doxepin

In very low doses, doxepin acts against the H1 to promote sleep.

One example: Doxepin is an old antidepressant that is extremely cheap.

Low-dose doxepin (3mg) has also helped, but I find that I have to take breaks from it, because it stops working after a while.

I don't think it is the case that diphenhydramine (Benadryl) reduces REM sleep (or other antihistamines like low dose doxepin), at least not by much.

To avoid the upcharges of low dose doxepin, I am prescribed the high dose version, which I have to break the capsules to administer about 5 to 10 mg.

During that month I took doxepin it gradually had less effect but I generally got better sleep than usual and the tiredness felt different from the sleep deprevation tiredness.

On the other side, low dose doxepin has a long half life and completely wipes me out during the day (although so do some second generation antihistamines so it is possible there is some unusal indirect effect).

First-generation antihistamines might be better as a "get to sleep soon" drug, either diphenhydramine or, I've heard but haven't tried yet, ultra low dose doxepin (.5 to 4mg liquid form, works just as an antihistamine at that dose but has a longer half-life).

Doxepin is prescribed as an antidepressant in large doses, one of the most potent H1 histamine antagonists known.