Loose stool after Doxycycline in dogs

The FDA has received 50 reports of loose stool in dogs after Doxycycline. That is 1.2% of all reports for this medicine, compared with 0.9% across reports for all dog medicines.

50Reports

66%Marked serious

16%Recovered

18%Died or euthanised

40 daysTypical onset

How soon it started

Same day

3 7.0%

1–2 days

3 7.0%

3–7 days

7 16%

1–4 weeks

5 12%

Over a month

25 58%

How the animals did

Recovered

7 14%

Recovered with lasting effects

1 2.0%

Still unwell when reported

27 54%

Died

3 6.0%

Euthanised

6 12%

Not known

6 12%

Problems reported at the same time

28 56%

22 44%

19 38%

19 38%

15 30%

13 26%

Didn't work as expected

12 24%

Breathing problems

11 22%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Doxycycline treats bacterial and tick-borne infections.

Questions owners ask

Can Doxycycline cause loose stool in dogs?: 50 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 40 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).

Loose stool with similar medicines

Loose stool after Amoxicillin + Clavulanate (Clavamox) 67 reports · 1.2% of its reports
Loose stool after Cefovecin (Convenia) 57 reports · 1.5% of its reports
Loose stool after Enrofloxacin (Baytril) 43 reports · 1.1% of its reports
Loose stool after Metronidazole 157 reports · 5.1% of its reports
Loose stool after Amoxicillin 23 reports · 1.7% of its reports

All reported side effects of Doxycycline in dogs · Medicines most reported with loose stool