@clynnp Just a heads up: This morning, I received a PM from someone that is 1 week into the NMN and is more tired. Sure enough, if the dosing/timing is not optimum, this can be a side effect. I did read online that it typically clears up in 1-3 weeks, but unsure if that's always the case. I've always been hypersensitive to medications-so probably supplements as well. I started with 150 mg versus the recommended 300 mg and did not experience any negative symptoms. Last week I increased the dose to the 300 mg and have noticed I am sleeping longer and have mild heaviness to my legs (not enough to keep me off the treadmill), so I'm back on the 150 mg as of today. The silver lining is, it must be doing something if the increase in dosage initiated a side effect that I was unaware of. It's also best to take morning or mid-morning.