Didn't stop worms after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) in dogs

The FDA has received 335 reports of didn't stop worms in dogs after Lotilaner + Moxidectin + Praziquantel + Pyrantel. That is 11% of all reports for this medicine, compared with 8.4% across reports for all dog medicines.

335Reports

3.3%Marked serious

0.0%Recovered

0.6%Died or euthanised

54 daysTypical onset

How soon it started

Same day

8 2.6%

1–2 days

9 2.9%

3–7 days

9 2.9%

1–4 weeks

86 27%

Over a month

201 64%

How the animals did

Still unwell when reported

19 5.7%

Died

1 0.3%

Euthanised

1 0.3%

Not known

314 94%

Problems reported at the same time

Diarrhea

24 7.2%

Didn't work as expected

23 6.9%

20 6.0%

9 2.7%

6 1.8%

5 1.5%

4 1.2%

4 1.2%

Age of the animals

Under 1 year

145

1–3 years

103

4–7 years

8–11 years

12+ years

About this medicine

Lotilaner kills fleas and ticks; monthly chewable. Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs). Praziquantel treats tapeworms. Pyrantel treats roundworms and hookworms.

Products with this combination include Credelio Quattro. 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.

Questions owners ask

Can Lotilaner + Moxidectin + Praziquantel + Pyrantel cause didn't stop worms in dogs?: 335 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 54 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).

Didn't stop worms with similar medicines

Didn't stop worms after Fluralaner (Bravecto) 629 reports · 0.9% of its reports
Didn't stop worms after Afoxolaner (NexGard) 1,124 reports · 2.0% of its reports
Didn't stop worms after Sarolaner (Simparica) 388 reports · 2.3% of its reports
Didn't stop worms after Lotilaner (Credelio) 552 reports · 5.5% of its reports
Didn't stop worms after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 2,103 reports · 23% of its reports

All reported side effects of Lotilaner + Moxidectin + Praziquantel + Pyrantel in dogs · Medicines most reported with didn't stop worms