I don't know about NMN spray, but maybe you guys are mixing it too strong?
I have been taking the NAD+ spray from Alivebynature and really liking it. There is no burning or any unpleasant feeling at all. I am taking it instead of the NAD+ powder more and more, as it clears my head better. Pretty good cost savings too, as you don't need nearly as much.
They actually show quite a bit of research on the product page that shows intranasal is very effective for brain disorders (in mice).
Also, some research showing NAD does enter at least some tissues intact. cut and past below:
Neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s diseases, frontotemporal dementia or amyotrophic lateral sclerosis all belong to the group of protein misfolding neurodegenerative diseases, which induce neuronal death by NAD+ starvation.
Loss of blood flow due to traumatic brain injury or stroke also results in NAD+ starvation and neuronal death.
Increasing evidence has supported the hypothesis that PARP-1 induces cell death by depleting intracellular NAD+. We observed that intranasal NAD+ delivery significantly increased NAD+ contents in the brains.
Intranasal delivery with 10 mg / kg NAD+ at 2 hours after ischemic onset profoundly decreased infarct
The NAD+ administration also significantly attenuated ischemia-induced neurological deficits.
NAD+ metabolism is a new target for treating brain ischemia
NAD+ administration may be a novel strategy for decreasing brain damage in cerebral ischemia and possibly other PARP-1-associated neurological diseases.
Our results provide the first in vivo evidence that NAD+ administration can profoundly decrease brain damage
It is noteworthy that NAD+ can reduce infarct formation by up to 86 % even when administered at 2 hrs after ischemic onset.
the protective effect of NAD+ could be one of the most profound effects ever reported.
intranasal administration with nicotinamide at 10 mg / kg can not affect ischemic brain damage, in contrast to the profound protective effects of 10 mg / kg NAD+.
The present study demonstrates that intranasally-administered NAD+ increases hippocampal NAD+ levels and reduces TBI-induced neuronal death in the hippocampus.
Intraperitoneal injection of the same NAD+ concentration that we used for intranasal administration showed no neuroprotective effects on TBI-induced neuronal death.
Compared with NAD+-treated rats, nicotinamide treatment showed no protective effects against TBI-induced neuronal death
We show that abnormal autophagy activation and neuronal demise is due to severe, neuron-specific, nicotinamide adenine dinucleotide (NAD+) depletion.
Toxic prion protein-exposed neuronal cells exhibit dramatic reductions of intracellular NAD+ followed by decreased ATP production, and are completely rescued by treatment with NAD+
Intranasal NAD+ treatment of prion-infected sick mice significantly improves activity and delays motor impairment.
Our data demonstrate for the first time that a failure of NAD+ metabolism is the cause of neuronal ailing. Neuronal death can be rescued in vitro and in vivo by NAD+ replenishment.
Misfolded amyloidogenic protein can induce neuronal death by genuine NAD+ starvation and that ailing neurons can be completely rescued by NAD+ treatment
Our study shows that neuronal death induced by NAD+ depletion is reversible and that NAD+ replenishment mitigates neurodegeneration
We propose the development of NAD+ replenishment strategies for neuroprotection in prion diseases such as Alzheimer’s, Parkinson’s, and Huntington’s diseases, frontotemporal dementia or amyotrophic lateral sclerosis.