Lecture 9 Symposium 2 Addictions Psychiatry Flashcards
Define Tolerance
Reduced responsiveness to a drug caused by previous administration
Describe the dispositional mechanism of tolerance
Less drug reaches the active site
What can cause less drug to reach the active site
Decreased absorption
Increased excretion
Increased rate of metabolism to inactive metabolites
Decreased rate of metabolism to active metabolites
Describe the pharmacodynamic mechanism of tolerance
Site of action is less affected by the drug
What causes the site of action to be less affected by the drug
Dow regulation of drug receptor
Reduced signalling down stream of receptor
What is the acute effect of opioids
Constipation
What is the withdrawal effect of opioids
Diarrhoea
What is the acute affect of barbiturates
Anticonvulsant
What is the withdrawal effect of barbiturates
Convulsions
What is the acute effects of cocaine
Elevated mood
What is the withdrawal effect of cocaine
Depressed mood
When VTA neurones are stimulated what do they release
Dopamine
Where do the VTA neurones project
Nucleus accumbens
Prefrontal cortex
What type of drug is cocaine
Monoamine reuptake inhibitor
Incraeses dopamine, serotonin, noradrenaline