Vomiting after Ivermectin (Heartgard) in dogs

The FDA has received 3,182 reports of vomiting in dogs after Ivermectin. That is 26% of all reports for this medicine, compared with 28% across reports for all dog medicines.

3,182Reports

17%Marked serious

67%Recovered

4.0%Died or euthanised

49 daysTypical onset

How soon it started

Same day

509 24%

1–2 days

135 6.3%

3–7 days

87 4.1%

1–4 weeks

212 10.0%

Over a month

1,185 56%

How the animals did

Recovered

2,037 64%

Recovered with lasting effects

103 3.2%

Still unwell when reported

248 7.8%

Died

77 2.4%

Euthanised

49 1.5%

Not known

668 21%

Problems reported at the same time

545 17%

362 11%

346 11%

202 6.3%

192 6.0%

Eye or vision problems

145 4.6%

Liver problems

138 4.3%

Death

119 3.7%

Age of the animals

Under 1 year

493

1–3 years

1,072

4–7 years

812

8–11 years

483

12+ years

182

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 vomiting in dogs?: 3,182 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 49 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).

Vomiting with similar medicines

Vomiting after Ivermectin + Pyrantel (Heartgard Plus) 20,052 reports · 14% of its reports
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 + 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 in dogs · Medicines most reported with vomiting