Tachycardia after Doxycycline in dogs

The FDA has received 68 reports of tachycardia in dogs after Doxycycline. That is 1.7% of all reports for this medicine, compared with 0.5% across reports for all dog medicines, so it is reported unusually often with this medicine.

68Reports

88%Marked serious

21%Recovered

44%Died or euthanised

7 daysTypical onset

How soon it started

Same day

12 22%

1–2 days

1 1.8%

3–7 days

16 29%

1–4 weeks

10 18%

Over a month

16 29%

How the animals did

Recovered

14 21%

Still unwell when reported

20 29%

Died

9 13%

Euthanised

21 31%

Not known

4 5.9%

Problems reported at the same time

35 51%

34 50%

33 49%

31 46%

27 40%

26 38%

24 35%

24 35%

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 tachycardia in dogs?: 68 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 7 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).

Tachycardia with similar medicines

Tachycardia after Amoxicillin + Clavulanate (Clavamox) 82 reports · 1.5% of its reports
Tachycardia after Cefovecin (Convenia) 43 reports · 1.1% of its reports
Tachycardia after Enrofloxacin (Baytril) 73 reports · 1.9% of its reports
Tachycardia after Metronidazole 56 reports · 1.8% of its reports

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