Immunocal makes glutathione in your cells, and glutathione restores the mitochondria or the powerhouse of your cells for energy.
So for some, taking Immunocal at bedtime may give them energy, thus preventing sleep. For others, they can take Immunocal any time day or night, and still sleep well that night.
The best way to find out is to take some Immunocal before bed and see what it does in your case. If you don't want to risk losing a night of sleep, just take Immunocal every morning, like most do, and you'll be good to go!
You can grab a box for yourself here.