Toxicology:

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lethal dose - dose that will kill 50% of animals

effective dose - cause 50% of the animals to get better/have desired effect of the drug used

Therapeutic index - ration between the lethal and effective dose, if number is big drug is relatively safe, if number is small drug is to be carefully used and can easily overdose and kill/harm

Veterinary poisons information service - vets can get information about poisons in the environment *have to have a subscription to the service

Top enquiries:

NSAIDS = ibruprofen

chocolate

paracetamol

Stimulating gastric evacuation:

triggering areas of the brain that are responsible for vomiting

can be stimulated by smells and taste

key area - chemo receptor trigger zone in medulla

vestibular centre - important for balance, make animal dizzy and brings up contents of stomach

Emetics act on stomach to irritate it

sheep, horse, rabbit and small rodents are unable to vomit

Gastric lavage:

can wash poison out of stomach

2 lines - one which water flows in and water flows out, do not push in, flows by gravity

keep first lavage to send to lab to test what is causing the toxicity

Adsorbents:

activated charcoal - sponge, mops everything up

fullers earth - very good for herbicides

bind to toxin - so doesn't cause further problems

passed through the gut and out in faeces

Cathartics:

help things move through the gut more quickly, once past the stomach - get rid of as quickly as possible

sorbitol - draws water into the gut, helps decrease transit time

Chelating agents: claw - latin word

bind metal ions

bound ions are chemically inert

prevent poisoning

EDTA, binding metal ion in claw like grip

can be given as injection

*chocolate - contains theobromine (dark chocolate the worst)

Ethylene Glycol - anti freeze, not itself toxic but the metabolites, causes troubles in kidneys and nephron tearing. Kidneys start to shut down

Antidote - ethanol, alternative substrate, does not allow lethal toxins to form, switch pathway - IV for quick administration

Organophosphate poisoning:

- OP inhibits cholinesterase resulting in a massive build up of Ach

DUMBELS:

Diahorrea, Urination, Miosis, Bronchoconstriction, Emesis, Lacrimation, Salivation

unlikely to lead to death - but unpleasant problems