Behaviour change after Fluoxetine in dogs

The FDA has received 231 reports of behaviour change in dogs after Fluoxetine. That is 8.9% 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.

231Reports

28%Marked serious

29%Recovered

6.1%Died or euthanised

15 daysTypical onset

How soon it started

Same day

27 21%

1–2 days

18 14%

3–7 days

10 7.7%

1–4 weeks

22 17%

Over a month

53 41%

How the animals did

Recovered

47 20%

Recovered with lasting effects

21 9.1%

Still unwell when reported

35 15%

Died

3 1.3%

Euthanised

11 4.8%

Not known

114 49%

Problems reported at the same time

Loss of appetite

53 23%

Lethargy

50 22%

Didn't work as expected

40 17%

33 14%

28 12%

27 12%

26 11%

26 11%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Fluoxetine treats anxiety and behaviour problems.

Questions owners ask

Can Fluoxetine cause behaviour change in dogs?: 231 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 15 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

Behaviour change after Gabapentin 432 reports · 4.8% of its reports
Behaviour change after Selegiline (Anipryl) 165 reports · 4.0% of its reports
Behaviour change after Trazodone 152 reports · 6.0% of its reports
Behaviour change after Clomipramine (Clomicalm) 170 reports · 11% of its reports

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