Histamine chemistry Flashcards
1
Q
Give three examples of first generation anti-histamines?
A
- Diphenhydramine
- Chlorphenamine
- Promethazine
2
Q
GIve two examples of second generation anti-histamines?
A
- Loratidine
- Cetirizine
3
Q
Give an example of a third generation anti-histamine?
A
- Levocetirizine
- Fexofenadine
4
Q
What are the issues (but potentially beneficial) with first generation anti-histamines (and second)?
A
- Drowsiness (effects can last for 24hrs+)
- Drowsiness less of an issue for second generation histamines
5
Q
What are anti-histamines’ role in the body?
A
- Used by immune system to protect cells from infection
6
Q
Where can anti-histamines be found?
A
- Smooth muscle contraction
- Vasodilation
- Gastric acid secretion
- Nervous system, neurotransmitter, sleep regulation
- Male sexual function
- Bone marrow
7
Q
What is histamine’s biological origin? (how is histamine synthesised in the body?)
A
- From the amino acid L-histidine (found in food)
> Histidine decarboxylase (PLP enzyme) - Histamine
8
Q
What are tautomers?
A
Isomers that readily convert; e.g. keto-enol, lactam-lactim and amine-imine (hydrogens swapping about)
