By the end of 2008, the government says, the makers of albuterol "rescue" inhalers - used by millions to reopen airways during asthma attacks - will have to stop using the ozone-destroying chlorofluorocarbon propellants that power the devices.
Three decades ago, scientists discovered that the CFCs were damaging the atmospheric ozone layer that shields Earth from harmful ultraviolet radiation, and the United States began to phase in a ban on their use.
The transition to other propellants for asthma inhalers has already begun.
Some manufacturers have dropped out of the market, and others have encountered manufacturing snags.
The rest are struggling to meet increased demand, and doctors and pharmacists say they are beginning to see supplies of inhalers tighten.
"This has the potential to be serious, because all asthmatics need to have a bronchodilator available as a rescue medicine," said Glenn M. Silber, an allergist and immunologist with a practice in Howard County, Md.
There were about 20 million people with asthma in the U.S. in 2003, including 6.2 million children, according to the American Lung Association's latest estimates.
Manufacturers say consumers buy 59 million rescue inhalers a year.
Prices to go higher
To ensure there are no supply problems, the Food and Drug Administration is working with manufacturers, said spokeswoman Susan Cruzan, and "does not see a drug shortage associated with the use of albuterol."
But the prices patients pay are going to go higher. The tightening supply for the CFC inhalers is pushing more patients from generics to brand-name versions of the same drug and to CFC-free devices - both of which are significantly more expensive.
Patients typically pay $15 to $22 for a generic CFC albuterol inhaler, and most use about one a month, doctors say. The non-CFC and brand-name versions can cost $45 to $55, according to Brad Houck, a retail pharmacist in Salem, Va., who specializes in hard-to-find pharmaceutical products.
He and others fear that a "gray market" is developing in which middlemen are stockpiling the inhalers and waiting for prices to rise.
In setting the deadline for eliminating CFCs from albuterol inhalers, the FDA reasoned that by Dec. 31, 2008, the drug industry would have time to reformulate and switch to more environmentally benign propellants called hydrofluoroalkanes.
Other inhalers are also in the regulatory cross hairs.
Asthmatics typically use albuterol only in emergencies. For long-term maintenance, they rely on inhalers containing slow-acting steroids. Those are not affected by the 2008 deadline. But eventually those, too, will have to be CFC-free, as will other inhalers containing drugs marketed for people with asthma or chronic obstructive pulmonary disease.
In January, an advisory panel to the FDA recommended that the agency ban the sale of CFC-powered Primatene Mist and similar over-the-counter inhalers used by many asthmatics.
The FDA has not yet acted, and the maker of Primatene, Wyeth Consumer Healthcare, has asked for a delay until 2009 or 2010, until a CFC-free version is ready for market.
CFCs are manufactured hydrocarbons used for decades in refrigerants, such as Freon, and in foams, solvents, fire extinguishers and aerosol propellants.
The move away from CFCs began in the late 1970s, after scientists discovered that the chemicals were destroying the ozone layer.
Cheap, work well
CFC inhalers have remained on the market because of an "essential use" exemption under the Montreal Protocol for ultra-pure, pharmaceutical-grade CFCs. But the FDA ruled in 2005 that all domestic manufacturers would have to stop the production and sale of CFC albuterol inhalers by the end of 2008.
It wouldn't seem that the amount of CFCs in the quarter-ounce of solution in a typical inhaler could pose a threat. But the EPA says the chemical stability that makes CFCs ideal for drug delivery means it is exhaled intact into the atmosphere.
Eventually all 1,100 metric tons allocated this year to manufacturers will be released and make their way to the stratosphere.
There, ultraviolet radiation will break down each CFC molecule, freeing persistent and highly reactive chlorine atoms.
The ban on CFCs in inhalers has been a difficult pill for manufacturers to swallow. Drug makers prefer them, because they don't change the chemistry of the medicine they're delivering and they are not metabolized in the body.
Patients like the CFC albuterol inhalers, too, because they're cheap and work well.
Fortunately, while inventories of the low-cost inhalers have been shrinking, there is no shortage of albuterol itself. There are other delivery systems available - including dry-powder inhalers or liquids sprayed from nebulizer machines. And, there are other drugs that should work as well as albuterol, doctors say.
But they add that these products are not always as portable or as effective as a CFC inhaler. And some patients are reluctant to switch from a product they know will work in an emergency. |
