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

505 reports to the FDA describe abnormal radiograph finding in dogs given Ivermectin + Pyrantel. That is 0.3% of all reports for this medicine, compared with 0.9% across reports for all dog medicines, so it is reported less often than average with this medicine.

505Reports

64%Marked serious

18%Recovered

17%Died or euthanised

20 daysTypical onset

How soon it started

Same day

43 17%

1–2 days

34 13%

3–7 days

23 9.1%

1–4 weeks

50 20%

Over a month

103 41%

How the animals did

Recovered

69 14%

Recovered with lasting effects

22 4.4%

Still unwell when reported

96 19%

Died

41 8.1%

Euthanised

45 8.9%

Not known

232 46%

Problems reported at the same time

Vomiting

203 40%

Loss of appetite

159 31%

Lethargy

150 30%

Didn't prevent heartworm

132 26%

108 21%

106 21%

85 17%

83 16%

Age of the animals

Under 1 year

1–3 years

146

4–7 years

119

8–11 years

128

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 radiograph finding in dogs?: 505 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 20 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 radiograph finding with similar medicines

Abnormal radiograph finding after Milbemycin Oxime + Spinosad (Trifexis) 630 reports · 0.5% of its reports
Abnormal radiograph finding after Moxidectin (ProHeart 6) 498 reports · 1.0% of its reports
Abnormal radiograph finding after Milbemycin Oxime + Praziquantel (Interceptor Plus) 164 reports · 0.5% of its reports
Abnormal radiograph finding after Milbemycin Oxime (Interceptor) 138 reports · 0.5% of its reports
Abnormal radiograph finding after Selamectin (Revolution) 149 reports · 0.5% of its reports
Abnormal radiograph finding after Ivermectin (Heartgard) 103 reports · 0.9% of its reports
Abnormal radiograph finding after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 52 reports · 0.6% of its reports

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