in accordance with one preferred embodiment of the invention , a method of animal parasite control is provided which involves a combination of methoprene ( or hydroprene ), pyriproxyfen and an adulticide that is effective against parasites such as fleas , flea eggs , and other potential targets . this combination of active ingredients can produce a topical formulation that provides broad protection against parasites . preferably , the treatment of different parasites can be targeted by including a particular adulticide including , but not limited to , macrocyclic lactones , natural pyrethrins , synthetic pyrethroids , etofenprox , neo - nicotinoids , phenylpyrazoles , or combinations thereof . the adulticide or combination of adulticides should be present in an amount effective to control parasites in the adult state , preferably between 1 % and 90 % of the total administration . the igrs should be present in an amount effective to control parasites in the juvenile state . the amount of pyriproxyfen is preferably between 0 . 005 % and 5 % of the total administration . the amount of methoprene ( or hydroprene ) is preferably between 0 . 01 % and 10 % of the total administration . in a preferred embodiment of the invention , the ratio of methoprene to pyriproxyfen is in the range of 20 : 1 to 1 : 20 by weight . it should be understood that the application of methoprene ( or hydroprene ), pyriproxyfen and an adulticide can be , without limit to any specific ordering of the application . thus , it is possible to apply methoprene ( or hydroprene ), pyriproxyfen , and the adulticide in a single combined formulation or in succession and achieve desirable benefits . in one preferred embodiment of the invention , the insecticide composition of the invention can be packaged in a single dose package . single dose containers make storage , use , and disposal more convenient for animal owners . in another preferred embodiment of the invention , the two igrs and the adulticide can be packaged in a container having two associated , preferably attached , but individual , separated chambers to prevent the mixing of these ingredients prior to the administration to reduce cross - reactivity and improve the shelf - life and efficacy of a formulation where the adulticide needs to be separated from methoprene and pyriproxyfen . prior to administration , the packages containing the first and second formulations in their respective separate chambers are opened , and the first and second formulations are dispensed simultaneously or at least at about the same time to the animal . in another preferred embodiment of the invention , the igrs and the adulticide is applied to the surrounding of the animal , such as a pet bed or a carpet . in another preferred embodiment of the invention , the igrs and the adulticide is prepared in liquid form with a carrier including 1 % to 70 % aerosol propellants . in another preferred embodiment of the invention , the igrs and the adulticide is prepared in liquid form to be dispensed to surfaces via pump spray . it is understood that the active ingredients need not be mixed together prior to administration of the topical formulation to the animal , but may be stored in suitable carriers separately . suitable carriers for the igrs and the adulticide include , but are not limited to , vegetable oils , surfactants , glycols , esters , light petroleum , aldehydes , lactones , triglycerides , amides , silicone polyether copolymers , dialkyl fatty acid amides , pyrrolidones , aqueous dispersions , water , and combinations thereof . the carrier is preferably n , n dialkyl fatty acid amide , and most preferably n , n dimethyl octanamide . the carriers should be present between 1 % to 99 % of the total weight of the composition . because compositions in accordance with preferred embodiments of the invention can be formulated with a relatively high concentration of active ingredients , a relatively small application of a spot or line on the animal can effectively prevent and control parasite infestation on the animal for approximately one , two and even four or more weeks post - administration . in the preparation of a formulation for use on animals , there are several parameters that should be considered . these are : ( a ) concentration high enough to minimize the volume of the topical applied to the animal ( one would not want to put 20 ml , e . g ., onto a small dog ). ( b ) concentration low enough to achieve effective translocation of the topical insecticide over the animal &# 39 ; s skin . ( c ) the formulation should be stable for six months at 40 ° f . and 75 % relative humidity , room temperature and − 10 ° f . this helps ensure that the formulation remains stable under the conditions that it could meet in commerce . ( d ) safe to use on the intended animal — particularly non - irritating to at least the intended animal , since the product is applied to the skin . also safe if ingested by the animal ; ingestion can occur when pets groom themselves . ( e ) safe to use by the consumer . ( f ) efficacious in use — should kill greater than 90 % of the fleas and ticks up to 28 days . ( g ) efficacy would be reduced if crystallization occurred in the package . ( h ) needs to be aesthetically pleasing —“ no oily drop ” on the animal when applied . ( i ) fast drying to reduce the chance of the animal shaking off the liquid thereby reducing efficacy . ( j ) microbiologically stable . the proposed mechanism of synergy is not to be construed as limiting in any way . however , it is believed that methoprene and hydroprene are volatile , with high mobility and therefore capable of migrating throughout an infested area . it is believed that pyriproxyfen possesses long - term chemical stability and potency . thus , a combination of the migratory property of a mobile igr such as methoprene or hydroprene with the efficacy of pyriproxyfen achieves increased parasiticidal activity multiplicatively , rather than offering mere additive results . it can be advantageous to co - administer additional components to increase the efficacy and to reduce the irritation of insecticides to the skin of animals . the formulation can advantageously contain spreading agents such as n - octyl pyrrolidone and dioctylsulfosuccinimide , fragrances , and / or antioxidants . other additives to the insecticidal composition include but are not limited to fragrances , surfactants and spreading agents to increase performance such as polyoxyethylene ( 20 ) sorbitan monolaurate ( commercially available as polysorbate 20 or tween ® 20 ) and polyoxyethylene ( 20 ) sorbitan monooleate ( commercially available as polysorbate 80 or tween ® 80 ), and isopropyl myristate . polymers such as agar , gelatin , alginate , and cationic polymers such as cationic guar , cationic cellulose , cationic acrylates , and polyoxymethylene urea may also be added to provide enrobing of the insecticide to improve safety and adhesion to skin and hair . in practice , an effective amount of the insecticidal compositions as described herein may be applied to a companion animal , preferably a dog or a cat , as a foaming shampoo , dip , aerosol spray , pump spray , powder , lotion , emulsifiable concentrate , aqueous or liquid flowable , slow release collar , suspension concentrate , powder , and by any other methods suitable for administering topical compositions to animals . it will thus be seen that the objects set forth above , among those made apparent from the preceding description , are efficiently attained and , since certain changes may be made in carrying out the above method and in the composition set forth without departing from the spirit and scope of the invention , it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense . the following examples of formulations containing two igrs and one adulticide active ingredients are given for purposes of illustration only and are not intended to be construed in a limiting manner . a formulation i consistent with an embodiment of the invention is prepared by mixing 0 . 1 % pyriproxyfen , 3 . 0 % methoprene or hydroprene , 40 % etofenprox and 56 . 9 % diisopropyl adipate ( dipa ) carrier by weight . a formulation ii consistent with an embodiment of the invention is prepared by mixing 0 . 05 % pyriproxyfen , 10 . 0 % methoprene or hydroprene , 85 % phenothrin and 4 . 95 % dipa carrier by weight . a formulation iii consistent with an embodiment of the invention is prepared by mixing 5 . 0 % pyriproxyfen , 0 . 1 % methoprene or hydroprene , 10 % fipronil and 84 . 9 % dipa carrier by weight . while there have been shown , described and pointed out novel features of the present invention as applied to preferred embodiments thereof , it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit of the invention . it is the intention , therefore , to be limited only as indicated by the scope of the claims appended hereto . it is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which , as a matter of language , might be said to fall therebetween .