Why does antihistamine make you sleepy?

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Tags

1. #results
2. #typically
3. #receptors
4. #allergy
5. #carrying
6. #histamines
7. #brain
8. #compounds
9. #functions
10. #action
11. #preventing
12. #antihistamines
13. #drowsiness
14. #disruption
15. #symptoms
16. #their
17. #blocking
18. #attachment