GAINESVILLE, Fla. --- When an asthma attack strikes, leaving a child breathless and wheezing, many parents have to scramble to plug in the device that supplies medication to ease the respiratory disease's symptoms.
Although the electronic nebulizer has long been favored by practitioners, University of Florida clinical pharmacist Leslie Hendeles wants parents and physicians to know they have another option - a device that cheaply and effectively delivers asthma medicine in a fraction of the time, without the need for electricity and with fewer side effects.
A metered-dose inhaler, or MDI, is the small pressurized canister the public commonly associates with the treatment of adult asthma patients. It requires patients to press down on the device and inhale as the medication is released, then hold their breath for 10 seconds.
The inhaler system Hendeles recommends is a modification of the MDI and is designed to make delivering treatment easier for children - and even some adults - who often have difficulty timing the medication's release as they inhale. During the two-minute treatment, a puff of medication is released into an attached holding chamber in 30-second intervals, and the patient breathes in the medicine through a mask, similar to the nebulizer's mask.
Hendeles says many physicians have been slow to recommend the chamber attachment for young children. That's because of the common misperception that the electronic nebulizer is more effective at delivering medication, he says, even though it requires assembly, cleaning, up to 20 minutes to complete the treatment and a power source such as an electrical outlet or a car lighter. The nebulizer is driven by compressed air and converts liquid medicine into a fine mist that is inhaled.
"The basic message I am trying to get across to pediatricians and family physicians is that the common misbelief that the nebulizer is more effective is just not right. And that physicians can make it more user-friendly for the parents to administer the medications, so that children will get back to playing faster," says Hendeles, who has been studying asthma medications for 25 years and is a professor of pharmacy and pediatrics at UF's colleges of Pharmacy and Medicine.
At the American Academy of Family Physicians' Scientific Assembly in Dallas on Wednesday, Hendeles encouraged health-care providers to recommend the modified MDI over the nebulizer for most patients, including infants.
A decade of research has shown the modified inhaler system is just as effective as the nebulizer for administering quick-relief medicines. In 1993, UF researchers, including Hendeles, published findings in the American College of Chest Physicians' journal Chest demonstrating that the drug albuterol for the treatment of a sudden asthma attack was equally effective when it was given by nebulizer or inhaler. Ninety percent of asthma patients use albuterol to relieve acute symptoms.
According to the National Institutes of Health, more than 14 million people in the United States - including 5 million children - have the respiratory disease.
The inhaler system also is used with young children to administer medications such as inhaled steroids, taken on a regular twice-daily basis to prevent asthma symptoms, even when the patient is symptom-free. UF researchers currently are evaluating how well inhaler systems deliver preventive medication and how much gets into the bloodstream in children.
In addition to its convenience, the inhaler system offers other advantages. When a nebulizer is used, a child often swallows a lot of the medicine, causing it to be absorbed into the bloodstream. This can lead to an elevated heart rate, tremors and agitation. With the inhaler system, very little of the medication gets into the bloodstream, so there are fewer side effects.
The MDI with the attached chamber also is cheaper. It costs $20 to $50; the nebulizer system costs approximately $150. Each dose of medicine administered through the MDI system costs about 5 cents, while an equivalent dose given through the nebulizer costs about 25 cents. Overall, side effects are not as common with the inhaler and it enables patients to use less of the drug, Hendeles says.
As with the nebulizer, there are potential problems with the inhaler system. Children may remove the mask or they may be upset and unwilling to cooperate. Although Hendeles encourages the use of the inhaler system for all children, he concedes that the nebulizer remains an option for children who will not cooperate.
"Sometimes nebulizer therapy delivers too much medication and leads to agitation and tremor rather than benefit," says Dr. Gail Shapiro, a clinical professor of pediatrics at the University of Washington School of Medicine and president-elect of the American Academy of Allergy, Asthma and Immunology. "But there are situations where children require high-dose therapy that is delivered best with a nebulizer, and there are children who will not comply with use of an MDI and (chamber attachment)."
Hendeles says even high doses of either quick-relief medicine or preventive medicines, such as inhaled steroids, can be given by the MDI and chamber attachment simply by increasing the number of puffs.
In addition, some asthma-relief medications inhaled through the nebulizer contain the preservative benzalkonium, which helps keep the solution sterile but actually constricts the airways, potentially decreasing the therapeutic response to the asthma-relief medication.
"The preservative, benzalkonium, can counteract the effects of the medicine, and the doctor and parents may not realize that this is the reason why the patient is not responding well," says Hendeles, whose research has been funded by various drug companies, none of which manufacture the modified inhaler's chamber attachment.
The drug-container component of the inhaler system, along with sterile nebulizer solutions, are designed so that they cannot be contaminated; therefore, there is no reason to use an albuterol product containing benzalkonium.
Hendeles says his efforts to teach physicians and patients about the alternatives stem from wanting to make the care of an asthmatic child as easy for parents as possible and more cost-effective for the health-care system.