Complementary and alternative medicine

The term complementary and alternative medicine (CAM) is usually used to describe a medical product or practice that's outside what is considered mainstream, conventional or traditional medical care.

When complementary medicine or practices are used together with conventional medicine, it's considered ‘complementary’. For example, using acupuncture to help with side effects of cancer treatment.

When complementary medicine or practices are used instead of conventional medicine, it's considered ‘alternative’. For example, using diet and herbal remedies for a condition instead of using recognised treatments for the condition.

CAM is also sometimes called:

• complementary and alternative therapy
• natural medicine
• herbal remedies
• non-conventional medicine
• holistic medicine.

Many different practices come under the term complementary and alternative medicine (CAM). The following table lists some examples. 

Many alternative treatments seem to work, but whether this is due to an actual clinical effect or belief that it will work (called the placebo effect – see below), is undecided. It's difficult to use scientific methods to check whether CAM has made a difference – only a few high quality studies of alternative therapies exist. 

The placebo effect

The placebo effect is a phenomenon in which a placebo (a fake treatment that contains no active ingredients) leads to improvement in a person's condition simply because the person expects that it will be helpful.

In a similar way, when the belief in the value of an alternative therapy is strong, this can account for the success of a treatment even if scientifically it may not be accepted. 

Other factors may lead to the success of CAMs

• People may get better due to the natural course of an illness and think this could be due to their alternative therapy.
• Many illnesses are cyclical and people often seek alternative therapy when symptoms are at their worst. When symptoms improve, this is attributed to the therapy.
• An alternative therapy may be tried after conventional medical treatment and, when symptoms improve, it's attributed to the new therapy rather than the medical treatment.
• If the original diagnosis is wrong, then claims of a cure are meaningless.
• The time and attention from the provider of alternative therapy may improve well-being.
• Alternative therapies may help to give hope.

Questions to ask

Before using CAM, talk with your doctor and other healthcare providers about it. Together you can discuss any benefits of using CAM,check interactions with your conventional medicine or treatment and any safety concerns. For example, some plants can interact with conventional medicines.

The sorts of questions that you and your healthcare provider may want to discuss include the following:   

• Is there clinical evidence of effect?
• Is it safe? You can check for warnings on natural and herbal products on the Medsafe(external link) website.
• Is it expensive? In Aotearoa New Zealand, the Accident and Compensation Corporation (ACC) funds acupuncture, chiropractic manipulation and osteopathy.
• Are there adverse effects?
• Does it interact with other medications?
• Will it compromise conventional medical treatment – make it work less effectively?
• Will it reduce the need for conventional medications?

As with any decision concerning your health, decisions about whether to use complementary approaches are important. The National Center for Complementary and Integrative Health (NCCIH), an American website, has developed information to help in the decision making about complementary health products and practices(external link).

Find out more information on the product or service

The following link provides further information on CAM products and services. Be aware that research from other countries may contain information that differs from New Zealand recommendations.

Cochrane is a global independent network of researchers, professionals, patients, carers, and people interested in health. Its contributors come from more than 130 countries and they work together to produce credible, accessible health information that is free from commercial sponsorship and other conflicts of interest. There are many Cochrane reviews on complementary and alternative products and therapies. Search the Cochrane database for evidence(external link) on CAM.

Lack of regulation

In Aotearoa New Zealand there is a Natural Health Products Advisory Group (external link)that advises the Ministry of Health on natural health products. Other than this, there is limited regulation of products or services through specific legislation or a single organisation that is responsible for ensuring the safety of all complementary or alternative medicine.

Herbal or natural products and dietary supplements may have safety concerns because of this lack of regulation for safety, effectiveness and quality. This is different to conventional medicines that undergo rigorous testing and must show safety and benefit before they are made available for public use.

In Aotearoa New Zealand, Medsafe(external link) reports adverse effects and interactions associated with herbal products and dietary supplements. It's not only the main ingredients that can be of concern, but other substances, eg, preservatives and other ingredients. These are known as excipients, read more about excipients in medicines(external link). An example from February 2024 is the cases of lead poisoning with Ayurvedic Medicines(external link). 

Registered health professionals must meet professional standards under the Health Practitioners Competence Assurance Act 2003. They must maintain their professional competence and can’t practice outside their area of expertise. 

While some practitioners of complementary and alternative medicine are registered health professionals, many are not registered. Those who are not registered are not subject to the Health Practitioners Competence Assurance Act 2003.