From the FDA:

The U.S. Food and Drug Administration says users of epinephrine inhalers containing chlorofluorocarbons (CFCs) should plan now to get a prescription for a replacement product because these inhalers will not be made or sold after Dec. 31, 2011.

Epinephrine inhalers, marketed by Armstrong Pharmaceutical Inc. as Primatene Mist, are the only FDA-approved inhalers for the temporary relief of occasional symptoms of mild asthma that are sold over-the-counter in retail stores without a prescription. The product uses CFCs to propel the medicine out of the inhaler so that consumers can breathe it into their lungs.

However, Primatene Mist will no longer be available by year’s end because no CFC-containing epinephrine inhalers can be made or sold after Dec. 31, 2011, to comply with obligations made under the Montreal Protocol on Substances that Deplete the Ozone Layer. This is an international agreement signed by the United States, in which countries agreed to phase-out substances that deplete the ozone layer, including CFCs, after certain dates.

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