Why Herbal Remedies Can Be 'Dangerous' For Cancer Patients Undergoing Treatment

These remedies aren't the only issue – cancer specialists are warning against taking a range of alternative therapies.
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Herbal remedies may seem like a good option when you’re trying to look after your health through cancer, but a breast surgeon has warned that some of them could do more harm than good.

Speaking at a cancer conference in Lisbon, Professor Maria João Cardoso said there’s a long list of herbal products and creams that patients often try, but many of them could interfere with recovery. Some, for example, delay wound healing, while others can hinder hormone therapy or chemotherapy.

Prof Cardoso said it’s “very important” that patients check with their doctors before trying complementary treatments, especially if their cancer has spread to the skin. “There are many of these therapies, especially herbal products and topical creams, that can have a negative impact in cancer treatment,” she said.

Martin Ledwick, Cancer Research UK’s head information nurse, reaffirmed Prof Cardoso’s comments, adding that these therapies can be “dangerous” for cancer patients.

“They could interfere with any treatment someone is undergoing, reducing its effectiveness or causing patients harm, or people could choose them instead of conventional medicine,” he told HuffPost UK.

There’s “no strong evidence” that herbal remedies can treat, prevent or cure any type of cancer, he added. Ledwick said patients shouldn’t use any alternative therapies that haven’t been approved by their cancer specialist doctor.

So which ones should you be avoiding?

Laboratory studies have shown that certain remedies can reduce the blood clotting process required for a wound to heal – in patients whose cancer spreads to the skin, lesions can form and be very painful and distressing. “If a patient has a bleeding wound, these compounds can have a strong, adverse impact on scarring and how well wound dressings work,” said Prof Cardoso.

Natural remedies that can impact clotting include:

:: Green chiretta

:: Feverfew

:: Garlic

:: Ginger

:: Ginkgo

:: Ginseng

:: Hawthorn

:: Horse chestnut

:: Turmeric

The list above features just some examples. The number of herbal products available is huge and the evidence for their efficacy is nil, said Prof Cardoso.

Some herbal supplements can also “harmfully interfere” with chemotherapy treatments, according to Ila Saunders, an assistant clinical professor at the University of California San Diego. Echinacea, curcumin, St John’s wort, valerian root, and allium (an extract of garlic) are all examples of herbal remedies that can disrupt the toxicity-efficacy balance of chemotherapy.

And while it’s not a herbal remedy, another alternative therapy is fruit juice –Shamir Patel, of Chemist 4 U, said there are “irresponsible” claims that drinking citrus juice can boost the effectiveness of cancer drugs. “In reality, drinking grapefruit juice excessively whilst taking these drugs can be harmful for patients,” he said.

“Not only can this lead to side effects such as diarrhoea and loss of appetite, this juice also inhibits CYP enzymes that break down certain drugs. This can be dangerous – they are essentially increasing the concentration of the drug, which means the patient is effectively taking a higher-than-intended dose.”

Ultimately, if you’re taking herbal medicines or alternative therapies in addition to your cancer treatment, you need to speak to your oncologist about it right away. “The highest goal in medicine is important to remember: do no harm,” Prof Cardoso concluded.

There are some therapies which could help with the psychological impact of cancer and have a positive impact, she added. These include using mindfulness to reduce stress, acupuncture, Reiki and yoga.

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