Vomiting after Ivermectin + Pyrantel (Heartgard Plus) in dogs

The FDA has received 20,052 reports of vomiting in dogs after Ivermectin + Pyrantel. That is 14% of all reports for this medicine, compared with 28% across reports for all dog medicines, so it is reported less often than average with this medicine.

20,052Reports

36%Marked serious

54%Recovered

2.3%Died or euthanised

1 daysTypical onset

How soon it started

Same day

5,951 50%

1–2 days

1,431 12%

3–7 days

383 3.2%

1–4 weeks

892 7.5%

Over a month

3,254 27%

How the animals did

Recovered

10,800 54%

Recovered with lasting effects

91 0.5%

Still unwell when reported

919 4.6%

Died

298 1.5%

Euthanised

161 0.8%

Not known

7,783 39%

Problems reported at the same time

Diarrhea

3,812 19%

Lethargy

2,820 14%

Loss of appetite

2,079 10%

Digestive tract disorder

954 4.8%

Didn't stop worms

858 4.3%

Didn't work as expected

682 3.4%

Liver problems

591 2.9%

Tremors

513 2.6%

Age of the animals

Under 1 year

3,590

1–3 years

5,798

4–7 years

4,768

8–11 years

2,807

12+ years

1,262

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 vomiting in dogs?: 20,052 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 1 day 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).

Vomiting with similar medicines

Vomiting after Milbemycin Oxime + Spinosad (Trifexis) 75,323 reports · 58% of its reports
Vomiting after Moxidectin (ProHeart 6) 12,413 reports · 25% of its reports
Vomiting after Milbemycin Oxime + Praziquantel (Interceptor Plus) 7,113 reports · 23% of its reports
Vomiting after Milbemycin Oxime (Interceptor) 4,379 reports · 15% of its reports
Vomiting after Selamectin (Revolution) 3,074 reports · 10% of its reports
Vomiting after Ivermectin (Heartgard) 3,182 reports · 26% of its reports
Vomiting after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 3,567 reports · 42% of its reports
Vomiting after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 197 reports · 17% of its reports
Vomiting after Ivermectin + Praziquantel 40 reports · 20% of its reports
Vomiting after Eprinomectin 20 reports · 19% of its reports

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