C - Toxicology

Question 1

list sources of tox samples

Answer 1

antemortem serum / blood
post mortem blood - femoral vein
vitreous humour
stomach contents
liver
urine
hair

Question 2

list 9 of the most common drugs of abuse in tox

Answer 2

ethanol
heroin
cocaine
amphetamines
methadone
benzos
cannabis
pregbalin
new psychoactive compounds

Question 3

in what cases is ethanol tox found

Answer 3

OD
RTAs
liver cirrhosis

Question 4

how can ethanol cause death if other drugs are taken too

Answer 4

additive effects with other depressants

Question 5

who dies of rapid death from heroin

Answer 5

naive users
high tolerane ppl who have quit

Question 6

what do heroin users die from

Answer 6

resp depression
aspiration pneumonitis

Question 7

what does prognosis with heroin depend on

Answer 7

TOLERANCE

Question 8

describe half-life of heroin products with timings

Answer 8

diacetylmorphine (3 mins) –> 6-MAM (30 mins)—> morphine (6 hours)

Question 9

what is actually measured in heroin blood screen

Answer 9

morphine

Question 10

what is a speedball

Answer 10

depressant + stimulant (usually cocaine)

Question 11

acute dangers of cocaine

Answer 11

cardiac dysrhythmias
acute heart failure
myocardial infarction

Question 12

chronic dangers of cocaine

Answer 12

myocardium damage
ventricular arrhythmias
suddendeath

Question 13

which group is most at risk from cocaine death

Answer 13

body packers - bag splits in their stomach so OD

Question 14

how can the effects of cocaine be prolonged

Answer 14

mix with ethanol to get cocaethylene

Question 15

why is cocaine difficult to measure PM

Answer 15

degrades in blood

Question 16

how is cocaine result PM interpreted

Answer 16

with witness behaviour, cardiopathology and pattern of drug use

Question 17

what causes death in amphetamine OD

Answer 17

direct toxic effect on heart

Question 18

complications of amphetamine use

Answer 18

hyperthermia
rhabdomyolysis –> muscle necrosis –> renal failure

Question 19

how long does it take to die from methadone OD once ingested

Answer 19

4-6 hours

Question 20

what doses can kill a child / adult with methadone

Answer 20

5mL child, 60mL adult

Question 21

what is maintenance dose of methadone

Answer 21

5 to 200mL

Question 22

what does the dose of maintenane methadone depend on

Answer 22

heroin tolerance

Question 23

how common in benzo death

Answer 23

very rare alone

Question 24

is cannabis fatal

Answer 24

no

Question 25

how can you determine if cannabis was the cause of a RTA

Answer 25

investigation of impairment that dose would cause

Question 26

what is the 'lethal combination' with cannabis

Answer 26

cannabis + alcohol + driving

Question 27

what % of coroners cases have pregablabin present

Answer 27

9%

Question 28

when is pregablin used

Answer 28

heroin users to cause euphoria prescribed for epilepsy / neuropathic pain

Question 29

give examples of new psychoactive compounds

Answer 29

stimulants synthetic cannabinoids - spice synthetic opioids - carfentanil, isotonitazene hallucinogenic compounds

Question 30

what is carfentanil normally used for

Answer 30

elephant tranquilliser

Question 31

how does carfentanil potency compare to morphine

Answer 31

10,000x more potent

Question 32

how does isotonitazene potency compare to morphine

Answer 32

500x more potent

Question 33

what is the problem with new psychoactive compounds

Answer 33

+++ potency vs original drugs severe ADRs even in low doses

Question 34

what are the problems with interpretation of tox results

Answer 34

need lots of Hx info to interpret results!! - tolerance site dependence PM redistribution of drugs individual variation in response stability of drugs

Question 35

how can PM redistribution of blood affect drug conc

Answer 35

drugs released from tissues into blood after death relates to volume distribution

Question 36

how can the ratio of parent drug:metabolite be used to determine if chronic use or OD

Answer 36

the closer 1:1, then the more likely to be chronic use

Question 37

why is hair used for analysis

Answer 37

only sample that can detect chronic use

Question 38

for how long can drugs be detected in blood

Answer 38

12 hours

Question 39

for how long can drugs be detected in urine

Answer 39

2-3 days

Question 40

how can hair analysis show chronic use

Answer 40

drugs incorporated into hair from blood during growth hair grows 1cm/month therefore every 1cm that contains a drug = 1 month of use

Question 41

limitation of hair use in analysis

Answer 41

limited by hair length - if 5cm hair only, can only see 5 months of drug use contamination by smoke/powder cosmetic Tx can remove drugs from hair darker hair incorporates more drug can not be used to determine cause of death as it takes 5-10 days for hair to come above scalp

Question 42

to what scenarios can hair analysis be applied

Answer 42

child custody cases Ix spiked drinks defencefs drug naive deaths monitoring drug use in employment / driving