Phenobarbitol side effects in dogs

61 reports sent to the FDA between 2011 and 2026 involve Phenobarbitol in dogs. The most reported problems were seizures, lethargy, wobbliness (ataxia). 67% were marked serious.

61Reports
67%Marked serious
1.6%Only medicine involved
30%Recovered
21%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

28 46%
Lethargy
8 13%
Wobbliness (ataxia)
7 11%
Liver problems
6 9.8%
Weakness
5 8.2%
Restlessness or agitation
4 6.6%
Itching
4 6.6%
Diarrhea
4 6.6%
Loss of appetite
4 6.6%
Unable to stand
4 6.6%
Elevated gamma-glutamyl transferase (ggt)
3 4.9%
Drooling
3 4.9%
Paddling
3 4.9%
Behaviour change
3 4.9%
Vomiting
3 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 work as expected
2 3.3%
Didn't stop fleas
1 1.6%
Didn't prevent heartworm
1 1.6%

How soon problems started

Same day
5 16%
1–2 days
5 16%
3–7 days
5 16%
1–4 weeks
5 16%
Over a month
12 38%

Time from the first dose to the first sign, where both dates were reported (32 reports).

How the animals did

Recovered
17 28%
Recovered with lasting effects
1 1.6%
Still unwell when reported
10 16%
Died
4 6.6%
Euthanised
9 15%
Not known
20 33%

Breeds named most often

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

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