Behaviour change after Ondansetron in dogs

49 reports to the FDA describe behaviour change in dogs given Ondansetron. That is 7.4% of all reports for this medicine, compared with 2.5% across reports for all dog medicines, so it is reported unusually often with this medicine.

49Reports
84%Marked serious
16%Recovered
27%Died or euthanised
6 daysTypical onset
SponsoredWorried about your pet? Ask a veterinarian online, 24/7

How soon it started

Same day
9 24%
1–2 days
8 21%
3–7 days
6 16%
1–4 weeks
5 13%
Over a month
10 26%

How the animals did

Recovered
8 16%
Still unwell when reported
21 43%
Died
6 12%
Euthanised
7 14%
Not known
7 14%

Problems reported at the same time

Age of the animals

Under 1 year
5
1–3 years
13
4–7 years
11
8–11 years
7
12+ years
13

About this medicine

Type: medicine.

Questions owners ask

Can Ondansetron cause behaviour change in dogs?
49 reports link the two, but a report alone does not prove the medicine was the cause: other illnesses, other medicines or coincidence can be involved. Your vet can judge it for your animal.
How soon after a dose was it reported?
In half of the reports with dates, it started within 6 days of the first dose.
What should I do?
Don't give another dose until you've spoken to your vet, and keep the packaging so you can tell them the product and dose. Your vet can also report it to the FDA (or you can, through the manufacturer or FDA form 1932a).

Behaviour change with similar medicines

All reported side effects of Ondansetron in dogs · Medicines most reported with behaviour change