Collapse after Moxidectin (ProHeart 6) in dogs

1,511 reports to the FDA describe collapse in dogs given Moxidectin. That is 3.0% of all reports for this medicine, compared with 0.9% across reports for all dog medicines, so it is reported unusually often with this medicine.

1,511Reports

73%Marked serious

32%Recovered

14%Died or euthanised

Same dayTypical onset

How soon it started

Same day

1,047 89%

1–2 days

34 2.9%

3–7 days

28 2.4%

1–4 weeks

35 3.0%

Over a month

28 2.4%

How the animals did

Recovered

488 32%

Still unwell when reported

547 36%

Died

185 12%

Euthanised

32 2.1%

Not known

259 17%

Problems reported at the same time

1,181 78%

887 59%

501 33%

355 23%

313 21%

258 17%

217 14%

188 12%

Age of the animals

Under 1 year

134

1–3 years

814

4–7 years

315

8–11 years

163

12+ years

About this medicine

Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs).

Products with this ingredient include ProHeart 6, ProHeart 12. 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 Moxidectin cause collapse in dogs?: 1,511 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).

Collapse with similar medicines

Collapse after Ivermectin + Pyrantel (Heartgard Plus) 432 reports · 0.3% of its reports
Collapse after Milbemycin Oxime + Spinosad (Trifexis) 471 reports · 0.4% of its reports
Collapse after Milbemycin Oxime + Praziquantel (Interceptor Plus) 153 reports · 0.5% of its reports
Collapse after Milbemycin Oxime (Interceptor) 163 reports · 0.5% of its reports
Collapse after Selamectin (Revolution) 115 reports · 0.4% of its reports
Collapse after Ivermectin (Heartgard) 109 reports · 0.9% of its reports
Collapse after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 60 reports · 0.7% of its reports

All reported side effects of Moxidectin in dogs · Medicines most reported with collapse