27. Practical Prescribing Flashcards
How do we classify poisons?
Intended - alcohol, drugs and deliberate self harm
Unintended - iatrogenic causes in elderly and paracetamol in young
What unit should be used when prescribing liquids?
Mgs
Not mls because there are different strengths
Why do we give dual therapy post MI?
Aspirin does not work for all people due to different pharmacogenetics therefore give 2 anti platelet drugs
What might we see in terms of ventilation and pupils in opiate overdose?
- constricted pupils (miosis)
- hypoventilation
what general investigations would you conduct in suspected poisoning ?
- bloods
- urine
- ECG
What specific management could you do (though would usually do supportive) for poisoning?
- gastric lavage
- activated charcoal
- whole bowel irrigation
- urine alkalinistion - salicylate overdose
- dialysis - methanol overdose
What is the antidote for opiate overdose?
Naloxone
It has a short half life so give it as an infusion
What is the antidote for benzodiazepine overdose?
Flumazenil
What antidote can you give for beta blocker overdose, bradycardia or overdose on cholinergics?
Atropine
What is the antidote for paracetamol overdose?
N-acetylcysteine
What is the antidote for b-blocker or calcium channel blocker overdose?
Glucagon
What is the antidote for digoxin toxicity?
Digibind
Explain paracetamol metabolism and the toxic product that can build up
- undergoes P450 oxidation and can form NAPQI (unconjugated)
- NAPQI is normally conjugated with glutathione
- in substantial overdose, the glutathione is depleted and therefore the conjugation of NAPQI is saturated and it can build up to toxic levels
- therefore treatment is to replace glutathione which is why we give n-acetylcysteine
What are reverse ticks on an ECG indicative of>
Digoxin toxicity
How might a cocaine overdose present?
Acute MI
