

I am not sure about kitty litter, but I swear by Numatic, known for the Henry model. Due to its design, it will not lose suction power as much as regular vacuum cleaners as the dust bag fills up. It is extremely repairable and it has great reach (long cable, long hose).
There are brands that sell melatonine that will start working after some time. My son gets a blend of fast and slow release melatonin, as he had the problem you describe: fall asleep somewhat normally and be wide awake in the middle of the night.