Poisons and Poisoning

Question 1

Pupils

Answer 1

Constricted: opiates, clonidine

Dilated: atropine, amitryptiline

Question 2

Skin

Answer 2

Sweating: Increased- amphetamine, decreased- atropine

bullae- CO

Question 3

Odour

Answer 3

Ethanol
Cyanide (almonds)
Garlic (arsenic)

Question 4

Blood and urine

Answer 4

Blood: Paracetamol, ethanol, salicylate, CO

Urine:opioids, tricyclics, salicylate

Question 5

How can you decrease absorption?

Answer 5

Emesis (vomming) through ipecac syrup
gastric lavage
Activated charcoal

Question 6

How can you increase elimination?

Answer 6

Activated charcoal- enteral dialysis
Haemoperfusion- blood goes thorugh column of eg charcoal. Areterial
Haemodialysis: venous, methanol goes away very good.
Diuresis

Question 7

What four drugs must we know for certain overdoses?

paracetamol; morphine; benziodiazepines; methanol

Answer 7

N-acetyl cysteine
naloxone (very short half life)
flumazenil
ethanol

Question 8

What are some antidote procedures?

Answer 8

Chelation- e,g desferrioxamine- iron

Question 9

What can be said about paracetamol hepatotoxicty?

Answer 9

The minor metabolite NAPQI produced form CYP2E1 causes liver damage.

NAPQI is usually inactivated by glutathione but limited in the bod.

N-acetyl cysteine is pre cursor for gluthathione

Worth mentioning that despite ethanol being an inducer of CYP2E1, it will also compete with paracetamol, meaning an overdose while drunk won’t cause the same extent of liver damage