Toxicology And Illicit Drug Confirmation Flashcards
What is toxicology ?
Examination of biological samples for the presence of drugs
What is toxicology divided into ?
Criminal toxicology and road traffic toxicology
What is a receptor ?
A molecule on the cell membrane that responds only to specific hormones, antigens or drugs
What is an agonist ?
An agonist is a drug that binds to and fully activates a receptor
What is an antagonist ?
An antagonist is a drug that binds to and inhibits receptor activity
What is a partial agonist ?
A partial agonist binds to a receptor weakly, it does not elicit a full effect and is blocking the receptor from being activated fully by an agonist thus has antagonist like effects
How does GABA work ?
Causing membrane depolarisation by increasing the flow of negative CI ions across the membrane
What activates GABA receptors ?
GABA or numerous drugs
How does glutamate work ?
Increases the frequency of NA+ and CA+ ions across the membrane
What is dopamine associated with ?
Pleasure and addiction
What is the substance in alcohol that makes it alcohol ?
Ethanol
What are the different types of alcohol of forensic interest ?
-methanol
-iso-propanol
-ethylene glycol
What is the mechanism of alcohol ?
Alcohol binds to alpha sub unit of GABA receptor and increases the likelihood and potency of the GABA ligand
How does memory loss occur ?
Inhibition of GABA
Where is alcohol absorbed from ?
Duodenum
How much alcohol enters the bloodstream from the stomach ?
20%
Why does consumption of food slow down absorption of alcohol ?
Delays gastric emptying
What is the fatal level of alcohol ?
> 400mg
What does CNS depressants and the use of alcohol cause ?
Synergistic effect
Why is heroin never found in toxicology results when tested for ?
Metabolises fast
When can you state that it’s a heroin overdose ?
If 6-MAM is present in results
What is the mechanism of heroin ?
- Morphine binds to opiate receptors
- Morphine inhibits GABA release
- Dopamine release no longer inhibited
What is speedballing ?
Mixing heroin and cocaine and taken by injection
What two ways does Heroin OD typically occur ?
-prolonged absence
-relapse
What is the mechanism for cocaine ?
-dopamine retake blocked by cocaine
-build up of dopamine in synaptic cleft
-effects are intense and short lived
What do toxicology tests for cocaine show ?
Benzoylecgonine
What is the psychoactive and toxic element of cocaine ?
Cocaethylene
What is cocaine OD typically related to ?
-cardiovascular complications
-binge use
What is cocaine OD accompanied by ?
-convulsions
-foaming of the mouth
-loss of consciousness
What is the base form of cocaine ?
Crack
How are crack rocks formed ?
-baking soda
-heated
-cooled quickly
In what form is cocaine more addictive ?
when smoked
What i8s the mechanism for benzodiazepines ?
-bind to gamma sub unit on GABA receptor
What is doctor shopping ?
visiting multiple physicians to obtain multiple prescriptions
What affect does ecstasy (MDMA) ?
Serotonin shock syndrome (heatstroke)
- lowers the bodies ability to regulate body temperature