Wobbliness (ataxia) after Ivermectin + Pyrantel (Heartgard Plus) in dogs

1,346 reports to the FDA describe wobbliness (ataxia) in dogs given Ivermectin + Pyrantel. That is 0.9% of all reports for this medicine, compared with 2.6% across reports for all dog medicines, so it is reported less often than average with this medicine.

1,346Reports

43%Marked serious

28%Recovered

7.0%Died or euthanised

2 daysTypical onset

How soon it started

Same day

230 33%

1–2 days

140 20%

3–7 days

56 8.1%

1–4 weeks

98 14%

Over a month

170 24%

How the animals did

Recovered

361 27%

Recovered with lasting effects

20 1.5%

Still unwell when reported

151 11%

Died

51 3.8%

Euthanised

43 3.2%

Not known

720 53%

Problems reported at the same time

459 34%

352 26%

274 20%

214 16%

212 16%

151 11%

133 9.9%

122 9.1%

Age of the animals

Under 1 year

305

1–3 years

284

4–7 years

313

8–11 years

227

12+ years

179

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 wobbliness (ataxia) in dogs?: 1,346 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 2 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).

Wobbliness (ataxia) with similar medicines

Wobbliness (ataxia) after Milbemycin Oxime + Spinosad (Trifexis) 2,821 reports · 2.2% of its reports
Wobbliness (ataxia) after Moxidectin (ProHeart 6) 1,147 reports · 2.3% of its reports
Wobbliness (ataxia) after Milbemycin Oxime + Praziquantel (Interceptor Plus) 533 reports · 1.7% of its reports
Wobbliness (ataxia) after Milbemycin Oxime (Interceptor) 712 reports · 2.4% of its reports
Wobbliness (ataxia) after Selamectin (Revolution) 622 reports · 2.1% of its reports
Wobbliness (ataxia) after Ivermectin (Heartgard) 1,237 reports · 10% of its reports
Wobbliness (ataxia) after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 119 reports · 1.4% of its reports
Wobbliness (ataxia) after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 24 reports · 2.1% of its reports
Wobbliness (ataxia) after Ivermectin + Praziquantel 81 reports · 40% of its reports
Wobbliness (ataxia) after Eprinomectin 30 reports · 29% of its reports

All reported side effects of Ivermectin + Pyrantel in dogs · Medicines most reported with wobbliness (ataxia)