Complementary medicines - tell your doctor

It is important to tell all your health care professionals about any complementary medicines you are taking. Complementary medicines include vitamin and mineral products, herbal medicines including Chinese and Ayurveda medicines, homeopathic preparations and essential oils.

The way some complementary medicines are applied or used needs to be considered because side effects may be caused by the way the medicine is used rather than the medicine itself. For example, some people who take anticoagulant medicines (blood thinners) after an essential oil massage have reported significant bruising. In this case it was most likely the massage, rather than the essential oils, that was the cause of the bruising.

Interaction with other medicines
People often think complementary medicines are safe and will not cause any problems. However, complementary medicines may cause side effects or interact with prescription medicines, alcohol and other drugs, and other complementary medicines to cause side effects. It is important to tell all your health care professionals about all the medicines you are taking, including prescribed medicines, over-the-counter medicines and complementary medicines.

Some complementary or alternative medicines can interfere with cancer treatments. If you are about to receive chemotherapy, talk to your oncologist or haematologist about any other therapies or medicines you are taking or thinking of trying. Tell other health professionals (for example, nurses or pharmacists) at your treatment centre before starting treatment if you are taking complementary medicines.

Why people don’t tell their health care professionals
About half the people who use complementary medicines do not tell all their health care professionals. The reasons include:

• Not thinking of complementary medicines as ‘medicines’
• Thinking that products promoted as ‘botanical’ or ‘natural’ are safe and not likely to cause side effects
• Believing their health care professionals are either not interested or will not understand why they use complementary medicines
• Feeling concerned their health care professionals will be judgemental or negative
• Believing that health care professionals have limited knowledge about the effectiveness and potential benefits and harms of complementary medicines
• Not being asked by their health care professionals about complementary medicines.

• The type and name of any complementary medicines you are taking
• How often you take the medicine and the dose
• The amount of active ingredient in each dose – it may be easier to bring the medicine with you (you need to use the botanical names of herbal medicines and essential oils to avoid confusion caused by the common names)
• How long you have been taking the medicine and why you are taking it
• The health benefits that you expect from taking the medicine
• Whether the medicine has worked for you.

• Echinacea – over 20 different types of side effects have been reported including asthma attacks, hives, swelling, aching muscles and gastrointestinal upsets.
• Feverfew – pregnant women are cautioned against using this herb because it can trigger uterine contractions. In animal experiments, feverfew was found to trigger spontaneous abortions (miscarriages).
• Asteraceae plants (from the daisy family) – which include feverfew, Echinacea, dandelion and chamomile. Side effects include allergic dermatitis and hay fever.

• Echinacea may interact with drugs broken down by the liver.
• Many complementary medicines – including feverfew, ginkgo and chamomile – may increase the risk of bleeding in people taking anticoagulant medicines such as warfarin and anti-inflammatory medicines such as aspirin.
• St John’s wort has caused breakthrough bleeding and unwanted pregnancy in women taking the oral contraceptive pill.
• St John’s wort increases serotonin. Taking St John’s wort at the same time as other medicines that increase serotonin (such as antidepressants) increases the risk of serotonin syndrome – symptoms include tremors, high temperature and low blood pressure and can range from mild to life threatening.

• Pregnant women, especially in the first trimester
• People with kidney or liver disorders
• People who are already taking prescription medicines, non-prescription medicines or other complementary medicines
• People taking multiple medicines
• Young children
• Older people
• People who are malnourished – for example, people with anorexia
• People who misuse alcohol or other drugs.

• In an emergency, call triple zero (000) for an ambulance
• Your doctor
• Nurses, especially specialist nurses such as diabetes educators or cancer nurses
• Pharmacists
• Other health care professionals, such as complementary therapists
• National Prescribing Service, Medicines Line Tel. 1300 888 763 – for information on prescription, over-the-counter and complementary medicines
• Adverse Medicines Events (AME) Line Tel. 1300 134 237
• Poisons Information Centre Tel. 13 11 26 – for 24-hour emergency advice, if you think someone has ingested (swallowed or taken into their body) a poison or taken an overdose
• Nurse-on-Call Tel. 1300 60 60 24 – for expert health information and advice (24 hours, 7 days)

• Complementary medicines can cause unwanted effects as well as beneficial effects.
• It is important to tell all your health care professionals about all the medicines you are taking including complementary medicines.
• Ideally, you should discuss the possible benefits and harms of using complementary medicines with your health care professionals before you start taking them.

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