Neoplasia after Milbemycin Oxime + Praziquantel (Interceptor Plus) in dogs

70 reports to the FDA describe neoplasia in dogs given Milbemycin Oxime + Praziquantel. That is 0.2% of all reports for this medicine, compared with 0.2% across reports for all dog medicines.

70Reports

99%Marked serious

5.7%Recovered

59%Died or euthanised

152 daysTypical onset

How soon it started

Same day

3 9.7%

1–2 days

2 6.5%

3–7 days

0 0.0%

1–4 weeks

3 9.7%

Over a month

23 74%

How the animals did

Recovered

1 1.4%

Recovered with lasting effects

3 4.3%

Still unwell when reported

17 24%

Died

19 27%

Euthanised

22 31%

Not known

8 11%

Problems reported at the same time

41 59%

7 10%

7 10%

6 8.6%

5 7.1%

Didn't prevent heartworm

5 7.1%

Leucocytosis

5 7.1%

Oral cavity disorder

4 5.7%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Milbemycin Oxime prevents heartworm and controls some intestinal worms (monthly). Praziquantel treats tapeworms.

Products with this combination include Interceptor 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 Milbemycin Oxime + Praziquantel cause neoplasia in dogs?: 70 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 152 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).

Neoplasia with similar medicines

Neoplasia after Ivermectin + Pyrantel (Heartgard Plus) 191 reports · 0.1% of its reports
Neoplasia after Milbemycin Oxime + Spinosad (Trifexis) 265 reports · 0.2% of its reports
Neoplasia after Moxidectin (ProHeart 6) 78 reports · 0.2% of its reports
Neoplasia after Milbemycin Oxime (Interceptor) 48 reports · 0.2% of its reports
Neoplasia after Selamectin (Revolution) 23 reports · 0.1% of its reports

All reported side effects of Milbemycin Oxime + Praziquantel in dogs · Medicines most reported with neoplasia