Can't help you with the meds, but grew up in the Middle East and Africa minus reliable power ...
I think I've said elsewhere, but if you do have power, plastic drink bottles filled with water and deep frozen, then put in front of a fan. It's like a DIY air con.
Those packs you use in cool boxes, put one under your pillow on a hot night.
Hang wet cloth at open doors and windows, not sure how it works, but sort of absorbs some of the heat, like a reverse storage heater.
It's ok to drink rehydration salts (like the ones you get for after d&v) if you're worried about sweating out too much.
You can also put a stone in the freezer and, once cool, get it out and use it on forehead / grip in hand / pass over nape of neck. I find this helps me with panic asw.
Eat late, like 9pm.
Get in the sea - this is literally my plan.