Thyroxine side effects in dogs

305 reports sent to the FDA between 2012 and 2026 involve Thyroxine in dogs. The most reported problems were vomiting, loss of appetite, lethargy. 51% were marked serious.

305Reports
51%Marked serious
0.0%Only medicine involved
22%Recovered
13%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

70 23%
58 19%
37 12%
23 7.5%
22 7.2%
20 6.6%
Excessive urination
19 6.2%
Breathing problems
17 5.6%
Behaviour change
16 5.2%
Abnormal ultrasound finding
15 4.9%

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
6 2.0%
Didn't stop worms
5 1.6%
Didn't stop fleas
2 0.7%

How soon problems started

Same day
26 14%
1–2 days
16 8.5%
3–7 days
15 8.0%
1–4 weeks
40 21%
Over a month
91 48%

Time from the first dose to the first sign, where both dates were reported (188 reports).

How the animals did

Recovered
66 22%
Recovered with lasting effects
1 0.3%
Still unwell when reported
124 41%
Died
16 5.2%
Euthanised
23 7.5%
Not known
75 25%

Breeds named most often

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

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