Routes of administration

Publisher Summary Substances such as chemical elements, compounds, drugs, antibodies, cells, or other agents may be administered by different routes. This chapter discusses the administration routes, techniques and guidelines for safe injection volumes, and sites of administration. Rats can be trained to accept handling and restraining and can become familiar with their handlers. Though time-consuming, it is essential to minimize distress. All procedures should therefore be carried out only by persons well known to the animal. The simplest method for administering substances is to mix them with food or drinking water. It is possible to administer substances directly into the stomach with accurate dosages and reliable timing. When a liquid volume is administered by gavage a substantial amount of the dose passes rapidly through the stomach to the small intestine. Intragastric administration is carried out using a special blunt-ended, curved, or straight needle with a ball tip. The ball tip helps to prevent the needle from damaging the oesophagus and from passing through the glottal opening into the trachea. Further, parenteral administration involves application of a substance to the body in a manner that passes the gastrointestinal tract. Giving small amounts of solutions is called an injection, while administration of larger quantities of solutions is named an infusion. In both cases the skin must be penetrated by a needle. Other methods of parenteral administration include subcutaneous or intraperitoneal implantation of an osmotic pump and, without penetrating the skin, inhalation or topical application.