Abdominal pain after Ivermectin + Pyrantel (Heartgard Plus) in dogs

The FDA has received 222 reports of abdominal pain in dogs after Ivermectin + Pyrantel. That is 0.2% of all reports for this medicine, compared with 0.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

222Reports

49%Marked serious

19%Recovered

14%Died or euthanised

3 daysTypical onset

How soon it started

Same day

26 29%

1–2 days

16 18%

3–7 days

13 15%

1–4 weeks

12 13%

Over a month

22 25%

How the animals did

Recovered

41 18%

Recovered with lasting effects

2 0.9%

Still unwell when reported

27 12%

Died

17 7.7%

Euthanised

13 5.9%

Not known

122 55%

Problems reported at the same time

111 50%

92 41%

75 34%

70 32%

42 19%

30 14%

Digestive tract disorder

28 13%

Dehydration

25 11%

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). Pyrantel treats roundworms and hookworms.

Products with this combination include Heartgard Plus, Tri-Heart Plus, Iverhart Plus. 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 + Pyrantel cause abdominal pain in dogs?: 222 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 3 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 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 (Heartgard) 47 reports · 0.4% of its reports
Abdominal pain after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 22 reports · 0.3% of its reports

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