An old useful drug, with a few uses, and one caution
Chlorpheniramine is an old antihistamine with some sedative properties. Compared to Benadryl (generic: diphenhydramine), it doesn't last as long as a sedative, which makes it somewhat superior as a sleep medicine in my opinion - one wakes up alert rather than still a bit sedated.
As an antihistamine, not particularly strong, but worth trying. Don't take it and drive.
It may be useful as an antidepressant and for panic disorder. Google "PMID 16413139" for the citation on Pubmed. It is an SSRI, but has never been systematically evaluated compared to the newer ones like Zoloft or Celexa.
Lastly, the caution: There is some recent concern that long-term use of anti-cholinergic medications may be associated with an increase in Alzheimer's disease. Therefore I would not use this as a regular sleep medication, but rather as an occasional means of getting a good sleep rhythm started again. Other anticholinergic medications include diphenhydramine (Benadryl) and Oxybutinin (Ditropan). Cholinergic nerve endings are involved in cognitive functioning, so it's not surprising that drugs that interfere this way might have long-term adverse effects.
Lastly, pretty inexpensive - I've even seen it the dollar store for 1-2 cents per tablet.
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