Not only do the side effects of rhodiola appear to be minimal, but some promising preliminary evidence suggests it may minimize the side effects of other potent medical therapies. Some of the most promising benefits of rhodiola involve its ability to act as an antimutagenic for other necessary but dangerously potent therapies, such as chemotherapy.

However, more studies need to be conducted to verify (or possibly refute) the promise of small, early pilot studies.

Rhodiola Rosea Antioxidant and Anti-carcinogenic Effects

Among the lesser known rhodiola benefits is that Rhodiola rosea is rich in phenolic compounds, known to have strong antioxidant properties.53,86

Animal studies have shown that Rhodiola rosea decreases toxicity from cyclophosphamide, rubomycin, and adriamycin (anti-cancer drugs), while it enhances their anticarcinogenic effects.87-89 Udintsev and Schakhov studied the effect of R. rosea root extract (RRRE), a tincture manufactured according to the Russian Pharmacopoeia standards (minimum 0.8 percent salidroside and 3 percent rosavin), on tumor cells (transplanted into mice) and normal bone marrow cells in two mouse cancer models.90 One group of mice with Ehrlich ascites tumor (EAT) and another group with Lewis lung carcinoma (3LL) were first treated with 100 mg/kg cyclophosphamide (a chemotherapy agent) that suppressed tumor growth to 31-39 percent and limited 3LL metastases to 18 percent, while also reducing the number of normal bone marrow cells, leucocytes, and myelokariocytes, to 40-50 percent and 20-25 percent of normal, respectively.

Promising Results of Giving Rhodiola Rosea

In comparison, RRRE, 0.5 mg/kg/day given orally 2-8 days after tumors had been transplanted, suppressed growth of both tumors by 19-27 percent and 3LL metastases 16 percent. However, in contrast to cyclophosphamide, RRRE caused no reduction in normal bone marrow cells. In animals given both RRRE and cyclophosphamide, the RRRE increased the antimetastatic effect of cyclophosphamide by 36 percent (p<0.05). RRRE also increased the number of leukocytes by 30 percent and myelokariocytes by 16-18 percent.

In another mouse tumor model, Udintsev and colleagues showed that RRRE (minimum 0.8 percent salidroside and 3 percent rosavin) increased the antitumor effect of the drug adriamycin while substantially reducing its liver toxicity.⁸⁹ Many chemotherapy agents are hematotoxic (reduce the number of normal blood cell precursors in bone marrow) or hepatotoxic (cause damage to the liver). These serious side effects were significantly ameliorated by RRRE. Thus, the research suggests that RRRE can both enhance tumor inhibition by chemotherapeutic drugs while alleviating dangerous side effects.

Is Rhodiola Rosea Antimutagenic?

Substances that reduce the incidence of chromosomal aberrations are termed antimutagenic. Salikhova and colleagues found that in mice injected with cyclophosphamide, RRRE (minimum 0.8 percent salidroside and 3 percent rosavin) had antimutagenic effects.⁹¹ Compared to placebo controls, RRRE reduced the development of chromosomal aberrations by 50 percent and reduced the incidence of cells with micronuclei by more than 50 percent. RRRE also increased indices of DNA repair in bone marrow cells after exposure to the mutagen N-nitroso-N-methylurea (NMU).⁹¹

Why We Need More Placebo-Controlled Studies of Rhodiola

In a small pilot study of 12 patients with superficial bladder carcinoma (TIG1-2), treatment with RRRE (minimum 0.8 percent salidroside and 3 percent rosavin) improved parameters of leukocyte integrines and T-cell immunity.⁹² The average frequency of relapse was reduced, but did not reach statistical significance. Larger placebo-controlled studies of R. rosea extracts to augment tumor inhibition and reduce toxic effects of chemotherapy agents are needed.

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Table of Contents: Rhodiola Rosea: A Phytomedicinal Overview
Credits and References

Supplemental Reading:

• Rhodiola Benefits
• Rhodiola Side Effects
• Rhodiola for Herbal Stress Relief
• Rhodiola Supplements for Muscle Development and Athletic Performance
• Rhodiola Rosea Pharmacology, Phytochemistry and Standardization