Tachycardia after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) in dogs

The FDA has received 32 reports of tachycardia in dogs after Ivermectin + Praziquantel + Pyrantel. That is 0.4% of all reports for this medicine, compared with 0.5% across reports for all dog medicines.

32Reports

53%Marked serious

31%Recovered

22%Died or euthanised

Same dayTypical onset

How soon it started

Same day

15 75%

1–2 days

3 15%

3–7 days

0 0.0%

1–4 weeks

0 0.0%

Over a month

2 10%

How the animals did

Recovered

10 31%

Still unwell when reported

1 3.1%

Died

5 16%

Euthanised

2 6.3%

Not known

14 44%

Problems reported at the same time

17 53%

15 47%

12 38%

7 22%

7 22%

5 16%

4 13%

Recumbency

4 13%

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). Praziquantel treats tapeworms. Pyrantel treats roundworms and hookworms.

Products with this combination include Iverhart Max. 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 + Praziquantel + Pyrantel cause tachycardia in dogs?: 32 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 the same 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).

Tachycardia with similar medicines

Tachycardia after Ivermectin + Pyrantel (Heartgard Plus) 204 reports · 0.1% of its reports
Tachycardia after Milbemycin Oxime + Spinosad (Trifexis) 209 reports · 0.2% of its reports
Tachycardia after Moxidectin (ProHeart 6) 628 reports · 1.2% of its reports
Tachycardia after Milbemycin Oxime + Praziquantel (Interceptor Plus) 55 reports · 0.2% of its reports
Tachycardia after Milbemycin Oxime (Interceptor) 78 reports · 0.3% of its reports
Tachycardia after Selamectin (Revolution) 86 reports · 0.3% of its reports
Tachycardia after Ivermectin (Heartgard) 82 reports · 0.7% of its reports

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