interactions with drugs Flashcards
what is the structure of the synapse?
axon terminal
synaptic cleft
dendrites
why are action potentials vital for functioning within the body?
○ Drugs can either inhibit or excite them to activate/deactivate the organs
○ “fight or flight” situations
§ Adrenaline
§ noradrenaline
what are drugs of abuse?
- Central nervous system depressants. (alcohol)- Dual role/ Is a CNS stimulant
- Central nervous system stimulants. (caffeine)
- Opiates and Opioids (Narcotics)
- hallucinogens
- marijuana
what are the categories of psychotheraputic drugs?
- The Anatomical Therapeutic Chemical (ATC) Classification System
○ Most simplistic- International Pharmacopeia (WHO)
- European Pharmacopeia
- United States Pharmacopeia (USP)
- Categorised on their mechanism of action
○ Pharmacometrics - Physiological categories
○ Pharmacodynamic
Chemical structure
what are the 5 levels of drug classification in the ATC (anatomincal theraputic chemical?
- organ system or pharamacological classification (alimentary tract and metabolism- class A)
- therputic subgroup (used in diabetes- class A10)
- Pharmacological subgroup (bloog glucose lowering drugs, excluding insulin- class A10B)
- chemical subgroups (biguanides- A10BA)
- chemical substance (metformin- A10B02)
what are the key concepts of psychopharmacology?
dose
tolerance
sensitivity
withdrawal
what is a dosage?
○ How much of the drug do we need to give to get certain responses
○ Individual differences
* Drug strength
what is tolerance?
- How does it change to adapt to the Repeated exposure of the drug
what is sensitivity?
As exposure goes up, sensitivity goes down
Sensitivity levels can change and get worse
* An increased response to a drug with repeated administration.
○ Opposite of tolerance
* Amplified effects, including therapeutic benefits and side effects.
* Mechanisms behind sensitization are not fully understood but thought to involve neuroadaptive changes.
○ Thought to be largely due to neuroadaptive changes
* Understanding tolerance and sensitization is crucial for optimizing drug therapy as they impact dosing, effectiveness, and potential side effects.
○ Dosage and what responses we want to get out of the dose.
what is withdrawal?
Overtime with dependence and increase in tolerance, how does the body react when establishing the homeostatic balance
Reacts with reverse effect of the drug.
* With increased tolerance and dependence on a drug the reduction of that drug typically causes an opposite effect to the drug itself.
○ Can last for days
* Internal systems perpetuate homeostasis by using counter- regulatory methods to create a new state of balance based on the presence of the drug in the system.
* Adaptions include levels of neurotransmitters, hormones, and other substances to adjust for the addition of the drug to the body.
Withdrawal= body is no longer naturally producing the drug
what is the definition of tolerance, accoriding to the NHS, 2014?
diminished response to drugs over the course of repeated or prolonged exposure.
what is rapid tolerance?
4-24 hours after taking the drug
similar to chronic tolerance in effect
what is chronic tolerance?
repeated exposure to a drug
24 hours+ of intermittent exposure
similar to rapid tolerance in effect
what is acute/ tachyphylaxis tolerance?
instant short-term effect of drug on NT and synaptic junction
the initial surge of the drug into the systme
short-term effect
15-30 minutes
what is pharmacodynamic (dispositional) tolerance?
reduction in cellular response to drug. E.g., Desensitisation of receptor, reduction in receptors.
○ Bodies response to the drug
what is pharmokinetic (metabolic) tolerance?
absorption, distribution, metabolism, and excretion of drugs (ADME). Reduced amount of drug reaching site of action.
○ Metabolism to the drug
○ Can change according to how much of the drug we have had
○ Changes over time depending on how much of the drug our body has had
Sensitisation to the drug increases
what is behavioural (conditioned) tolerance?
tolerance to a behavioural effect of drug. Occurs through drug-independent learning or as a form of pharmacodynamic tolerance in the brain
○ Conditional tolerance= behavioural effects
○ Learnt affect
○ Dopamine reward system effect
§ In the brain
Causes more to be taken to keep getting the same effect
explain the dose and response curve:
there will be a right shift on the graph as response lowers over time the more exposure we have to the drug
there will be a left shift in sensitisation
A release of what ion leads to exocytosis of neurotransmitter from the terminal buttons?
calcium
what does an antagonist do?
prevents the storage of the NT’s
on what recpetors fo psilocin work?
seretonin
what type of tolerance is represented by a decrease in sensitivity of the receptor?
pharmacodynamic
what are the 5 stages of neurotrtansmitter relase?
- neurotransmitter is synthesised in cell body or terminal
- neurotransmitter is packaged into vesicles
- nuerotransmitter is released when vesicles fuse
- neurotransmitter binds to and activates postsynaptic receptors
- neurotransmitter is metabolised or transported back into terminal
Is benzodiazepine an agonist or antagonist?
- Agonist
Activates GABA receptor
Is morphine an agonist or antagonist?
- Agonist
Activates opioids receptor
Is alcohol and antagonist, agonist or both?
- Both
○ Activates GABA receptor but also blocks glutamate receptor
Are SSRI antidepressants agonists or antagonists?
- Indirect agonist
block serotonin transporter
Is LSD an antagonist or agonist?
- Agonist
Activates serotonin 5HT receptor
Is caffeine an antagonist or antagonist?
- Antagonist
Blocks adenosine receptor
Is THC an antagonist or agonist?
- Agonist
Activates CB1 receptor
Is MDMA an antagonist or agonist?
Indirect agonist
stimulates the release and inhibits the reuptake of serotonin [5-HT]
What is used to block opioid receptors and prevent overdose?
- naloxone
According to the Centre for Disease Control and Prevention, how many times stronger is fentanyl than heroin?
50x
