Ondansetron side effects in dogs

665 reports sent to the FDA between 2008 and 2026 involve Ondansetron in dogs. The most reported problems were loss of appetite, vomiting, lethargy. 74% were marked serious, and where it was recorded, signs eased after stopping the medicine in 100% of cases.

665Reports
74%Marked serious
0.2%Only medicine involved
16%Recovered
33%Died or euthanised
SponsoredWorried about your pet? Ask a veterinarian online, 24/7

About this medicine

Type: medicine.

Most reported side effects

Share = percentage of this medicine's reports that mention the problem. One report can list several problems.

Reports that it didn't work

Some reports are about the medicine not working (for example a dog still getting fleas or heartworm), not about a side effect.

Didn't prevent heartworm
8 1.2%
Didn't stop fleas
3 0.5%
Didn't stop ticks
3 0.5%
Didn't stop worms
3 0.5%

How soon problems started

Same day
141 25%
1–2 days
100 18%
3–7 days
66 12%
1–4 weeks
90 16%
Over a month
157 28%

Time from the first dose to the first sign, where both dates were reported (554 reports).

How the animals did

Recovered
106 16%
Recovered with lasting effects
1 0.2%
Still unwell when reported
242 36%
Died
72 11%
Euthanised
145 22%
Not known
99 15%

Breeds named most often

Popular breeds appear more often because there are more of them.

Other medicines for dogs