Effects of drugs

Question 1

Indicative test

Answer 1

presence of various classes of drugs

Question 2

Evidential test

Answer 2

actual concentrations of drugs using gas chromatography/mass spectrometry or liquid chromatography

Question 3

Cannabis

Answer 3

> 60 cannabinoids

• effects last 2 hours
• half life of THC (tetrahydrocannabinol) = 7 days
• single dose could take 30 days to be eliminated

Question 4

Heroin (diacetylmorphine)

Answer 4

• opiate derived analgesic and narcotic
• once heroin enters body its rapidly metabolised into morphine and binds to opioid receptors
• following injection, heroin crosses the blood-brain barrier within 20 seconds

Question 5

Heroin cont.

Answer 5

• After injection heroin is hydrolysed into 6MAM - 6-acetyl morphine
• ‘Rushing’ occurs within seconds & lasts 1-2mins
• High may last 4-6 hours
• Estimated lethal dose of heroin = 200mg
• Tolerance can increase that to 2g a day
• Rhabdomyolosis may occur (muscle break down leading to organ failure)

Question 6

Cocaine & Crack

Answer 6

• snorted, smoked, ingested and injected
• physiological manifestations:
• severe vasoconstriction, hypertension, cardia arrhythmias, stroke, convulsions
• elimination half life of 1-1.5 hours
• raises body temp by limiting blood flow to skin & can’t sweat
• rhabdomyolosis

Question 7

Lysergic Acid Diethylamide (LSD)

Answer 7

• Potent hallucinogenic
• complex actions on serotonin receptors in central nervous system &also periphery
• plasma half-life of 2.5-4 hours
• Metabolites include hydroxyl LSD, 2-oxo-LSD

Question 8

Psilocybin (Magic mushrooms)

Answer 8

• generally ingested
• many side effects (nausea,, cramping, vomiting, diarrhoea, anxiety, fear, distorted vision)
• High 20 mins-1 hour after ingestion and persists 4-6hours
• previous emotional state may be intensified
• triggers latent psychological states (schizophrenia etc)
• 5-Ht receptor agonist

Question 9

3,4-methylenedioxymethamphetamine (MDMA, Ecstasy)

Answer 9

• class A
• taken orally or crushed into a powder and snorted, injected or smoked
• feelings of intense wellbeing and happiness

Question 10

Methamphetamine (Tik) Meth

Answer 10

• considered to be one of the most addictive substances on the street
• 92% of first time users will re-use
• constricts blood vessels on periphery - leading to ‘meth mouth’
• following death, methamphetamine is redistributed into central blood and the myocardium