For people like me, antihistamines have a paradoxical effect - they wire me up! When I was forced off my 1 mg of Klonopin at bedtime after 12 years, leaving me a raving insomniac, I was first offered Vistoril, an antihistamine and when that didn't work, Remeron, which is an tricyclic antidepressant that acts like an antihistamine in your brain. It did not work either. A neurologist/sleep specialist prescribed 2 mg Lunesta and it works to help me sleep, but I am having night sweats again (65 so this is not menopause) which wake me frequently. At least I can go back to sleep, but it is not uninterrupted. Also some nights, I have leg cramps that get me out of bed. But some sleep is better than no sleep, and I am calmer when I wake up.