Restlessness or agitation after Ivermectin (Heartgard) in dogs

213 reports to the FDA describe restlessness or agitation in dogs given Ivermectin. That is 1.8% of all reports for this medicine, compared with 1.6% across reports for all dog medicines.

213Reports

32%Marked serious

33%Recovered

7.5%Died or euthanised

15 daysTypical onset

How soon it started

Same day

23 22%

1–2 days

19 18%

3–7 days

5 4.8%

1–4 weeks

14 13%

Over a month

43 41%

How the animals did

Recovered

61 29%

Recovered with lasting effects

9 4.2%

Still unwell when reported

24 11%

Died

11 5.2%

Euthanised

5 2.3%

Not known

103 48%

Problems reported at the same time

Wobbliness (ataxia)

66 31%

Eye or vision problems

56 26%

53 25%

42 20%

40 19%

37 17%

31 15%

30 14%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Ivermectin prevents heartworm disease (monthly).

Products with this ingredient include Heartgard. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Some herding breeds (for example Collies) carry the MDR1 gene variant and can be more sensitive to this drug class at high doses.

Questions owners ask

Can Ivermectin cause restlessness or agitation in dogs?: 213 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 15 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).

Restlessness or agitation with similar medicines

Restlessness or agitation after Ivermectin + Pyrantel (Heartgard Plus) 1,021 reports · 0.7% of its reports
Restlessness or agitation after Milbemycin Oxime + Spinosad (Trifexis) 1,101 reports · 0.8% of its reports
Restlessness or agitation after Moxidectin (ProHeart 6) 508 reports · 1.0% of its reports
Restlessness or agitation after Milbemycin Oxime + Praziquantel (Interceptor Plus) 222 reports · 0.7% of its reports
Restlessness or agitation after Milbemycin Oxime (Interceptor) 250 reports · 0.8% of its reports
Restlessness or agitation after Selamectin (Revolution) 561 reports · 1.9% of its reports
Restlessness or agitation after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 82 reports · 1.0% of its reports
Restlessness or agitation after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 20 reports · 1.7% of its reports

All reported side effects of Ivermectin in dogs · Medicines most reported with restlessness or agitation