Complementary and alternative medicine remedies in the treatment of oncological patients – possible adverse effects and interactions with drugs: a literature review

Emilija Jacevičiūtė1, Rūta Minelgaitė1, Sigita Liutkauskienė2

1Faculty of Medicine, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania

2Department of Conservative Oncology, Hospital of Oncology, affiliate of Hospital of Lithuanian University of Health Sciences Kaunas Clinics, Kaunas, Lithuania


Herbs and dietary supplements are commonly used by oncological patients. There often is a lack of scientific evidence on the benefits of these remedies, on the contrary, adverse effects and interactions with medications may cause harm.

Aim. By analyzing scientific literature, to summarize and describe possible adverse effects and interactions with drugs that occur in oncological patients who use herbs or dietary supplements.

Materials and methods. Literature sources were selected from “PubMed”, “ScienceDirect” databases. Furthermore, information was researched in the “Natural Medicines” database of the Therapeutic Researcher Center. Most of the reviewed publications were no older than 10 years.

Results. High intake of licorice suppresses the inhibition of the adrenal–pituitary axis. Cases of hepatotoxicity of kava and chaparral have been reported. QT prolongation is associated with the intake of cesium chloride. Laetrile causes systemic toxicity. Aloe may cause hyperkalemia when interacting with anticancer drugs. Ginkgo, echinacea, milk thistle, garlic, Chinese ginseng, St. John’s wort interact with substrates of certain cytochromes. Green tea possibly interacts with bortezomib and imatinib. Herbs and dietary supplements, including ginkgo, fish oil, Chinese ginseng, ginger, turmeric, may interact with medications that affect clotting function.

Conclusion. Most herbs and dietary supplements which are used by cancer patients may have various adverse effects and interactions with prescribed medications. Therefore, after evaluating the patient’s willingness to use complementary and alternative medicine measures, the physician should be able to provide information on the potential benefits and harms of these substances.

Keywords: herbs, dietary supplements, cancer, interactions, adverse effects.