Magnesium oxide supplements for the treatment of post-chemotherapy sleep disturbance.

175 Background: While every cancer patient suffers from anxiety and sleep disturbance during cancer treatment, many physicians do not recognize that these problems can continue long after treatment has ended. Many cancer patients feel increased anxiety immediately after treatment ends when they find themselves “on their own,” without the protection of the medical armamentarium. The fear of recurrence, uncertainty about the future, a sense of vulnerability, awareness of mortality, and grief for the loss of a disease-free life all contribute to anxiety and sleep disturbance long term. Magnesium has been used for sleep induction and relaxation for centuries. The primary mechanism by which sleep is enhanced is by muscle relaxation. Magnesium induces muscle relaxation by preventing calcium from binding to troponin, parvalbumin, myosin, and calmodulin, thereby blocking muscle contraction. High levels of free magnesium competitively bind these proteins, and the slow dissociation of bound magnesium provides prolonged relaxation. It is for this reason that magnesium has a long history of use as a tocolytic in labor, as an adjunct to asthma treatment, and as a powerful laxative. Methods: 23 patients in a primary care practice reported continued anxiety and difficulty with sleep initiation following chemotherapy and/or radiation for various forms of cancer. Rather than use SSRIs, benzodiazepines, or sleep medications, all patients were started on an over the counter 1,000 mg magnesium oxide supplement, taken 1 hour before bedtime for 2 weeks. Results: Four patients dropped out before the end of the study period due to magnesium-induced diarrhea. 19 patients completed the 2-week study. Of these, 14 reported a noticeable reduction of sleep latency and an improvement in sleep quality. 11 also reported a subjective sense of reduced anxiety overall. 5 reported an improvement in nocturnal leg cramps, which had been interfering with sleep quality. Conclusions: Overall, magnesium proved to be a well-tolerated treatment for sleep disturbance and anxiety in the majority of the patients studied.