Safety of Intravenous Mistletoe (Viscum album) in Oncology

Safety of Intravenous Mistletoe (Viscum album) in Oncology

Mistletoe (Viscum album) preparations are widely used in some integrative oncology settings, primarily as supportive therapy aimed at improving tolerance to cancer treatment and overall well-being. Steele and colleagues conducted an observational study to evaluate the safety of intravenous mistletoe administration in patients with cancer.
In this study, oncology patients received intravenous mistletoe extracts in a clinical setting, and researchers systematically recorded adverse events, dosing patterns, and treatment tolerability. The focus was on assessing short- and medium-term safety outcomes rather than anti-cancer efficacy. Patients included a range of cancer types and disease stages, reflecting real-world use in integrative oncology practice.
The results indicated that intravenous mistletoe was generally well tolerated. Most reported adverse effects were mild to moderate and included transient flu-like symptoms such as fever, chills, fatigue, and local infusion-related reactions. Serious adverse events were rare and not consistently attributed to the mistletoe treatment. Overall, the safety profile was consistent with expected immunomodulatory effects.
Although this was an observational study without a control group and not designed to evaluate survival or tumor response, it provides real-world safety data supporting the tolerability of intravenous mistletoe preparations in oncology patients. These findings contribute to the evidence base informing its use as a complementary supportive therapy in cancer care.

Reference:

Steele ML, Axtner J, Happe A, Kröz M, Matthes H, Schad F. Safety of intravenous application of mistletoe (Viscum album L.) preparations in oncology: an observational study. Evid Based Complement Alternat Med. 2014;2014:236310. doi:10.1155/2014/236310. PMCID: PMC4052504.