Weight loss after Selamectin (Revolution) in dogs

230 reports to the FDA describe weight loss in dogs given Selamectin. That is 0.8% of all reports for this medicine, compared with 1.7% across reports for all dog medicines, so it is reported less often than average with this medicine.

230Reports

21%Marked serious

3.5%Recovered

21%Died or euthanised

5 daysTypical onset

How soon it started

Same day

12 18%

1–2 days

12 18%

3–7 days

10 15%

1–4 weeks

10 15%

Over a month

21 32%

How the animals did

Recovered

8 3.5%

Still unwell when reported

36 16%

Died

38 17%

Euthanised

11 4.8%

Not known

137 60%

Problems reported at the same time

119 52%

94 41%

79 34%

50 22%

48 21%

48 21%

37 16%

Didn't prevent heartworm

27 12%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Selamectin prevents heartworm and treats fleas, ear mites and some worms (spot-on).

Products with this ingredient include Revolution. 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 Selamectin cause weight loss in dogs?: 230 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 5 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).

Weight loss with similar medicines

Weight loss after Ivermectin + Pyrantel (Heartgard Plus) 889 reports · 0.6% of its reports
Weight loss after Milbemycin Oxime + Spinosad (Trifexis) 1,989 reports · 1.5% of its reports
Weight loss after Moxidectin (ProHeart 6) 858 reports · 1.7% of its reports
Weight loss after Milbemycin Oxime + Praziquantel (Interceptor Plus) 515 reports · 1.6% of its reports
Weight loss after Milbemycin Oxime (Interceptor) 348 reports · 1.2% of its reports
Weight loss after Ivermectin (Heartgard) 200 reports · 1.7% of its reports
Weight loss after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 42 reports · 0.5% of its reports
Weight loss after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 29 reports · 2.5% of its reports

All reported side effects of Selamectin in dogs · Medicines most reported with weight loss