Curious why Doxylamine is considered more efficacious for sleep over Diphed? I usually use benadryl as a sleep aid if I really need help. Always interesting info from you @LumeticFor sleep, I don't know that I would put a lot of faith (long term) in Kava. Kava is said to be a relaxant, and perhaps intoxicant is a better descriptor, sort of like ethanol. Responses, even within an individual, can vary. Set and setting with any drug is important, and whatever the human is bringing to the table at that moment (stress, happiness, anger) will affect drug response.
For any one looking for something to try, Doxylamine Succinate, it is an OTC sedating antihistamine, although not all pharmacy chains carry either a branded or generic product. Diphenhydramine is similarly a sedating antihistamine and not the same in terms of sleep. Do not let the Pharmacist talk you into 'this' when you want 'that'.