Nausea after Levothyroxine in dogs

24 reports to the FDA describe nausea in dogs given Levothyroxine. That is 0.8% of all reports for this medicine, compared with 0.4% across reports for all dog medicines, so it is reported unusually often with this medicine.

24Reports

38%Marked serious

29%Recovered

13%Died or euthanised

178 daysTypical onset

How soon it started

Same day

2 13%

1–2 days

2 13%

3–7 days

1 6.3%

1–4 weeks

0 0.0%

Over a month

11 69%

How the animals did

Recovered

6 25%

Recovered with lasting effects

1 4.2%

Still unwell when reported

5 21%

Died

1 4.2%

Euthanised

2 8.3%

Not known

9 38%

Problems reported at the same time

12 50%

6 25%

5 21%

5 21%

Didn't work as expected

4 17%

Kidney problems

4 17%

Death

3 13%

Diarrhea

3 13%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Levothyroxine treats an underactive thyroid.

Questions owners ask

Can Levothyroxine cause nausea in dogs?: 24 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 178 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).

Nausea with similar medicines

Nausea after Trilostane (Vetoryl) 63 reports · 0.5% of its reports
Nausea after Insulin 27 reports · 0.4% of its reports
Nausea after Phenylpropanolamine (Proin) 40 reports · 1.0% of its reports

All reported side effects of Levothyroxine in dogs · Medicines most reported with nausea