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Putting NAD+ in a vein doesn't prove it helps.

# Putting NAD+ in a vein doesn't prove it helps.

![A resident reaches up to peg an ordinary white shirt to a rooftop clothesline.](/roofletters-f00b3c250552/hanging-shirt.webp)

Direct delivery sounds convincing. We still want to know what happens next, whether the person benefits and what risks come with it.

## Where does the infused NAD+ go?

In a small [six-hour infusion study in healthy men](https://pubmed.ncbi.nlm.nih.gov/31572171/), NAD+ in plasma, the liquid part of blood, didn't rise detectably during the first two hours. Researchers also found breakdown products in urine. The body was processing the NAD+, rather than simply keeping it untouched.

That helps explain what happens during delivery. Lasting relief from fatigue, clearer thinking and a longer life weren't established here. Those outcomes weren't what this pilot was designed to test. An oral NR or NMN study can't fill that gap either: those are ingredients for making NAD+, taken by a different route.[a](/nad-injections#nal-note-a)

## The preparation matters

People receiving NAD+ infusions have reported flushing, nausea and discomfort in the chest or abdomen. Contamination is another concern. A compounded NAD+ injection has been recalled for elevated bacterial endotoxin, material from bacteria that can cause harmful reactions. A familiar molecule can still arrive in an unsafe preparation.

[Compounded medicines aren't FDA-approved](https://www.fda.gov/drugs/human-drug-compounding/understanding-risks-compounded-drugs). For these preparations, FDA hasn't checked quality, safety and effectiveness ahead of marketing. A prescription means a clinician has made a treatment decision; it doesn't mean the medicine has passed FDA approval.[b](/nad-injections#nal-note-b)

## A request can end with no prescription

Promise Peptides offers prescription care for compounded NAD+, with a licensed U.S. clinician reviewing each request and deciding whether it fits. Some requests may be declined. Care is for U.S. patients only, and availability depends on the state and treatment.

For telehealth, the clinician needs [the right licence or permission where the patient is located](https://telehealth.hhs.gov/licensure/getting-started-licensure). An online appointment doesn't remove that requirement. This guide can't assess eligibility or arrange care.

## What would make it worthwhile?

A useful discussion stays close to the problem you want help with. What evidence connects this exact preparation to it? What change would count as helpful? How would harms be checked, and when would treatment stop?

The [review of human precursor studies](https://pubmed.ncbi.nlm.nih.gov/41083806/) finds benefits less clear than blood-level changes. It doesn't establish the benefits of injections. Any treatment plan, including administration instructions, needs the treating clinician's assessment of the person and the actual medicine.

## A closer look

Extra context, if you want to stay with a thought.

### The route changes the question

An infusion goes into a vein. A subcutaneous injection goes under the skin. Evidence for one doesn't establish the benefits or safety of the other.

[Return to a in the essay](/nad-injections#nal-call-a)

### What compounding means

[FDA describes compounding](https://www.fda.gov/drugs/human-drug-compounding/compounding-and-fda-questions-and-answers) as preparing a medicine for a patient's needs. That preparation process doesn't supply FDA approval.

[Return to b in the essay](/nad-injections#nal-call-b)

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