A method for inhibiting the plugging of a conduit containing a flowable mixture comprising at least an amount of hydrocarbons capable of forming hydrates in the presence of water and an amount of water, which method comprises adding to the mixture an amount of a functionalized dendrimer effective to inhibit formation and/or accumulation of hydrates in the mixture at conduit temperatures and pressures; and flowing the mixture containing the functionalized dendrimer and any hydrates through the conduit wherein the functionalized dendrimer comprises two or more functional end groups selected from the group consisting of non-cyclic tertiary amine functional end groups, quaternary ammonium functional end groups, polyalkylene glycol functional end groups, quaternary ammonium zwitterionic end groups and phosphate or sulfate end groups.