The dangers of mixing medication

October 2004

Combining complementary medicines with prescription medication is becoming more and more common - but it can also be dangerous, Monash University pharmacy practice researchers warn. Ingrid Sanders reports.

Hidden dangers: Mr Johnson George and Dr Kay Stewart say doctors and pharmacists need to know what patients are taking. Photo: Melissa Di Ciero

Popping a multivitamin tablet or swallowing a herbal remedy while taking prescription medication is a common practice - and particularly prevalent among older members of the community.

But concealing this information from health practitioners can prove dangerous for certain people, says senior lecturer Dr Kay Stewart from Monash University's Victorian College of Pharmacy. Her doctorate student, Mr Johnson George, recently completed a study on the use of complementary medicines by chronic obstructive pulmonary disease patients.

"For the majority of people who complement their prescription medication with medicines such as multivitamins, minerals and herbal preparations, there is no risk," Dr Stewart says.

"But for some, there may be problems caused by mixing different types of medication. The reality is that some complementary medicines can cause problems in certain circumstances - for example, there have been reports of patients with asthma having severe reactions to royal jelly."

Mr George's study on the use of such medicines by chronic obstructive pulmonary disease patients found that a significant number were taking extra medicines without their doctor's knowledge.

"Almost half were using something other than their prescribed medication. The most commonly used were vitamins, minerals, garlic tablets and other herbal preparations, which are readily available from health food shops," Mr George says.

"Often patients with this condition have multiple health problems that require a range of prescription medications, but adding a mix of complementary medicines could jeopardise these patients' safety because of interactions between products."

Mr George said while the patients did not expect anything magical from the use of complementary medicines, they also did not believe they did any harm.

"But just because medication comes from a plant and is natural, it doesn't necessarily mean that it is safe," he says.

Dr Stewart says the research demonstrates the importance of patients consulting with a pharmacist or doctor before buying off-the-shelf medication.

"Health professionals can cross-check and by consulting them first, people can make sure the complementary medicine - whatever it may be - will be suitable to take in conjunction with their prescription medications."

Likewise, it is equally important for doctors and pharmacists to actively inquire about what complementary medicines the patient is taking and be open and accepting of this fact, she says.

"Our research shows that some patients feel they will be talked out of taking complementary medicines by health professionals so they deliberately hide the information," she says.

"But we know complementary medicines are widely used, so doctors and pharmacists can't simply forget about it. Instead, we need to encourage an environment where patients are comfortable talking about it and then doctors can make sure their patients are using them in the best way.

"We need more information and hard evidence about the efficacy of complementary medicines to help mainstream health professionals have a better understanding and knowledge about their use."

Action
Contact Dr Kay Stewart on +61 3 9903 9618, email kay.stewart@vcp.monash.edu.au, or Mr Johnson George on +61 3 9903 9057, email johnson.george@vcp.monash.edu.au.