Preparation for Child Psych PRITE and Boards
Jump to: navigation, search
(Created page with "==Introduction== All medications designated as '''antihistamines''' are strong antagonists or inverse agonist at the peripheral and central histamine receptors. * Blockade or th...")
(No difference)

Revision as of 15:00, 25 April 2015

Introduction

All medications designated as antihistamines are strong antagonists or inverse agonist at the peripheral and central histamine receptors.

  • Blockade or the inverse agonism of the peripheral H-1 receptor alleviates allergy symtpoms.
  • Blockade or inverse agonism of the central H-1 receptor increases sedation.
  • Second-generation antihistamines do not cross the blood-brain barrier, and thus are less sedating.

Diphenhydramine (Benadryl)

  • Benadryl is a first-generation antihistamine; in addition to blocking H-1 receptors, it is a potent anti-cholinergic drug and therefore can be used to mitigate extrapyramidal effects of antipsychotics, and has a role in treatment of Parkinson's disease. As noted above, it crosses the blood-brain barrier, and thus quite sedating
    • Its use is generally avoided in the elderly due to significant sedation (risk of falls) and potential for anti-cholinergic toxicity (dry mouth, tachycardia, urinary retention, and delirium)
  • Benadryl is frequently used in inpatient child psychiatry as a PRN medication for it's sedating properties