The primary difference between flea collars and spot–ons is that flea collars are for prevention; where as, the purpose of spot-ons is to kill fleas if your cat already has them.
Things to Consider:
Application of a Spot–On – A single topical "dose" of a spot–on usually lasts for a month. You need to be sure to apply the product to the nape of your cat´s neck, where he can´t lick it off.
If the Collar Gets Wet – The effectiveness of flea collars is reduced when they get wet. Consequently, you may need to replace them often. When you´re replacing a flea collar, check around your cat´s neck for any skin irritation before attaching a new flea collar.
Safe for Your Cat – When choosing a flea control product, you need to be sure that the product is safe for your cat. Some products may have ingredients that could be harmful to your cat´s health.
