Defining complementary medicines

Complementary medicines are hard to define and mean different things to different people.

One term is ‘complementary and integrative health’, which means the use of complementary approaches in combination with conventional medicine.

Alternative health is another term and means the use of complementary approaches in place of conventional medicine.

The National Center for Complementary and Integrative Health (NCCIH) advises against using any complementary product or practice that has not been proven safe and effective as a substitute for conventional medical treatment.

NHS prescribing

Most complementary medicines are not prescribable on the NHS.

NHS England has issued guidance on items which should not be routinely prescribed in primary care and this includes homeopathy and herbal treatments.

Safety

The main safety concerns when using complementary medicines relate to:

• limited robust evidence of efficacy
• side effects
• interactions
• lack of product regulation

Concerns about the evidence

Most clinical studies involving complementary medicines are of poor quality. No firm conclusions can be made from their outcomes.

Some complementary medicines are thought to have clinical efficacy, but this is not well researched. It is not possible to predict all the clinical or toxic effects.

In 2017, NHS England said it would no longer fund homeopathy on the NHS due the lack of any evidence for its effectiveness.

Reporting side effects

Any side effect involving the use of complementary medicines should be reported to the MHRA through the UK Yellow Card reporting site.

The site also contains reports made for some named herbal medicines such as cod liver oil and echinacea.

Incidence of interactions

The incidence of interactions between herbal medicines and conventional medicines is unknown. We often only know about them through published case reports.

Most interaction data refer to the potential interaction between one herbal ingredient and one conventional medicine. It is not possible to extrapolate this information to evaluate the effect of multiple herbal medicines on single or multiple conventional medicines.

The evidence base for interactions between herbal medicines and conventional medicines is often of poor quality and small scale. Many are theoretical interactions based on pharmacokinetic and pharmacodynamic interactions in isolation.

The lack of published interaction data for a herbal medicine does not mean there is no potential for an interaction in practice.

Licensing and registration

Not all complementary medicines available in the UK are regulated by the Medicines and Healthcare products Regulatory Agency (MHRA).

Product Licence

Complementary medicines carrying a UK Product Licence (PL) number will comply with some quality standards.

More information can be found on our page explaining the licensed status of medicines.

Traditional Herbal Registration

Complementary medicines carrying a Traditional Herbal Registration (THR) mark will comply with some of the safety and manufacturing standards applied to medicines.

Claims made by THR products are based on traditional use and not on evidence of clinical effectiveness.

Food supplements

Advising on food supplements should include the following points:

• most people do not need supplements and can get them from a balanced diet
• the NHS provides advice on eating a balanced diet
• taking vitamins or minerals at daily doses near to the Reference Nutrient Intake (RNI) are unlikely to cause side effects or interactions
• taking multiple combination supplements or high dose supplements may cause side effects or interactions
• there may be interactions with narrow therapeutic index medicines such as warfarin

Department of Health and Social Care (DHSC) advises vitamin and mineral supplements for some groups of people who are at risk of deficiency e.g. 400micrograms folic acid during first 12 weeks of pregnancy, 10micrograms vitamin D daily due to low sun exposure.

Regulation

Food supplements are not classed as medicines. They are made to a different quality standard to conventional medicines. Manufacturers are not required to comply with the manufacturing practices used for conventional medicines.

Dietitians must be registered with the Health and Care Professions Council (HCPC) to practise in the UK.

Homeopathy

Homeopathy is based on the use of highly diluted substances.

Advising on homeopathy should include the following points:

• there is no good quality evidence that homeopathy is effective treatment for any health condition
• their effects are considered to be like a placebo
• Homeopathic Registration (HR) marked products are unlikely to cause side effects or interact
• uncertified products may contain undeclared ingredients which could cause side effects or interact

Regulation

Homeopathic products must be registered to one of the following schemes:

• Product Licences of Right (PLRs) where products can include indications for use
• Simplified Registration Scheme where products are not allowed to include indications for use
• National Rules Scheme where products can be granted a marketing authorisation for the relief or treatment of mild, self-limiting conditions (without the supervision or intervention of a healthcare professional)

Under each scheme, products must meet standards of safety and quality but are not required to demonstrate efficacy.

The MHRA lists products that have an HR certificate.

There is no legal regulation of homeopathic practitioners in the UK.

Chinese Medicines

Traditional Chinese Medicine (TCM) is a mixture of herbal medicines and non-medicinal approaches such as tai chi and acupuncture.

Advising on TCM should include the following points:

• studies are generally of poor quality
• some have been found to contain undeclared ingredients such as warfarin, NSAIDs and steroids
• some have been found to contain toxins such as arsenic, lead, pesticides and sulphites
• they are likely to have side effects and interactions
• they are included in any list of medicines taken

Regulation

The MHRA does not regulate TCM. However, some TCM may carry a THR mark.

There is no legal regulation of TCM practitioners in the UK.

Ayurvedic medicines

Ayurvedic medicine is an Indian medical system that combines mainly herbal medicines, diet, exercise and lifestyle.

Turmeric is commonly used as a herb in Ayurvedic medicine.

Advising on Ayurvedic medicine should include the following points:

• there are limited well-designed reviews that support their effectiveness
• some have been found to contain potentially harmful levels of metals such as lead, mercury, arsenic, and minerals
• they are likely to have side effects and interactions.
• they are included in any list of medicines taken

Regulation

The MHRA does not regulate Ayurvedic medicines. However, some may carry a THR mark.

There is no legal regulation of Ayurvedic practitioners in the UK.

Herbal medicines

Herbal medicines are plant derived and include the leaves, roots and flowers. They are also sometimes called botanicals.

Advising on herbal medicines should include the following points:

• there are limited well-designed reviews that support their effectiveness
• they are likely to have side effects and interactions
• some have been found to contain toxins and contaminants
• when purchasing herbal medicines to look for the THR mark
• they are included in any list of medicines taken

Regulation

Herbal medicines intended for conditions that can be self-medicated without any medical supervision may carry a THR mark.

Some herbal ingredient are banned or have restricted use in the UK due to concerns about safety.

There is no legal regulation of herbalists in the UK.

General advice

When advising on the purchase of a complementary medicine, healthcare professionals should advise the public to:

• refer to the MHRA Fake Medicines campaign
• look for a PL number on the product label
• look for the THR registration
• use a reputable source
• avoid online sources that are not registered pharmacies due to the risk of fake medicines
• not switch brands or products