I don't wanna advise you on which medication to use, however if I was you I would use a sedative that actually has been studied for hppd, I don't know if that one has but you should look it up. There are many sedatives out there, some are better for hppd than others. I know clonidine is a sedative/antihypertensive, so it will make you tired and lower your blood pressure also said to have helped lower hppd symptoms and anxiety. Be careful if your bp is already low though. It works on a2adren receptors so it basically lowers your adrenaline production, which You could imagine how that could make you feel.