The method for automatic dosing of drugs utilizes a microdelivery device which may be implanted in or otherwise administered to an animal or human. A microdelivery device is configured to have a plurality of compartments, each containing at least one drug so that a plurality of doses of the drug(s) are held within the device. In accordance with the present invention, the microdelivery device selectively actuates the compartments to selectively release doses of the drug(s) to provide an efficacious dosing pattern. One primary function of the present invention is to release two or more pesticides in such a pattern that parasites are effectively controlled while preventing the development of tolerance to the drugs within the parasites. Preferably, the microdelivery device is programmable to effectuate the release of the drug(s) at a desired time to maintain efficacious levels of the drug while minimizing the amount of drug which must be used.