Take the hassle out of flea infestations! Get rid of fleas fast with CapGuard‚Ñ¢ (nitenpyram). Compare to Capstar¬Æ (nitenpyram), same active ingredient used in the vet channel.* CapGuard is an oral flea control medication available over-the-counter to consumers like you. This easy-to-dose tablet begins working within 30 minutes. It cuts out the mess and does exactly what you need it to do: kills fleas fast!