drug dependence Flashcards
(13 cards)
1
Q
outline some physical withdrawal symptoms ?
A
- anxiety/ insomnia
- cramps/ N& V
- tachycardia
- piloerection
- diarrhoea
- 3/4 weeks
2
Q
the origin of dependence is?
A
- related to the dopaminergic miso-limbic reward pathway in the brain
= rewarding effect-> activated by dependent drugs
3
Q
drug dependence may be drug variable and user variable, describe these.
A
-related to degree of reward
user–> absorption and metabolism of drug
- fast absorber-> faster rush
- controlled by genetics
- slower metabolism-> longer lasting
4
Q
tolerance can be?
A
- innate (genetics)
- acquired - metabolic / behavioural
- pharmacodynamic (opiates and reduced cAMP levels)
5
Q
explain how opiate drugs lead to the rewarding effect
A
- bind to opioid receptors present on inhibitory GABA interneurons present in the ventral segmental area
- opioid receptor agonists
- inhibitory action at GABA neuronal–> disinhibition of Dopaminergic neurone it synapses with
- allows for increased DA release by D neurones as inhibition has been relieved
–> rewarding effect
6
Q
what are the treatments for opiate overdose?
A
- naloxone ( antagonist of OR)–> short half life
- methadone – longer half life
7
Q
How does caffiene exhibit its effects?
A
- is a stimulant drug
- PDE inhibitor
- elevated cAMP levels
- activates neurones of rewarding pathway
- is a adenosine r antagonist blocking inhibitory action of adenosine on DA neurones
8
Q
amphetamine and MDMA work by?
A
- both catecholamine release enhancers
- potentiate the actions of catecholamines ( DA for A and 5-HT for MDMA)
9
Q
chronic abuse of MDMA can lead to?
A
- dehydration (with alcohol)
- lesions in the brain
- large reduction of 5-HT N within the brain –> involved in depression and anxiety
- can cause valvulopathy (fibrosis of valve’s via action on 5-HT2B R)
10
Q
list the s/e of cannabis at low doses
A
- euphoria
- happy
- content
- uncontrolled laughter
tetrahydrocannabinol
- agonist of cannabinoid R in the brain
11
Q
effects of cannabis at higher doses include?
A
- dream-like
- ptosis
- chronic usage –>psychiatric conditions
- far more carcinogenic than smoking
12
Q
sedatives work how?
A
- binding to allosteric site of GABA A r (meso-limbic pathway)
- potentiates the response of GABA
- increased inhibitory action on DA neurones
- treat anxiety and insomnia
- opiate withdrawal too
13
Q
disulfiram inhibits which enzyme?
A
aldehyde dehydrogenase
