The MEDI-DART Projectile, Extension, or Crossbow syringe, invented by a group of central Alberta ranchers, makes medicating pasture cattle easy and less stressful for livestock. The patented MEDI-DART systems are easy to use and inject larger doses of medication than other medicating systems. MEDI-DART is used to give a single intramuscular or subcutaneous injection to livestock without restraining the animal. MEDI-DART also self-ejects once the injection is completed. At the end of the injection an ejector loop is pushed ahead which removes the needle from the animal for easy retrieval of the syringe.

Three variations are available; the Crossbow MEDI-DART, which further increases accuracy, the Projectile MEDI-DART which incorporates the basic principle of the bow and arrow, and the Extension MEDI-DART, which simply uses the added length of a pole. With the Crossbow Projectile system, the syringe can hold 30cc of medication and has a 30 foot range to medicate the animal. With the Bow and Arrow Projectile system, the syringe on the end of the arrow can hold up to 30cc of medication and the user has a 20 foot range. The Extension MEDI-DART can hold up to 35cc of medication and gives the user a 6 foot reach. The syringe is released from the pole after the animal has been poked. MEDI-DARTS use a simple bicycle pump to create air pressure which injects the medication and upon completion of the injection pushes the ejector loop ahead, forcing the needle out of the animal.