Lethargy after Phenobarbital in dogs

220 reports to the FDA describe lethargy in dogs given Phenobarbital. That is 14% of all reports for this medicine, compared with 11% across reports for all dog medicines.

220Reports
68%Marked serious
31%Recovered
20%Died or euthanised
8 daysTypical onset
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How soon it started

Same day
35 28%
1–2 days
19 15%
3–7 days
8 6.3%
1–4 weeks
17 13%
Over a month
47 37%

How the animals did

Recovered
51 23%
Recovered with lasting effects
17 7.7%
Still unwell when reported
60 27%
Died
17 7.7%
Euthanised
26 12%
Not known
49 22%

Problems reported at the same time

Age of the animals

Under 1 year
2
1–3 years
19
4–7 years
66
8–11 years
64
12+ years
64

About this medicine

Type: medicine.

Questions owners ask

Can Phenobarbital cause lethargy in dogs?
220 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 8 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).

Lethargy with similar medicines

All reported side effects of Phenobarbital in dogs · Medicines most reported with lethargy