Emetics and Anti-emetics Flashcards
What centre and trigger zone do emetic drugs target?
emetic centre and chemoreceptor trigger zone
What are emetics used for?
used after toxin ingestion (immediately after)
what is the primary emetic use in small animals? + one other
Apomorphine
- primary in dogs
IV or conjuctiva
hydromorphone can also induce vomiting
what are 2 other emetics used?
A2 - Cats IM (xylazine, dexmedetomidine) Hydrogen peroxide (dogs, not super effective)
What are the uses of antiemetics?
motion sickness, paravirus, gastroenteritic, chemo, uremia, hairballs
What hormones/receptors do antiemetic drugs work on?
dopamine (D2) 5HT receptor(serotonin)
What are two commonly used anti-emetic (phenothiazine drugs - sedatives)?
Metoclopramide (injectable)
Acepromazine
What is the MOA, use and SE of Acepromazine?
MOA: antagonizes dopamine, inhibits the CTZ or emetic centre
Use: decrease vomiting from other cause, antihistamine for dogs, anticholinergic for cats (weak)
SE: hypotension due to alpha adrenergic blockage extrapyramidal signs (diphenhydramine), penile prolapse, prolapse third eye, CYP drug interactions
What is the MOA, use and SE of Metoclopramide?
MOA: inhibits dopamine in the CNS, increases gastric and upper duodenal emptying
Use: small animal, variable PK
SE: extrapyramidal signs
What are two antiemetic (Serotonin antagonists)?
Ondansetron (Zofran)
Maropitant (Cerenia)
What is the MOA and use of Ondansetron?
inhibits serotonin recepters on vagal nerve and centrally (CTZ)
Use: used during chemo, cytotoxic drug and radiation releases serotonin from enterochromaffin cells
- less useful for motion sickness
What is MOA, use and SE of Maropitant (Cerenia)?
MOA: (NK1 antagonist) blocks binding of substance P in emetic centre
Use: to reduce vomiting when induced
- acute vomiting and motion sickness (dogs)
- very good for cats
parvo puppies
SE: bone marrow hypoplasia in young puppies (dont use for parvo puppies<16w)
