Tarry or black stool after Gabapentin in dogs

The FDA has received 73 reports of tarry or black stool in dogs after Gabapentin. That is 0.8% of all reports for this medicine, compared with 0.1% across reports for all dog medicines, so it is reported unusually often with this medicine.

73Reports

71%Marked serious

21%Recovered

26%Died or euthanised

6 daysTypical onset

How soon it started

Same day

6 10%

1–2 days

14 24%

3–7 days

13 22%

1–4 weeks

14 24%

Over a month

11 19%

How the animals did

Recovered

15 21%

Still unwell when reported

24 33%

Died

8 11%

Euthanised

11 15%

Not known

15 21%

Problems reported at the same time

49 67%

36 49%

30 41%

24 33%

23 32%

19 26%

19 26%

19 26%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Gabapentin used for pain and to reduce stress or anxiety.

Questions owners ask

Can Gabapentin cause tarry or black stool in dogs?: 73 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 6 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).

All reported side effects of Gabapentin in dogs · Medicines most reported with tarry or black stool