Diarrhea after Selamectin (Revolution) in cats

1,031 reports to the FDA describe diarrhea in cats given Selamectin. That is 4.7% of all reports for this medicine, compared with 5.1% across reports for all cat medicines.

1,031Reports

11%Marked serious

9.8%Recovered

10%Died or euthanised

1 daysTypical onset

How soon it started

Same day

165 38%

1–2 days

143 33%

3–7 days

63 15%

1–4 weeks

35 8.1%

Over a month

25 5.8%

How the animals did

Recovered

100 9.7%

Recovered with lasting effects

1 0.1%

Still unwell when reported

170 16%

Died

97 9.4%

Euthanised

9 0.9%

Not known

654 63%

Problems reported at the same time

491 48%

316 31%

314 30%

104 10%

68 6.6%

65 6.3%

57 5.5%

50 4.8%

Age of the animals

Under 1 year

361

1–3 years

216

4–7 years

141

8–11 years

118

12+ years

123

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 diarrhea in cats?: 1,031 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 1 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).

Diarrhea with similar medicines

Diarrhea after Eprinomectin + Esafoxolaner + Praziquantel (NexGard Combo) 118 reports · 3.6% of its reports
Diarrhea after Ivermectin (Heartgard) 51 reports · 5.3% of its reports
Diarrhea after Eprinomectin + Praziquantel 22 reports · 3.8% of its reports
Diarrhea after Milbemycin Oxime (Interceptor) 21 reports · 5.2% of its reports

All reported side effects of Selamectin in cats · Medicines most reported with diarrhea