Lethargy after Doxycycline in cats

The FDA has received 81 reports of lethargy in cats after Doxycycline. That is 31% of all reports for this medicine, compared with 14% across reports for all cat medicines, so it is reported unusually often with this medicine.

81Reports

70%Marked serious

23%Recovered

42%Died or euthanised

12 daysTypical onset

How soon it started

Same day

9 13%

1–2 days

13 18%

3–7 days

9 13%

1–4 weeks

30 42%

Over a month

11 15%

How the animals did

Recovered

19 23%

Still unwell when reported

22 27%

Died

11 14%

Euthanised

23 28%

Not known

6 7.4%

Problems reported at the same time

42 52%

34 42%

34 42%

20 25%

17 21%

15 19%

12 15%

10 12%

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 lethargy in cats?: 81 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 12 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

Lethargy after Cefovecin (Convenia) 2,068 reports · 24% of its reports
Lethargy after Amoxicillin + Clavulanate (Clavamox) 422 reports · 18% of its reports
Lethargy after Enrofloxacin (Baytril) 180 reports · 11% of its reports
Lethargy after Amoxicillin 105 reports · 20% of its reports
Lethargy after Metronidazole 93 reports · 24% of its reports

All reported side effects of Doxycycline in cats · Medicines most reported with lethargy