Why does diphenhydramine make you sleepy?

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Tags

1. #chemical
2. #feeling
3. #central
4. #medication
5. #system
6. #drowsy
7. #symptoms
8. #blocking
9. #benadryl
10. #insta
11. #plays
12. #works
13. #nervous
14. #produced
15. #after
16. #wakefulness
17. #histamine
18. #hence
19. #allergy
20. #produces
21. #sleepy