Distributing medications in specially designed blister packages rather than in bottles may increase the likelihood that medications will be taken properly

May 16 2005

Distributing prescription medications in specially designed blister packages rather than in bottles may increase the likelihood that medications will be taken properly, a new study suggests.

The study found that patients taking lisinopril – a medication used to treat chronic high blood pressure – were more likely to have their prescriptions refilled on time if the medication came in a blister package rather than as loose tablets in a bottle. In this case, the blister package clearly started the day on which to take each pill.

Moreover, diastolic blood pressure was reduced in nearly half of the patients who received the drug in a blister package, compared to fewer than 20 percent of those participants who received bottles of medication. Diastolic pressure measures the pressure of the blood between heart beats, while the heart is resting. In a typical blood pressure reading of 120/80, the diastolic pressure is 80.

“This suggests that a better system of packaging for medications helped people take their medications properly, said Philip Schneider, the study's lead author and a clinical professor of pharmacy at Ohio State University.

He presented the findings on May 16 in Washington , D.C. , at the American Heart Association's Sixth Scientific Forum on Quality of Care and Outcomes Research in Cardiovascular Disease and Stroke. Schneider conducted the study with Ohio State colleague Craig Pedersen, an associate professor of pharmacy, and with John Murphy, of the University of Arizona.

The researchers referred to the blister packs that were used in this study as “pill calendars.” Like traditional pill calendars – usually a plastic box with individual compartments that can hold pills to be taken each day of the week – these blister packs included the day that each dose was to be taken.

Blister packages are cards in which individual pills are put in small plastic bubbles, and then backed with foil. A person pushes on the bubble, forcing the pill through the foil to retrieve it. The card also has more room to print important information about the proper use of the medication.

Although putting medication in blister packs isn't a new idea – many short-term medications are distributed in such packages – most long-term medications are not packaged that way. (Birth control pills are one exception.)

The study included 88 adults who were 65 and older. All of the participants had hypertension, indicated by a blood pressure reading of 140/90 or higher, and were treated with lisinopril (brand name Prinivil) during the study.

More than half (48) of the participants were randomly assigned to receive a 28-day supply of medication in the blister package, while the rest of the patients (40) received a traditional bottle of loose tablets. The study lasted nearly two years, and participants were enrolled for 12 months each. During their time in the study, the patients saw their physician once every six months and their pharmacist about once each month for refills.

The researchers gathered information from pharmacy records that showed how often participants refilled their prescriptions. The researchers also collected blood pressure readings and information about the onset of diseases associated with hypertension from the patients' medical records.

Results showed that 14 percent more participants who received their medication in a blister pack with the pill calendar format had their prescriptions refilled on time. Also, the researchers noted that 48 percent of the patients in this group had lower diastolic blood pressure after 12 months, compared to only 18 percent of the patients who received their medications in a bottle.

While a few patients complained that the blister packaging was too difficult to open, no other adverse events were noted.

“If people can tell whether or not they have taken their medication on a particular day, it improves the chance that they will take the medicine properly,” Schneider said. “It's often hard to put all of the information a patient may need on to one container.”

About 50 million Americans have chronic hypertension, and most that do are 65 or older. If left untreated, the disease can cause a whole host of health problems, including changes in the blood vessels in the back of the eye, heart attacks, kidney damage and stroke.

“There often aren't any symptoms that signal high blood pressure,” Schneider said. “And medications like lisinopril that are given to treat the disease can have unpleasant side effects such as a dry, hacking cough, so adherence to treatment regimens is often poor.”

The findings may also have important political ramifications.

“As the federal government develops policies for the new prescription drug benefit for older adults, there is a need to consider how these medications are distributed,” Schneider said. “Although blister packs are slightly more expensive than a bottle, people often forget to take their bottled medications, or get confused on how to take them properly. Offering long-term medications in this type of packaging could ultimately save millions of dollars.”

Financial support for this work came from the Centers for Medicare and Medicaid Services. Merck & Co., Inc. provided the lisinopril, while Cardinal Health provided the blister packages used in the study.

http://www.osu.edu/