This is a difficult task, even with the special training anesthesiologists receive. Amyl nitrite has been used in medicine for over 100 years. Amyl nitrite comes in ampoules that resemble some types of smelling salts. When chest pain occurs, the patient breaks open an ampoule and inhales the vapors. Today, doctors prefer to treat angina with tablets containing nitroglycerin, placed under the tongue.
Some doctors use it in their offices to test certain functions of the heart.
Inhalants are also used in food products and for industrial purposes. Nitrous oxide is used as a sweetening agent in whipped cream. Toluene is a solvent found in many types of glue. Abusable drugs are available only through pharmacies by a doctor's prescription. This prevents most experimentation and misuse.