Abnormal ultrasound finding after Ivermectin + Pyrantel (Heartgard Plus) in dogs

203 reports to the FDA describe abnormal ultrasound finding in dogs given Ivermectin + Pyrantel. That is 0.1% of all reports for this medicine, compared with 0.5% across reports for all dog medicines, so it is reported less often than average with this medicine.

203Reports

74%Marked serious

21%Recovered

25%Died or euthanised

14 daysTypical onset

How soon it started

Same day

20 20%

1–2 days

18 18%

3–7 days

9 8.8%

1–4 weeks

22 22%

Over a month

33 32%

How the animals did

Recovered

32 16%

Recovered with lasting effects

11 5.4%

Still unwell when reported

42 21%

Died

18 8.9%

Euthanised

33 16%

Not known

67 33%

Problems reported at the same time

113 56%

96 47%

94 46%

80 39%

63 31%

Abnormal radiograph finding

60 30%

Death

51 25%

Kidney problems

42 21%

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 abnormal ultrasound finding in dogs?: 203 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 14 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).

Abnormal ultrasound finding with similar medicines

Abnormal ultrasound finding after Milbemycin Oxime + Spinosad (Trifexis) 240 reports · 0.2% of its reports
Abnormal ultrasound finding after Moxidectin (ProHeart 6) 268 reports · 0.5% of its reports
Abnormal ultrasound finding after Milbemycin Oxime + Praziquantel (Interceptor Plus) 67 reports · 0.2% of its reports
Abnormal ultrasound finding after Milbemycin Oxime (Interceptor) 59 reports · 0.2% of its reports
Abnormal ultrasound finding after Selamectin (Revolution) 40 reports · 0.1% of its reports
Abnormal ultrasound finding after Ivermectin (Heartgard) 57 reports · 0.5% of its reports

All reported side effects of Ivermectin + Pyrantel in dogs · Medicines most reported with abnormal ultrasound finding