Use of agonists and antagonists of nicotinic acetylcholine receptor (A) of insects for non-systemic combating of parasitic insects (fleas, lice and flies) on humans and animals. Independent claims are also included for: an agent and molded articles for non-systemic combating of parasitic insects on humans and animals comprising (A). ACTIVITY : Antiparasitic; Plant Protectant; Insecticide. MECHANISM OF ACTION : Nicotinic acetylcholine receptor agonist; Nicotinic acetylcholine receptor antagonist.