Environmentally-friendly inhalers

Environmentally-friendly inhalers

Suzanne Rutkowski, CMA For the past four decades, metered dose inhalers (MDIs) have been the most popular way to deliver asthma medications. They have...

214KB Sizes 1 Downloads 41 Views

Suzanne Rutkowski, CMA For the past four decades, metered dose inhalers (MDIs) have been the most popular way to deliver asthma medications. They have been the device used to deliver both bronchodilators and anti-inflammatory medications safely and effectively. Currently, many of these MDIs use a propellant that contains chlorofluorocarbons (CFCs). The propellant helps deliver the medication from the canister into the airways of the lungs. Over the years, scientists have discovered that CFCs are contributing to the destruction of the important ozone layer in the earth’s atmosphere. 28

|

ASTHMA MAGAZINE

November/December 2002

Eventually, inhalers containing CFCs will no longer be available because of the harmful effects of CFCs on the earth’s atmosphere. This article will explain when and how this will take place. Before you read further, remember that CFCs are used in the propellant to help deliver the medication, not in the medication itself. CFCs and the Ozone Layer

The Environmental Protection Agency (EPA) has studied the effects of CFCs on the ozone layer of the earth’s atmosphere. In 1986, an international meeting was held and 26 countries signed a document called the “Montreal Protocol on Substances that Deplete the Ozone Layer Treaty.” Because of its importance, over 100 additional countries have also signed it. This international treaty calls for the use of CFCs to be phased out completely. This has already occurred in things like automotive air conditioning and aerosol household products. However, the EPA has granted an “essential use exemption” to products that are crucial to health and safety, allowing them to continue to be manufactured, at least temporarily. MDIs used to treat respiratory diseases, including asthma, are currently covered under this exemption. It is important that research continues and that alternatives to CFCs are found so that their use can be discontinued. The ozone layer is located 10 to 30 miles above the earth and is a powerful protective shield that protects us from the ultraviolet (UV) rays of the sun. (The ozone layer is different than the ozone that is caused by smog and pollution and is often a cause of asthma symptoms.) Too much exposure to the sun’s rays have been shown to cause skin cancer, which is increasing by a rate of approximately 4% each year. In addition, excessive UV rays have been linked to the development of

cataracts, immune disorders, and slowed crop growth, and they kill plankton, an important oxygen and food source in the oceans. The ozone layer is very thin; it is only about the thickness of five pennies. It is thinning, which allows more ultraviolet rays to reach the earth, and scientists have also discovered a hole in this protective shield over the earth’s South Pole. (See the image on the following page that shows measurements of the ozone layer.) CFCs have a long life span Each inhaler containing CFCs has and will continue to cause the potential to destroy one ton of damage even after they are no t h e e a rt h ’s ozone over its lifetime. longer used. Over the years, these CFCs withstand the eleis working together with the Food ments, such as wind and rain, and and Drug Administration (FDA) to rise high into the atmosphere. The ensure that CFCs for this use remain chemicals in CFCs stay together available as long as necessary. But until they are exposed to the sun’s remember: this essential use is only ultraviolet rays that cause them to temporary. It is vital for CFCs as a split. The chlorine in them binds propellant to be phased out to prewith the ozone and destroys it. One vent further damage and to allow the single chlorine atom has the ability ozone layer to recover. to destroy approximately 100,000 The development of CFC-free ozone atoms. Currently, it is believed MDI technology is underway. Today that the damage that has already there are three MDIs that contain a occurred will take until the year new propellant: hydrofluoroalkane 2045 to recover. Each year MDIs (HFA). The medications available in release about 6,750 metric tons of these inhalers are albuterol and ozone-damaging molecules into the beclomethasone. The medications are atmosphere. The CFCs are inhaled the same as in traditional inhalers, into the lungs but re-emitted into and they work in the same manner. the air when a patient exhales. Each There are actually advantages to CFC inhaler has the potential to destroy one ton of ozone over its life- these new HFA inhalers. They have a softer and warmer puff that may time. cause less throat irritation and A Thoughtful Transition cough. This is beneficial for the 20% to New Inhalers of people who experience what is CFCs for use in MDIs are the called “cold freon effect.” The cold only exemption where the EPA confreon effect causes some people to tinues to receive essential use applica- actually stop breathing or cough tions each year. The EPA recognizes when they inhale the medication the importance of the inhaled medreleased from a CFC inhaler. This is ications containing CFCs in treating because the medication is released at asthma and other respiratory diseases a temperature of about 29° F. In and is committed to protecting the contrast, the new HFA inhalers health of patients who require this release their medication at about medication. To ensure this, the EPA 57°F. HFA inhalers are also more staASTHMA MAGAZINE

to subscribe call 1.800.654.2452

|

29

Global imaging of ozone levels of the atmosphere using Total Ozone Mapping Spectrometer. The pink tones represent an ozone thickness of 150-225 Dobson Units, about the thickness of two pennies. Courtesy of Goddard Space Flight Center, NASA

ble and remain as a gas at lower temperatures. This allows them to work in colder temperatures, which is beneficial for people who live in colder climates or exercise in cold weather. When a traditional MDI is not used for a long period of time, it experiences “loss of prime,” requiring that you shake it and then depress the inhaler into air at least twice to ensure that there is adequate medication mixed with the propellant. This results in wasted medication. Inhalers containing HFA do not loose their prime as quickly. The final advantage to HFA inhalers is that they do not have what is called “tail-off.” This means that the first puff and last puff of medication in the canister will contain the exact same amount of medication. In CFC inhalers, after taking the number of doses stated on the canister, such as 200, you may still be able to depress the canister and have something be released, but the last few puffs (over the stated amount) may not contain the correct amount of medication. It is therefore very important to count doses of medication when you use an inhaler that contains CFCs. 30

|

ASTHMA MAGAZINE

In addition to inhalers containing the propellant HFA, other CFC-free delivery systems are available and new ones are being developed. These include dry powder inhalers, in which a number of medications are available, and nebulizer medications. These delivery systems use different techniques to deliver the medication into the airways safely and effectively, and they have been widely accepted by patients. Remember that it is important to know how to take your medication. Ask your healthcare provider or pharmacist to show you the proper technique and also how to care for your medication’s delivery system. When Will CFC Inhalers be Phased Out?

To accomplish a safe transition to CFC-free medical devices, the FDA has published a notice that outlines the criteria it will use to determine when and which CFC-containing MDIs will no longer be deemed essential use. Under this proposal CFC-containing medical products would be considered for phase-out once: • acceptable treatment alternatives exist;

November/December 2002

• adequate production of these medications is in place; • a year of post-marketing data on the alternatives reveals patient acceptance; and • it is determined that all significant subpopulations (such as children and pregnant woman) are served by the alternative products. Traditional MDI products will not be removed from the market until all four criteria have been met. (For more information, see the EPA’s Ozone Depletion Rules & Regulations, available at www.epa.gov.) In addition, the EPA is working with public health agencies and patient groups to educate patients and health care providers about this transition and the serious consequences of continued ozone depletion. It is important for you, the patient, to remember that it is the medication, not the delivery system, that treats your asthma or other respiratory disease. In order to protect the ozone layer that is so vital to mankind, this phase-out must take place. Change is never easy, but you may find these new delivery systems are just as good, or even better, than what you have used in the past. Keep an open mind and talk to your healthcare provider or pharmacist. All of us must do our part to ensure that the depletion of the ozone layer stops and that we allow it to recover. Change is a small price to pay to protect our earth and all of us from overexposure to the harmful rays of the sun. This change will help protect each of us and future generations. Suzanne Rutkowski, CMA, works as a patient educator, advocate, and consultant inthe fields of asthma and allergy. Reprint orders: Mosby, Inc., 11830 Westline Industrial Dr., St. Louis, MO 63146-3318; phone (314) 453-4350; reprint no.: 78/1/130162 doi:10.1067/mas.2002.130162