16 - Drug Dependence Flashcards
Addiction
Chronic disease characterized by drug seeking and use that is compulsive, or difficult to control, despite harmful consequences
Drug Abuse
users consume the substance in amounts or using methods which are directly or indirectly harmful to themselves or others
Drug Dependence
an adaptive state that develops after repeated drug use and which results in withdrawal symptoms upon cessation of drug use
Drug Tolerance
the diminishing effect of a drug which results after repeated administration at a set dose
Psychological dependence
dependence that involves emotional–motivational withdrawal symptoms (e.g. dysphoria, depression, anhedonia, restlessness)
Physical dependence
dependence that involves significant physical–somatic withdrawal symptoms (e.g. fatigue, nausea, seizures, pain, delirium tremens)
What is the molecular target for Cocaine
DA
NAd
5HT uptake systems
What is the molecular target for amphetamine
Monoaminergic transmission
uptake systems
What is the molecular target for Ethanol
GABAa and NMDA receptors
What is the molecular target for Ket and phencyclidine
NMDA glutamate receptors
Reward circuits in the brain in drug dependence
Dopaminergic projection from the ventral tegmental area nucleus accumbens (Ventral Striatum) is essential in drug-dependence
Stages of addiction
Intoxication
Binging
Withdrawal
Craving
What is the opioid peptide that is upregulated in drug withdrawal
Dynorphin
Effect of dynorphin
Activates kappa opiod receptors
Triggers dysphoria by reducing dopamine release
What processes are associated with the PFC (these are impaired in addicts)
o Self control, motivation, working memory, awareness and insight, learning and memory, emotional regulation
Which gene isoforms are more expressed in chronic drug use
FosB
What is hazardous drinking
> 5 units a day for male
>3 units a day female
Acute alcohol intoxication
Euphoria followed by depressive mood
slurring of speech
ataxia
pupil dilation
What neuronal effects does alcohol have
Depressed excitatory transmission and potentiated inhibitory transmission
Long term effects of alcohol
Shrinkage of grey matter
acute GI haemorrhage
pancreatitis
Hepatitis
Methylene Dioxymethamphetamine
MDMA
Ecstasy
MDMA cellular targets
5HT uptake system Dopamine uptake system 5HT2 receptors H2 receptors a2 adrenergic receptors
What does 5HT release do to MDMA
Mediates the behavioural actions
What are temperature effects of MDMA dependent on
5HT
Acute MDMA toxicity
Body temperature elevation
Rhabdomyolysis
Hyponatraemia
What can block rhabdomyolysis
Dantrolene
THC
T9 tetrahydrocannabinol
CB1 receptors
CNS
Mainly presynaptic - modulate glutamate and GABA
CB2 receptors
Peripheral organs
associated with the immune system
Modes of action of cannabinoids
neuromodulators
mainly inhibitory
Risks of cannabinoids
Schizophrenia
depression
gateway drug
memory problems
Cannabidiol
major non-psychotropic cannabinoid compound present in the plant
Nabilone
synthetic analogue of THC
Sativex
product which combines THC and CBD 1:1) Has medical properties
Cannador
product which combines THC and CBD 2:1)
Long term effects of a cocaine/crack addiction
CVS issues - MI and stroke
Cognitive decline
Psychotic symptoms
Major depression and anxiety
Steps in management of addiction
Detoxification Psychological support Medication Evaluation and treatment of mental health problems Long-term follow up
Nalmefene
Opioid antagonist used for reduction of alcohol consumption
What drugs can be given to alcoholics
Thiamine
SSRIs
Dusulfram
Benzodiazepines
Varenicline
α4β2 selective partial agonist at nicotinic receptors
Can be used for nicotine addiction
but SE
Methadone
can be given to opioid addicts (heroin)
