IV vs. IM NAD+ injections: what the pharmacology actually shows

What's this video probably claiming?

Based on the caption and creator context, @vitalithela is likely walking viewers through the pharmacokinetic differences between intramuscular and intravenous NAD+ delivery, probably arguing that one route produces superior bioavailability, faster cellular uptake, or more pronounced clinical effects. Creators in this space typically claim IV NAD+ saturates tissue faster, produces an immediate "energy" response, and bypasses first-pass metabolism in ways IM cannot replicate. Some go further, implying that the infusion-related side effects (flushing, chest tightness, nausea) are actually a sign of cellular repair happening in real time. That last claim is pharmacologically backwards. The discomfort is vasodilatory, not therapeutic. There is also likely some framing around NAD+ precursors like NMN or NR being inferior to injectable forms, which is a claim the current literature does not cleanly support.

What does the science actually show?

NAD+ does not cross cell membranes intact in meaningful quantities when given intravenously. Cells synthesize NAD+ internally from precursors, primarily via the salvage pathway using nicotinamide. Grozio et al. (2019, Nature Metabolism) showed that NMN is transported into cells via the Slc12a8 transporter, raising serious questions about whether exogenous NAD+ itself is the active agent regardless of delivery route. Trammell et al. (2016, Nature Communications) demonstrated that orally administered NR raised whole-blood NAD+ levels significantly in humans, complicating the "only IV works" narrative. IV NAD+ infusions do raise circulating NAD+ metabolites acutely, documented in small trials, but controlled human data comparing IM versus IV delivery on tissue-level NAD+ concentrations is essentially nonexistent in the published literature as of 2024. The pharmacokinetic "nerding out" this creator is doing is likely built on reasonable biochemistry extrapolated well beyond what clinical trials have confirmed.

Where does the social media noise diverge from clinical reality?

The biggest gap is between acute plasma NAD+ elevation and actual clinical outcomes. Creators conflate the two constantly. Raising circulating NAD+ is measurable. Whether that translates to meaningful mitochondrial function improvements, cognitive benefits, or longevity effects in healthy adults is a separate and largely unanswered question. Martens et al. (2023, Nature Aging) showed NMN supplementation at 600 mg/day improved muscle insulin sensitivity in older adults, but the effect sizes were modest. No equivalent IV versus IM trial exists with hard clinical endpoints. The side effect profile of IV NAD+ (flushing, palpitations, nausea during infusion) is routinely framed by wellness creators as detoxification or cellular activation. It is not. It reflects rapid vasodilation and likely mast cell involvement. Repackaging adverse effects as proof of efficacy is a pattern that should make any viewer skeptical. IM NAD+ avoids the infusion rate problem but introduces its own absorption variability depending on injection site and blood flow.

What should you actually know?

If you are considering NAD+ therapy through a telehealth platform, a few things are worth knowing before you commit. First, there is no peer-reviewed RCT directly comparing IV and IM NAD+ on clinical outcomes in humans. The mechanistic arguments are real but extrapolated. Second, oral NAD+ precursors (NR and NMN) have more human trial data than injected NAD+ does, which should give you pause about the hierarchy being implied. Third, IV infusions carry non-trivial procedural risks including infection, phlebitis, and cardiovascular stress during rapid infusion, which outpatient wellness settings are not always equipped to manage. Fourth, cost matters: IV NAD+ infusions frequently run $400 to $1,000 per session. The evidence base does not currently justify that premium over well-studied precursor supplementation for most people. Ask any provider recommending injectable NAD+ to show you the comparative pharmacokinetic data. Most cannot, because it largely does not exist yet.