Abdominal pain after Ivermectin (Heartgard) in dogs

The FDA has received 47 reports of abdominal pain in dogs after Ivermectin. That is 0.4% of all reports for this medicine, compared with 0.4% across reports for all dog medicines.

47Reports

62%Marked serious

15%Recovered

30%Died or euthanised

28 daysTypical onset

How soon it started

Same day

6 21%

1–2 days

2 6.9%

3–7 days

4 14%

1–4 weeks

3 10%

Over a month

14 48%

How the animals did

Recovered

6 13%

Recovered with lasting effects

1 2.1%

Still unwell when reported

11 23%

Died

6 13%

Euthanised

8 17%

Not known

15 32%

Problems reported at the same time

25 53%

25 53%

23 49%

18 38%

14 30%

13 28%

13 28%

11 23%

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 abdominal pain in dogs?: 47 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 28 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).

Abdominal pain with similar medicines

Abdominal pain after Ivermectin + Pyrantel (Heartgard Plus) 222 reports · 0.2% of its reports
Abdominal pain after Milbemycin Oxime + Spinosad (Trifexis) 301 reports · 0.2% of its reports
Abdominal pain after Moxidectin (ProHeart 6) 193 reports · 0.4% of its reports
Abdominal pain after Milbemycin Oxime + Praziquantel (Interceptor Plus) 48 reports · 0.2% of its reports
Abdominal pain after Milbemycin Oxime (Interceptor) 96 reports · 0.3% of its reports
Abdominal pain after Selamectin (Revolution) 55 reports · 0.2% of its reports
Abdominal pain after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 22 reports · 0.3% of its reports

All reported side effects of Ivermectin in dogs · Medicines most reported with abdominal pain