Ozone is classified as a toxic gas if inhaled in large quantities. However, it is not toxic when injected slowly into the body by intra-arterial injections, I.V., intramuscularly, subcutaneously or by vaginal or rectal insufflation. Ozone has no side effects when administered, using these methods, in the proper quantities and concentrations. It does not effect healthy cells of any type adversely under those conditions. It is obvious why it is lethal to cancer cells.
Individuals receiving ozone for the first time are usually apprehensive.
They have images of dying from an air embolus. Almost everyone seems to recollect a murder mystery in which the villain killed his victim that way in the hopes of committing the perfect crime. Nitrogen would have to be present in order to cause a toxic reaction and therapeutically only pure medical grade oxygen is used. It would take at least 50 cc of gas given within 2 to 3 seconds. That cannot even be accomplished with a very large bore 18 gauge needle.