Types of drugs, their actions and patterns Flashcards
What factors effect drug dependance?
- Person (age, gender, health)
- Drug (how it’s taken, amount, frequency, duration)
- Environment (social factors)
Why is intravenous drug use considered more harmful than other routes of administration? (needle into vein)
- Rapid onset effect
- Infections from needles at site/through blood or through sharing
What are Pharmacokinetics?
- what the body does to the drug
How do Pharmacodynamics work?
- what the drug does to the body’
Describe the pharmacokinetic process
- Absorption: via skin, oral (small intestine -> liver -> circulation), smoked (mouth/lung lining -> circulation), IV (direct to circulation)
- Distribution: organs with high blood flow first (brain), fat, muscles and skin later
What is the most effective drug?
Smoking as it goes straight to the lungs
Describe the pharmacodynamics process
- Dependance
- Drug tolerance (less affect)
- Withdrawal
- Cross-dependence (one drug takes place of another to continue dependance)
- Agonist effect: decrease or inhibition of the action of a neurotransmitter
- Dopamine - Neurotransmitter related to reward/pleasure
What is the pharmacokinetic half life?
- Time for drug in blood to reduce by 50%
- Short half life/short action more likely to use again sooner
What is pharmacokinetic metabolism?
- mostly via urine, some through lungs
Is it possible to sober someone up?
No
What is pharmacodynamics synapses?
- Brain - millions of pathways (nerves) similar to a mass of electrical wires
- Communication using chemical messages (neurotransmitters)
- Everything that we think, feel and do are the result of these chemical communications
What do drugs act as?
- Act by mimicking normal neurotransmitters by occupying receptor sites and sending “false” messages
What are the effects of depressants?
- Slows body down
- e.g. Alcohol, heroin
What are the effects of hallucinogens?
- Affect perception
- e.g. LSD, magic mushroom
What are the effects of stimulants?
- Speed body up
- e.g. Nicotine, caffeine, cocaine
What is the leading preventable cause of death and disability in Australia?
Tobacco
- more than illicit and alcohol combined
What happens with small doses of stimulants?
increase awareness and concentration, decrease fatigue and amplify positive moods
What happens with larger doses of stimulants?
can cause excessive activity, irritability, nervousness, insomnia, delusions and hallucinations (drug-induced psychosis), convulsions, death
What are the properties of nicotine as a stimulant?
- Dopamine agonist = reinforcing
- Glutamate agonist = stimulant
- Short term effect, small half-life
- Highly addictive
- Improves short term memory
What are the properties of meth as a stimulant?
- Significantly alters levels of dopamine (extreme agonist) and norepinephrine
- reduced appetite
- irregular heartbeat
- high blood pressure
- psychosis
What happens with small doses of depressants?
Relaxation, drowsiness and loss of inhibitions
What happens with larger doses of depressants?
Can cause loss of consciousness, respiratory inhibition, and even death
What are the properties of alcohol & benzo as a depressants?
- GABA agonist = reduces overall brain activity
- Glutamate antagonist = excitatory function reduced (effect of BZD on this system is not clear)
- benzo has a sedative effect
What are the immediate effects of alcohol as a depressants?
- happy, more relaxed, less concentration, slow reflexes, less inhibited
- disinhibited, more confidence, less coordination, slurred speech, intense moods
- confusion, blurred vision, poor muscle control
- nausea, vomiting, sleep
- coma or death