Complementary therapies: What is the evidence?

Conventional  cancer treatments have been through a rigorous testing process to see how safe and effective they are. New treatments are first tested in laboratories and then on large groups of people in what is called a clinical trial.

The strongest evidence comes from clinical trials that involve two groups of people. One group is given the new treatment and the other group is given the existing standard treatment. The two groups are compared. The results are looked at by independent experts (peer-reviewed)  and published in medical journals. If the new treatment works better than existing treatments, it may become the new standard treatment. This process provides the scientific evidence for the treatment.

With the increasing use of complementary therapies, many are now being scientifically tested to see what effects they have on people with cancer, how they interact with conventional treatments and why they might be effective.

Many of these tests have explored whether complementary therapies and medicines are effective in reducing specific symptoms to help people feel better during and after conventional cancer treatment. Some therapies are supported by strong evidence, while others lack rigorous scientific evidence.

Many alternative therapies and medicines have not been scientifically tested, or they have been tested and shown not to work or to be harmful to people with cancer. Some alternative practitioners promote their therapies and medicines as a cure for cancer, and encourage people to stop using conventional cancer treatment. If this is something you are considering, discuss this with your doctor first.

Alternative therapies can be expensive, and they are not covered by Medicare or the Pharmaceutical Benefits Scheme (PBS – a government-funded  scheme that subsidises some prescription medicines). It is important to consider the cost of these therapies if you are thinking about using them.

Cancer Council does not recommend the use of alternative therapies as a treatment for cancer. Only complementary therapies that have been proven to be safe to use alongside conventional cancer treatments.

Call Cancer Council 13 11 20 for a free copy of Understanding Clinical Trials and Research.

Complementary vs alternative

The terms ‘complementary’ and ‘alternative’ are often used interchangeably, which can be confusing. Complementary therapies are designed to be used alongside conventional cancer treatments, usually to manage side effects. Alternative therapies are used instead of conventional treatment. Many complementary therapies are being scientifically researched for use in people with cancer, while alternative therapies are unlikely to be tested in this way.

Safety of alternate therapies

Keep the following warning signs in mind if you are thinking about using an alternative cancer treatment instead of conventional medicine:

  • The practitioner does not have a qualification from an accredited educational institution in the therapy they provide.
  • The practitioner is not registered with a governing body or a professional association.
  • The practitioner tells you that conventional medical treatment will stop the therapy or remedy they provide from working.
  • The practitioner asks you not to talk to your doctors about their treatment, or won’t tell you the ingredients that make up a herbal preparation they give you.
  • The practitioner claims that their treatment cures cancer.
  • The practitioner says there are clinical studies for the effectiveness of their remedy or therapy, but does not show you proof that has appeared in trusted medical journals.
  • The treatment costs a lot of money or you need to pay in advance for several months’ supply of a remedy.
  • You need to travel overseas to have the treatment.

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This information was last reviewed in May 2015
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