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Histamine, antihistamines, and the central nervous system
1Departments of Medicine and Pediatrics, University of Tennessee, Memphis, Tennessee, USA. aac@allergymemphis.com
Allergy and Asthma Proceedings
|October 22, 2009
Summary
Histamine is a key brain neurotransmitter for wakefulness. Blocking histamine H(1) receptors can cause drowsiness and impair cognitive functions, affecting alertness and reaction time.
Area of Science:
- Neuroscience
- Pharmacology
Background:
- Histamine acts as a central nervous system (CNS) neurotransmitter, regulating wakefulness, alertness, and reaction time through H(1), H(2), and H(3) receptors.
- Blood-brain barrier-penetrating H(1)-antagonists can disrupt histamine's homeostatic functions in the CNS, leading to drowsiness and functional impairment.
Purpose of the Study:
- To examine the role of histamine in CNS functions related to wakefulness and alertness.
- To understand how H(1)-antagonists impact CNS functions and the methods used to assess these effects.
Main Methods:
- Utilized subjective and objective tests to evaluate the effects of antihistamines on CNS functions.
- Investigated the mechanisms by which second-generation antihistamines aim to reduce CNS side effects.
Main Results:
- H(1)-antagonists that cross the blood-brain barrier can impair wakefulness, alertness, and reaction time.
- Drowsiness and functional impairment are potential consequences of blocking histamine's CNS activity.
Conclusions:
- Histamine's role in maintaining CNS wakefulness is critical.
- Understanding antihistamine CNS penetration is key to minimizing side effects like drowsiness and impairment.
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