A study being published in the Feb. 24 issue of American Journal of Obstetrics and Gynecology determined that that health care providers need to spend more time asking about medication usage.
"We really need to inquire better about patients taking herbal and over-the-counter medications," says Timothy Tracy, Ph.D., a professor at the University of Minnesota College of Pharmacy, the University of Minnesota Center of Excellence in Women's Health and one of the article's authors. "The care providers need to ask, and patients need to tell. Neither one is doing a good job."
Among the more than 570 study participants, 92 percent took prescription medications, and 96.5 percent self-medicated with an over-the-counter medication. Furthermore, 59.1 percent of study participants used herbal supplements.
Researchers also found patients may not mention medications to the physician unless that physician had prescribed the drug. For example, patients did not always tell the gynecologist they were taking high blood pressure medication prescribed by another physician.
"Patients may not perceive that their blood pressure medication was something their gynecologist needed to know about," Tracy says. "Sometimes, patients don't associate their disease and medication with the individual physician they're seeing at any given time if the physician is not the one treating that condition or if they didn't prescribe the medication."
Pharm.D. students interviewed study participants using a three-step process. Patients were asked open-ended questions about what mediations they take. The interviewer then conducted a system-by-system analysis, asking patients whether they took any medications for situations such as headaches, upset stomachs or achy joints. The patients were then presented with a list of common mediations--including prescription, over-the-counter, vitamins and herbal supplements--and asked whether they took any of those medications.
Researchers found that every set of questions uncovered additional medications patients didn't initially report. They also discovered that while a patient may report that she's taking a medication during the first visit's interview, she failed to mention it on subsequent visits without prompting.
The interviews were conducted during a 42-month period. During the study, 567 patients had 776 interviews. Patients who had multiple visits during that time frame were interviewed multiple times. The interviews were conducted following women's visits to their gynecologist. Only nonpregnant women were interviewed.
Among the women who took prescription medications, 20 percent used more than one medication, and 39 percent took more than four medications. Of those interviewed, 97 percent took at least one over-the-counter medication, and 59 percent took more than four OTC medications.
The data also showed several potentially serious drug interactions. The most commonly prescribed medication was antibiotics, some of which are thought to reduce the efficacy of birth control pills.
Researchers also found that nearly 25 percent of patients took medications for anxiety, depression or other mental health issues. Of patients who used oral contraception, 2.3 percent took St. John's wort, which can reduce the efficacy of the birth control pill.
The study also found several women taking prescription antidepressants also self-medicated with St. John's wort, an herbal supplement commonly used to treat depression, which has been shown to have potentially harmful interactions with prescription antidepressants.
"Will this drug interaction kill you? Probably not," Tracy says. "Can you experience serious adverse effects? Yes."
The study was conducted in conjunction with colleagues in the obstetrics/gynecology clinics at West Virginia University.
The College of Pharmacy, the only school of pharmacy in Minnesota, offers its program on the Twin Cities and Duluth campuses. Founded in 1892, the College of Pharmacy educates pharmacists and scientists and engages in research and practice to improve the health of the people of Minnesota and society. The college is part of the Academic Health Center, which is home to the University of Minnesota's seven health professional schools and colleges as well as several health-related centers and institutes.
The Academic Health Center is home to the University of Minnesota's seven health professional schools and colleges as well as several health-related centers and institutes. Founded in 1851, the University is one of the oldest and largest land grant institutions in the country. The AHC mission is to prepare the new health professionals who improve the health of communities, discover and deliver new treatments and cures and strengthen the economy.
Journal
American Journal of Obstetrics and Gynecology