Background: Menopausal symptoms are a frequent problem for breast cancer survivors, resulting from several treatment options that can induce an estrogen deprivation state. Since hormone replacement therapy in these patients is not recommended and the efficacy of non-hormonal therapies is still unclear, the aim of this study was to evaluate the efficacy of a homeopathic treatment to relieve menopausal symptoms in patients with a history of non metastatic breast cancer.Study design: The study was carried out between 2005 and 2011 in a single centre and was conducted in two steps: a phase II pilot study, where ten patients received a homeopathic treatment for three months (phase A) followed by a phase III randomised study, where 35 patients received either homeopathic treatment or placebo for six months (phase B). Women with a history of breast cancer, without metastatic disease, suffering from menopausal symptoms were included in the study. A 5-point numerical scale was used to evaluate the severity of the menopausal symptoms. The sum of the scores (total score) at baseline and after 3 months (phase A) or 6 months (phase B) were compared.Results: In the pilot study (phase A) we observed a mean reduction in the total score of 2.27 (SD + /-0.59) and a statistically significant reduction of the severity of hot flashes (p = 0.01), vaginal dryness (p = 0.027) and headache (p = 0.015). In the placebo controlled study (phase B) we observed a statistically significant difference in favour of the homeopathic treatment for night sweats (p = 0.0097), gastric symptoms (p = 0.039) and for the total score (p = 0.018).Conclusions: According to the results, this homeopathic treatment showed a significant effect on some menopausal symptoms compared with placebo and can be considered as a safe and valid option for the treatment of menopausal symptoms in breast cancer survivors.