The endotracheal route for medication is useful in emergency situations. Epinephrine, atropine, and naloxone have proved to be effective when administered by this route. Experience with lidocaine is largely anecdotal, but the available information and the drug's chemical properties indicate that endotracheal lidocaine may be considered if necessary. Drugs that should not be given by the endotracheal route include bretylium, diazepam, calcium salts, isoproterenol, norepinephrine, and sodium bicarbonate.