Managing meds can prevent drug interactions


Jane Mitchell takes four different prescription drugs each day.

She takes one for blood pressure, one for cholesterol and one for osteoporosis. Then she takes another pill to treat heartburn the latter medication causes.

This four-drug combination is safe on its own. But throw in some grapefruit juice, too much alcohol or the wrong antibiotic, and a negative drug interaction could cause Mitchell, 71, to feel dizzy and fall, damage her kidneys or cause severe pain.

These and other potentially fatal combinations of prescriptions, over-the-counter medications, food and dietary supplements are part of a major public health problem sending thousands of seniors to emergency rooms each year, according to a 2012 study published in the New England Journal of Medicine.

“Luckily, I’ve never had any trouble with that,” said Mitchell, who knew grapefruit juice would be a problem with her cholesterol medication because she used to work in health care.

Still, the retired physical therapist wishes there was a broad-based alert system that would raise a red flag if she got a prescription that might put her at risk for any of these issues.

Nearly 29.8 million people 65 or older are taking more than three prescription drugs each day, according to a recent report from the Centers for Disease Control and Prevention. That figure includes 17.5 million seniors who are taking five medications each day.

There is a system in place to prevent a negative drug interaction if a person uses one pharmacist consistently. Some pharmacies work with insurance companies to learn about all the medications a person is taking, but that’s limited by information available from available insurance and pharmacy records.

Knowing the dangers of negative drug interactions, however, falls heaviest on a patient.

“Ask questions and reach out for help,” said Michael Taday, the director of pharmacy professional practice and clinical operations with Humana, Oregon’s largest Medicare Prescription Drug Plan provider, serving nearly a fourth of the state’s Part D enrollees. Taday urged seniors to be proactive in their medication management. “Don’t assume your pharmacist and your physician knows what the other is doing.”

The risks

According to the AARP/HealthLine drug interaction checker, Mitchell’s blood pressure medication, lisinopril, could cause her to feel dizzy if she drinks too much alcohol while taking it.

Her cholesterol medication, simvastatin, can cause severe muscle aches and fatigue if it’s mixed with more than a quart of grapefruit juice each day. It also can damage her kidneys and cause her muscle tissue to break down if mixed with a macrolide antibiotic like clarithromycin or erythromycin.

Negative drug interactions and other incidents and injuries stemming using medication as prescribed sends 77,853 seniors to the emergency room each year, according to the NEJM study. A third of these patients suffered symptoms so severe they stayed in the hospital for more than a day.

“It’s definitely something you worry about and something you see,” said Rob Uetrecht, staff pharmacist at the St. Charles Health System’s community pharmacy.

These problems often happen with seniors because a person’s metabolism, liver and kidney function slows down considerably as they age, Uetrecht said. This means it takes longer for a medication to clear their system, and a normal dose of medication could push them over the edge to overdose territory.

Seniors are also more likely to take more than one prescription drug or a combination of prescription drugs, over-the-counter medications and dietary supplements, studies show.

Any one of these medications could cause a negative drug interaction if a new prescription comes on board, he said. This problem is only made worse by the fact many seniors do not tell their doctors about every medication they take because they forget one or might not think it’s important at the time.

For instance, forgeting to tell you doctor you take Sudafed during allergy season could lead to nervousness, irritability, difficulty sleeping, increased blood pressure and seizures if he gives you a prescription for Welbutrin.

“When we fill prescriptions for patients,” he said, “we have to watch for all kinds of different things.”

The system

Federal law takes a stab at preventing adverse drug reactions by requiring pharmacists to put detailed information about a medication’s proper dosage, potential interactions and other side effects with every prescription they fill.

They must also put brightly colored labels on a drug’s bottle that warn about any interactions it has with alcohol, aspirin, acetaminophen or another commonly-used OTC medication. Those same warning labels let people know to stop taking a medication if they become pregnant, talk to their doctor before they take any other forms of medications and seek immediate medical attention if certain side effects should arise.

There is a lot of information available about a patient’s drugs,” Taday said. This information is also featured on websites managed by AARP, the National Institutes of Health and private companies such as Drugsite Trust.

Insurance companies that provide Medicare prescription drug coverage must also talk to certain members about the medications they are taking and help them come up with a long-term medication management plan. The criteria for these conversations vary widely from prescription plan to prescription plan, Taday said, explaining they tend to focus on how many drugs the member is taking, how many chronic conditions he or she has and how much money the person might spend on drugs each year.

Finally, pharmacists who work with Humana insurance companies pool their prescription and claim information into a database that can track an individual patient’s drug use over time. These programs throw up a red flag when the pharmacist fills a prescription that may have a negative interaction with something the patient is taking or has taken in the past, Uetrecht said. He shares this information with the patient’s physician so a medication regimen or dosage can be changed if need be.

“We’re constantly sending notes to doctors,” Uetrecht said. “First and foremost, my thought is, ‘Am I doing harm to the patient by letting him have the medication?’”

But these systems also have holes.

Pharmacies only have records about prescriptions they fill, and insurance companies only have records if there’s a claim, Taday said. This means some medications may fall through the cracks if a patient uses more than one pharmacy, pays for a prescription out of pocket or takes an over-the-counter medication or a supplement that does not require a claim.

That’s why it’s important for patients to talk to their doctors and pharmacists about every medication they take, he said, or make sure they have a caregiver or a friend who can do so in their place.

“A patient who stays engaged with their medication management is critical,” 

This article was originally published in The Bulletin on Oct. 23, 2015