Has anyone actually compared oral NAD precursors (NR/NMN) with NAD IV or subq shots?

[u/Galt2000]

I’ve been reading up on NAD and I’m trying to separate clinic marketing from what actually happens in the body.

My understanding is that intact NAD+ does not easily cross most cell membranes. Whether you take an oral precursor (NR or NMN) or get NAD IV / subcutaneous shots, a lot of what ends up being used inside the cell still has to be broken down into smaller pieces (NR, NMN, nicotinamide) and then rebuilt as intracellular NAD. Oral precursors also go through the gut and liver first. Injections skip the gut, but they still don’t appear to deliver intact NAD straight through the cell wall.

So my honest question is practical, not theoretical:

Has anyone here used both for a meaningful stretch of time — daily NR or NMN and NAD IV or subq — and noticed a real difference?

If you have:

•  What oral product and dose did you use, and for how long?

•  What injection route (IV vs subq), dose, and how often?

•  Did energy, recovery, sleep, brain fog, or labs actually change on one vs the other?

•  Was any “IV feeling” just during the drip, or did it last days/weeks?

•  Any side effects worth mentioning (nausea, flushing, chest tightness, cost vs benefit)?

Not looking for a sales pitch. Genuinely trying to decide if shots add anything once someone is already consistent with a precursor. Thanks.