An improved technique for oral administration of solutions of test substances to experimental rats using Mediflon/Medicut intravenous cannula

Abstract

The oral administration of solution of drugs or test substances to experimental rats is often necessary in various pharmacological, toxicological and other biomedical researches. It is scientifically sound and preferable to administer test substances to experimental animals by the same route(s) by which it is taken or meant to be taken by humans as systemic bioavailability; pharmacokinetics and toxicological parameters obtained for the substance will depend markedly on the route used to administer it. The non-ready availability of the standard oral cannula designed for varieties of animals and widespread dearth of technical skills to properly use available improvised techniques in this part of the world has made this route somewhat unpopular among biomedical scientists. In several instances it is abandoned even though initially opted for. This paper narrates and illustrates the technique of using a size 18G Mediflon/Medicut intravenous cannula as an improvised oral cannula to administer solutions of drugs and test substances to experimental rats. Techniques of handling and manipulating the rat with the goal of having the eosophagus as straight as possible and of the oral introduction of the Mediflon/Medicut cannula attached to a syringe containing the solution of test substance are narrated and then illustrated by pictures. The usual problems and difficulties encountered with the oral administration of solutions of test substances using either the syringe alone or introducing it into the feeds or drinking water of the rats were avoided. And the intended doses were accurately delivered at every instance this improvised oral cannula was used.