PEP Topic 
Hot Flashes

Magnesium is a mineral found in the body that helps to maintain proper muscle and nerve function. Approximately 50% of the body's magnesium is stored in bone with the rest stored in body tissues or blood. The body maintains a steady state of about 1% magnesium in blood. There are approximately 25g of magnesium in the body, and the mineral is responsible for more than 300 chemical reactions. Magnesium is found in green leafy vegetables, legumes, nuts, seeds, and whole grains.

Effectiveness Not Established

Research Evidence Summaries

Park, H., Parker, G. L., Boardman, C. H., Morris, M. M., & Smith, T. J. (2011). A pilot phase II trial of magnesium supplements to reduce menopausal hot flashes in breast cancer patients. Supportive Care in Cancer, 19(6), 859-863.


Study Purpose:

The study tested whether magnesium would diminish bothersome hot flashes in breast cancer patients

Intervention Characteristics/Basic Study Process:

Patients were assessed at baseline for all variables. They recieved magnesium 400 mg daily for 2 weeks. If symptom relief on hot flashes was seen, they stayed with same dose for 2 weeks more. If not, they increased  to 400 mg twice daily for 2 weeks.

Sample Characteristics:

Twenty-nine women with a mean age of 53.5 years were enrolled.  All were breast cancer patients with ECOG Performance status 0-1 & 2.  Patients were excluded if they:

  • Had decreased renal function or hypersensitivity to magnesium 
  • Were pregnant or nursing
  • Were receiving antineoplastic chemotherapy or other investigational drugs within 4 weeks prior to study 
  • Had an addition or change of androgens, estrogens, progestins, gabapentin, or antidepressants within 4 weeks prior to study entry; or any change in dose of tamoxifen, raloxifene, or aromatase inhibitors within 4 weeks.



Excluded Renal 


  • SITE: Single site   
  • SETTING TYPE: Not specified   
  • LOCATION:  Massey Cancer Center - Virginia, USA

Phase of Care and Clinical Applications:

  • PHASE OF CARE: Transition phase after initial treatment
  • APPLICATIONS: Late effects & survivorship; End of life and palliative care

Study Design:

This was an observational study.

Measurement Instruments/Methods:

Instruments and assessments included.

  • The Symptom Assessment Scale for overall quality of life
  • Linear analog scale Quality of Life questionaires
  • CTEP toxicities scale to asses toxicity
  • Hot flashes diary- 5 weeks
  • Self Assessment Scale  (21 questions) Dr Charles Loprinzi
  • ECOG Performance Status


Hot flash frequency and score were reduced with magnesium.  The average weekly hot flash score decreased by 50.4% from 109.8 (SE, 40.9) to 47.8 (SE, 13.8), p value 0.02. Magnesium does not have effect on overall quality of life. Fatigue and distress due to hot flashes showed modest benefit. Minor side-effects included migraine, headache, and nausea.                          


The findings suggest that oral magnesium supplementation is effective in reducing the severity and frequency of hot flashes in women after treatment for breast cancer


This study used a small sample <30. The study design was not controlled or randomized. There was possible variance in grading side-effects or toxicity. Magnesium should be tested in a larger population


Nursing Implications:

Magnesium may safely decrease hot flashes, with few side effects and low cost.  Further research in use of magnesium supplements is warranted.