From the Guidelines
Melatonin as a supplement has no significant role in managing fatigue, anxiety, or depression in cancer survivors.
Evidence Summary
- The use of melatonin for fatigue management in cancer survivors has been studied in a small phase II crossover RCT, which found no significant differences in fatigue between patients receiving 20 mg of melatonin daily and those receiving a placebo 1.
- For anxiety and depression, multiple small RCTs have been conducted, but the results are inconsistent and often limited by small sample sizes and low overall risk of bias 1.
- One trial found a significant reduction in depression in women with breast cancer receiving melatonin perioperatively, but this trial had a disproportionate number of dropouts in the melatonin group 1.
- Other trials have found no impact of melatonin on anxiety or depression in patients with colorectal cancer, lung cancer, or advanced cancer 1.
- The majority of these trials were not designed to assess anxiety or depression as primary outcomes, and the sample sizes were often small, which limits the generalizability of the results.
- Overall, the current evidence does not support the use of melatonin as a supplement for managing fatigue, anxiety, or depression in cancer survivors.
From the Research
Role of Melatonin as a Supplement for Cancer Survivors
- Melatonin has been found to possess potent antioxidant, antiproliferative, immune-modulating, and hormone-modulating properties, which may have a possible role in the treatment of cancer 2.
- Clinical evidence suggests that melatonin may benefit cancer patients who are also receiving chemotherapy, radiotherapy, supportive therapy, or palliative therapy by improving survival and ameliorating the side effects of chemotherapy 2, 3, 4.
- Melatonin has been shown to inhibit cancer development and growth at various stages, including initiation, progression, and metastasis, and may render cancers previously resistant to treatment sensitive to conventional therapies 3, 5.
- The mechanisms of melatonin's anticancer effects include apoptosis induction, cell proliferation inhibition, reduction in tumor growth and metastases, and reduction in the side effects associated with chemotherapy and radiotherapy 4, 5, 6.
- Melatonin may be used as an adjuvant drug to conventional therapies, and its use has been found to improve the therapeutic effects of these therapies while reducing their side effects 2, 4, 5.
Potential Benefits of Melatonin for Cancer Survivors
- Improved survival rates and reduced mortality 2
- Amelioration of chemotherapy-associated toxicities, such as asthenia, leucopenia, nausea and vomiting, hypotension, and thrombocytopenia 2
- Inhibition of cancer growth and metastasis 3, 5, 6
- Reduction in the side effects associated with chemotherapy and radiotherapy 4, 5
- Enhancement of the therapeutic effects of conventional anticancer therapies 3, 4, 5