NAD+ injections: 'specific repair' claims vs. what trials show

What did @nursedoza actually say?

The core claim here is that NAD+ injections have a kind of biological GPS. According to the creator, a practicing clinician, NAD+ "goes exactly where it needs to go" after injection. Shoulder tingling after a shot? NAD+ is repairing your rotator cuff. Nausea? That's NAD+ fixing your gut. Sensation behind the left eye? The molecule made a beeline for an eye condition. The framing is that subjective feelings post-injection are diagnostic proof of targeted tissue repair.

To be fair, the creator is describing clinical observations, not a randomized trial. They're sharing patient anecdotes and interpreting them through a mechanistic lens. That's a normal thing clinicians do informally. The problem is that those interpretations are being stated as fact on a platform with 37,000 viewers.

Does the science back this up?

No. There is no credible pharmacokinetic evidence that NAD+ preferentially distributes to injured tissues after injection. This is not a close call. NAD+ is a small molecule that participates in metabolism across essentially every cell type in the body. After intravenous or intramuscular administration, distribution follows blood flow, tissue uptake kinetics, and enzymatic conversion, not injury signals.

What we do know is more modest. NAD+ precursors like nicotinamide riboside and NMN have shown some ability to raise systemic NAD+ levels in humans (Martens et al., 2018, Cell Metabolism; Yoshino et al., 2021, Science). Animal models suggest NAD+ repletion may support cellular repair pathways via sirtuins and PARP enzymes (Cantó et al., 2015, Cell Metabolism). But "supports cellular metabolism" is a very long way from "travels to your rotator cuff because it sensed an old injury." That second claim has no mechanistic basis and no supporting literature.

What did they get wrong (or right)?

Let's start with what's defensible. NAD+ does play a real role in DNA repair and mitochondrial function. Post-injection sensations, including nausea, are genuinely reported by patients and are worth tracking clinically. The creator is right that nausea is common with NAD+ infusions, though the actual explanation involves the rate of infusion triggering prostaglandin release, not targeted gut repair (Bhatt et al., 2023, Journal of Clinical Medicine).

What they got wrong is significant. The claim that tingling or sensation in a specific body part means NAD+ "went there" is a post hoc fallacy. Paresthesias after injection have multiple explanations, including vasodilation, nerve sensitivity, and placebo response. Interpreting a patient's tingling shoulder as NAD+ repairing a years-old rotator cuff tear is not clinical reasoning. It's storytelling. The eye example is the same pattern: a patient reports a sensation, the clinician assigns a repair narrative, and 37,000 people hear it as science.

What should you actually know?

NAD+ therapy is a genuinely interesting research area, and that makes the overclaiming worse, not better. There's real science worth following here. Studies in older adults show NAD+ precursor supplementation can raise circulating NAD+ levels and may improve some metabolic markers. There is preliminary human research on NAD+ in neurodegenerative conditions and aging. None of this translates to a molecule that self-navigates to your injured rotator cuff.

If you're considering NAD+ injections, the honest clinical picture is this: systemic NAD+ repletion may support cellular energy metabolism broadly. Sensations during or after infusion are real but are not a reliable map of where the molecule went or what it's fixing. Anecdote is not mechanism. A clinician's pattern recognition from thousands of injections is a starting point for a hypothesis, not evidence of targeted repair. Anyone offering NAD+ IV therapy should be able to explain what they're actually measuring to assess outcomes, because "the patient felt it in their shoulder" is not a measurable endpoint.