Zonisamide side effects in dogs

308 reports sent to the FDA between 2010 and 2026 involve Zonisamide in dogs. The most reported problems were seizures, lethargy, loss of appetite. 60% were marked serious, and where it was recorded, signs eased after stopping the medicine in 50% of cases.

308Reports
60%Marked serious
5.2%Only medicine involved
30%Recovered
15%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

141 46%
56 18%
53 17%
32 10%
22 7.1%
21 6.8%
Breathing problems
18 5.8%
Behaviour change
18 5.8%
Disorientation
15 4.9%
Blood problems
14 4.5%
Falling
13 4.2%
Fever
10 3.2%

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 stop fleas
3 1.0%
Didn't prevent heartworm
3 1.0%
Didn't stop worms
2 0.6%
Didn't stop ticks
1 0.3%

How soon problems started

Same day
39 21%
1–2 days
34 18%
3–7 days
18 9.6%
1–4 weeks
23 12%
Over a month
73 39%

Time from the first dose to the first sign, where both dates were reported (187 reports).

How the animals did

Recovered
88 29%
Recovered with lasting effects
3 1.0%
Still unwell when reported
94 31%
Died
15 4.9%
Euthanised
31 10%
Not known
77 25%

Breeds named most often

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

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