, particularly at faster infusion rates. ²

That summary rests on a handful of small studies and gives no incidence rates. ²

The table sets out what each source reports, and how far you can lean on it.

Source	Who and what	What was reported	Limits
Alangari et al. 2026, review 2	Summary of small studies of IV NAD+	Nausea, abdominal discomfort, flushing, cramping, chest pressure, infusion-related intolerance, particularly at faster rates	Based on a few small studies; no incidence rates
Reyna et al. 2026 3	Retrospective review of records from a commercial setting: IV NAD+ 500 mg on four consecutive days (6 people) against IV nicotinamide riboside (8 people), 30-day follow-up	NAD+ group: moderate to severe gastrointestinal symptoms, increased heart rate and chest pressure during infusions, which resolved when the infusion finished. Nicotinamide riboside group: minor tingling and mild cramping	No control group; very small; commercial setting
Grant et al. 2019 4	8 healthy men given 750 mg NAD+ IV over 6 hours, 3 given saline	No adverse events observed in either group	11 people in total; a slow 6-hour infusion says little about shorter infusions
Braidy 2018, as described in the 2026 review 2	8 people given 1,000 mg a day for 6 days	Mild flushing, transient nausea and transient chest discomfort in some	Small and uncontrolled; the review says to read it cautiously; we did not review the original

Does the infusion speed seem to matter?

Both 2026 papers point towards speed mattering, but neither can prove it.

The review says rapid infusion can sometimes cause discomfort, flushing or nausea, according to anecdotal reports from wellness settings where many practitioners prefer slow infusions of 2 to 4 hours. ²

The review itself calls this anecdotal, so it should not be read as an established finding. ²

In the Reyna review the NAD+ infusions took longer than the nicotinamide riboside ones (a mean of 97 minutes against 37), and the NAD+ group still reported the more marked symptoms. ³

With six people in that group and no control, it cannot show what drove the symptoms.

The 2026 review also notes that infusion rate and diluent are not standardised, which means the speed at one clinic may differ from the speed in a study. ²

For more on how drips work, see NAD+ IV therapy.

What general risks come with an IV line?

Any IV line carries some risk of its own, whatever is in the bag. A patient leaflet from an NHS trust says that having a cannula inserted can lead to a variety of infections, and that the most common complication is phlebitis, an inflamed vein with swelling and redness around the site. ⁶

That leaflet is general information about cannulas, not about NAD+.

Are NAD+ injections safe?

The evidence we reviewed is too limited to give a general yes or no.

The 2026 narrative review concludes that “Current evidence regarding IV NAD+ therapy remains preliminary and insufficient to support routine clinical or wellness use.” ¹

We found no registry or surveillance data on how often side effects occur in clinics, only small series of between 6 and 11 people.

The table separates what we found from what we did not.

Question	What we found
Are short-term effects reported with IV NAD+?	Yes, in small studies and a 2026 review 2, 3
How often do they happen?	Not known: no incidence data found
Side effects of subcutaneous NAD+ in humans?	No human studies found 5
Side effects of intramuscular NAD+?	No outcomes trials found; little else known 5
Long-term safety of repeated use?	Not known: reviews say data are lacking 1
NHS or NICE guidance on NAD+?	None found in searches on 11 November 2026 10

Is there long-term safety data?

No: the 2026 review states that “long-term safety data are lacking”. ¹

Its full wording is “Reported adverse effects include nausea, cramping, flushing, and chest discomfort, while long-term safety data are lacking.” ¹

The review also notes that theoretical concerns have been raised about interactions with cell growth and malignancy biology. ²

It cites no human evidence of harm, and we mention the point only because it shows how much is still unknown, not because we have seen a risk. ²

The review adds that animal data on a related compound cannot rule out long-term risk in people receiving repeated IV doses. ²

Studies are under way. One registered randomised trial compares injected nicotinamide riboside, injected NAD+ and placebo in healthy adults, but it was still recruiting and had posted no results when we checked on 11 November 2026. ¹¹

Who should take medical advice first?

We cannot tell you who should or should not have NAD+, and the sources we reviewed do not either.

The Nursing and Midwifery Council says prescribers have a professional responsibility to supply medicines only where clinically appropriate and where they know enough about the person’s health and their full medical and prescribing history. ⁸

The advertising code’s rule 12.3 also expects those offering invasive treatments to be able to say who supervises and administers them, and to encourage people to take independent medical advice. ⁹

Searches of the NHS website and the NICE website on 11 November 2026 returned no results for NAD+, so there is no national guidance to point to on who it may suit. ¹⁰

It may help to read how to check a clinic before you decide, and to ask your GP or another registered prescriber about your own health first.

What should I do if I have a reaction?

We cannot advise on symptoms; for urgent help the NHS points you to 999 in a life-threatening emergency and to NHS 111 if you are not sure.

The NHS says: “999 is for life-threatening emergencies like serious road traffic accidents, strokes and heart attacks.” ¹²

It also says to get help from NHS 111 if you are not sure whether you need to call 999. ¹²

NHS 111 says it can help if you think you need medical help right now. ¹³

That service is for England. The NHS lists NHS 24 111 for Scotland, NHS 111 Wales for Wales and nidirect for Northern Ireland. ¹³

Chest pressure and a faster heart rate were among the effects reported in the Reyna review. ³

We cannot tell you whether any symptom you have is serious, which is why this page points you to NHS services and not to a list of warning signs of our own.

How do I report a side effect in the UK?

The MHRA’s Yellow Card scheme says anyone can report an issue with a medicine, vaccine, medical device, blood product or e-cigarette. ¹⁴

We could not confirm from the page whether a particular NAD+ product falls within the scheme, because we found no public MHRA statement on how NAD+ is classified, as explained in our guide to how NAD+ is regulated.

You can still tell the clinic what happened, and it may be worth letting your GP know.

If you have a concern about how a clinic described a product, that is a matter for the advertising regulator, and the legal status page explains where to take it.

How reliable is the evidence on this page?

It is limited: the studies cited here are small, and several are retrospective or uncontrolled.

One of them compares NAD+ with a different precursor, nicotinamide riboside, and the 2026 reviews are the main source for what is known overall. For the basics, see what NAD+ is. The numbered sources are listed at the end of the page.

This page is general information, not medical advice. Speak to your GP or a registered prescriber before making decisions about your health, and see our medical disclaimer.