Cat repellent collars will not poison cats, but some inferior collars are toxic to cats and can cause physical problems. If the cat always licks the collar, it may also cause gastrointestinal discomfort. In this case, the problem can be solved by simply removing the collar.

However, deworming collars have limited side effects and can be worn for two to three months. You can take them off as long as you make sure that the surrounding environment and the cat are free of fleas and other parasites. Be sure to buy a professional and formal collar for your cat.