Lotilaner (Credelio) side effects in cats

901 reports sent to the FDA between 2019 and 2026 involve Lotilaner in cats. The most reported problems were itching, vomiting, breathing problems. 20% were marked serious, and where it was recorded, signs eased after stopping the medicine in 0% of cases.

901Reports
20%Marked serious
67%Only medicine involved
27%Recovered
3.9%Died or euthanised
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About this medicine

Lotilaner kills fleas and ticks; monthly chewable.

Products with this ingredient include Credelio. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

In 2018 the FDA alerted owners and vets that isoxazoline products have been associated with neurologic reactions such as muscle tremors, wobbliness (ataxia) and seizures, including in animals with no history of them.

Most reported side effects

Share = percentage of this medicine's reports that mention the problem. One report can list several problems.

Reports that it didn't work

Some reports are about the medicine not working (for example a cat still getting fleas or heartworm), not about a side effect.

Didn't work as expected
17 1.9%
Didn't stop worms
13 1.4%
Didn't stop mites
8 0.9%
Didn't stop ticks
4 0.4%

How soon problems started

Same day
386 45%
1–2 days
148 17%
3–7 days
56 6.5%
1–4 weeks
130 15%
Over a month
142 16%

Time from the first dose to the first sign, where both dates were reported (862 reports).

How the animals did

Recovered
246 27%
Recovered with lasting effects
1 0.1%
Still unwell when reported
286 32%
Died
27 3.0%
Euthanised
8 0.9%
Not known
333 37%

Breeds named most often

Popular breeds appear more often because there are more of them.

Other isoxazoline flea and tick medicines for cats