I take the dewormer right before going to bed so I can take it on somewhat an empty stomach. That way if the parasites are hungry, this is what they will eat! In the case of taking it at bedtime, I don't eat again until breakfast. I do take two of the lower bowel balance capsules at the same time as taking the dewormer.
I also take the dewormer first thing upon arising, along with one lower bowel balance capsule. When I eat breakfast usually depends upon my schedule. Some morning, I have to eat within 5-10 minutes of taking it as I have to leave. Other mornings, I get busy doing other things and wait an hour or more.
As I take the dewormer right before heading up to bed, I can say it definitely does not prevent me from sleeping. I have slept pretty soundly and usually go to sleep within 15-30 minutes of taking it at night.