bottle of magnesium pills

Q. I have read that magnesium is an important supplement but I have no idea how much to take. Can one overdose on this element? Is it really as important as calcium?

A. Magnesium is crucial for virtually every cell in the body. This mineral rarely gets the respect it deserves. People are frequently advised to get extra calcium, though too much could be problematic.

Doctors also recognize that potassium is essential, especially for people on blood pressure or heart medicine containing potassium-depleting diuretics. They should monitor potassium levels regularly when patients are on drugs such as HCTZ or furosemide. But physicians don’t always plan to monitor of magnesium levels or recommend supplementation, although the same diuretics that affect potassium can also have an impact on magnesium.

Magnesium is absolutely essential for bone health and heart function. When magnesium levels drop too low, irregular heart rhythms may result. Other conditions that may be related to magnesium deficiency include anxiety and depression, pain, migraines, infertility, preeclampsia, kidney stones, reflux, asthma, constipation, hypertension, insomnia and Raynaud’s syndrome (painful extremities related to cold temperature and lack of adequate circulation).

So What Is the Right Magnesium Dose?

A safe magnesium dose ranges from 300 mg to 500 mg. Too much magnesium can lead to loose stools or diarrhea. People with kidney disease must be careful not to take too much magnesium as it may aggravate the condition.

Here are some stories from readers and visitors to this website about the benefits of magnesium:

“I often read about people having trouble getting a good night’s sleep. Perhaps my story will help someone.

“My pharmacist recently told me to take my magnesium tablets at bedtime instead of with breakfast. What a shocker to find such a difference in falling asleep. I no longer need to take melatonin or Tylenol PM.”

 “I have had a lot of trouble with constipation. I tried Metamucil, but it made things even worse. I tried Citrucel but I’m sensitive to citrus fruits, so I became more bloated.

“Finally a nutritionist suggested I take a magnesium dose of 800 mg daily. This balances my calcium intake.

“After the second day of the magnesium  supplements I became ‘like a normal person.’ It has also helped my fibromyalgia. I have read that people with fibromyalgia usually require a higher intake of magnesium. I am no doctor, but I know my own body and the magnesium has made a world of  difference.”

800 mg of magnesium may be too much for most people, especially those with reduced kidney function. If you discover you are having to run to the bathroom to avoid an accident, that would be a clear indication that you are getting too much of a magnesium dose!

 “I have gradually withdrawn from diazepam (Valium), flurazepam (Dalmane) and amitriptyline (Elavil). I had read that magnesium is a natural tranquilizer and have found that taking this mineral is very helpful for my nerves.”

 “Many people have horrible leg cramps and cannot take quinine because it has been taken off the market. I am 70 years old and have suffered with leg cramps all my life. Years ago, I used to take OTC quinine tablets, but quinine water (tonic) never worked for me.

“A long time ago I found that 250 mg tablets of magnesium at bedtime worked like a charm in warding off leg cramps and restless leg syndrome.”

If you would like to learn more about the miracle of magnesium for constipation, headaches and migraines, high blood pressure, insomnia, muscle and leg cramps, as well as restless leg syndrome, you may wish to consult our 264 page book, The People’s Pharmacy Quick & Handy Home Remedies. Here is a link to more information.

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  1. Jane

    I was taking 500 mg. of magnesium and was feeling well but horrible, horrible diarrhea. So I stopped. Any comments on transdermally applied magnesium oil since it bypasses digestive system?

  2. Jane
    St. Louis, MO

    I would NEVER do anything I read in your columns from other readers. It would be dangerous in my mind to take the advice of people who I don’t know and who aren’t professionals. Why don’t you give a decent answer to everyone who has the same problem rather than allow your People’s Pharmacy website be a place for anyone to suddenly become a doctor without a degree.

    Thank you.

    Jane from St. Louis, MO

    • Mary
      Charleston SC

      Jane – from long experience, I’m the opposite: I never take a doctor’s prescribed medicine without checking on how other people have reacted to it, and this habit has saved me quite a bit of grief. Unfortunately, doctors too often depend entirely on drug company propaganda for information on the drugs they prescribe. Drug companies have to keep their stockholders happy with high profits. Maybe it’s a choice between ignorance and greed, but I think the patients who write in at least are honest about how their own bodies react to drugs. Do you always trust the honesty of drug companies? Unfortunately I don’t.

  3. Tashi

    Mg glycinate (600mg) daily, vit d, Arjuna and Ashwaghandha have helped me with PVCs ( thousands each day). I got advi
    Ce from an ayurvedic practitioner that was also trained in Chinese and American herbalism.

  4. Millie

    I was diagnosed in 2002 with MS after having sought medical help for numbness in my right hand in 1994 and was told that I had suffered a small stroke.

    MRI in 2002 showed brain lesions consistent with MS. I have had numerous tests and see a neurologist at an MS clinic in a very reputable medical center. I have fatigue, leg muscle spasms, etc. along with problems walking.

    A few years ago I asked my primary care doctor to check my Vitamin D level. It was below 20, and now I take supplements to keep it in the normal range. A friend who was having some health problems mentioned that he had begun to take magnesium which seemed to really help him.

    I don’t know what his condition is, but it’s not MS. So I began taking 400mg at bedtime. It has helped my sleep. About a week ago I awoke and realized my right hand was not numb. Also, I have not taken any diazapam for leg spasms for several weeks.

    Could the magnesium be helping this much? I have just finished a 200 capsule size bottle. I take other medications which include omeprazole, lisinopril with Hctz, and simvastatin. I’m being cautiously optimistic, but when I read today’s stories about magnesium I just had to tell someone. I plan to share this with my neurologist on the next visit.

    I’m 79 years old and exercise three or four times a week at our recreation center. The major part of the exercise program is water aerobics (Ai Chi) in the therapy pool.

    • Terry Graedon

      The omeprazole could have depleted your body of magnesium. Good to hear it is helping.

  5. Patricia
    Atlanta, GA


    I have been taking 2 rounded teaspoons of magnesium, along with 2 Colon Care capsules for almost a year now. I sometimes only take one Colon Care capsule. The first thing I noticed was I slept longer at night. Still having Chemo induced Neuropathy. Mood has improved. Taking it at night works for me.

  6. Brian

    I have noticed that this article doesn’t address the various types of magnesium available OTC. Many people are unfamiliar with the fact that they need to obtain a magnesium supplement that has a high degree of bioavailability. Unfortunately, when choosing a Mg supplement, the majority of people are not aware that these supplements aren’t created equal. To the best of my knowledge, and please correct me if I am wrong, magnesium glycinate delivers the highest level of bioavailability. Mg citrate is somewhere in the “middle” (~40-60%), while magnesium oxide (a very common form found OTC), is the lowest in terms of bioavailability (~8%).

    If anyone is able to contribute to this post, your thoughts would be extremely helpful.

  7. Paul Hallett

    Wow, this mineral actually works! I take magnesium and calcium 4:1 (650mg:250mg) proportion along with Vitamin D (500IU) because I need more magnesium, vitamin D and less calcium when it comes to school and learning. I also take another magnesium tablet (500mg) during the evening time before I go to bed and my sleep has improved so much! I love this mineral to death! I say I am very happy that I’ve found this mineral and it works like a charm. :)

  8. Carol
    Ontario, Canada

    I am 50 yrs old. I have high blood pressure and suffer from panic attacks, my friend suggested I try Magnesium & Omega-3 and B-12. I’m going to start tomorrow . All the comments seem to say good things about these 3 pills. Hopefully, they will work for me as well.l

  9. Mary
    San Jose, CA

    How much magnesium is safe for a 2 year old with chronic constipation?

    • Dylan
      Minneapolis, MN

      Do you really think you should give a two year old a dose of ANYTHING on the advice of some anonymous person on an internet comments section? I don’t mean to be rude but that just seems dangerously reckless. This is a question for a doctor or a pharmacist.

    • Dylan
      Minneapolis, MN

      I just noticed that the website itself has someone responding to questions on here. That makes it a little less bad, I guess. I still feel like you should be asking someone that you’re positive is a qualified professional though.

    • Kelly


      • Mary

        The grandchild of someone I know was recently taken to the hospital after he collapsed. Cause was unknown and they were scared.
        It turns out the child was dehydrated.

        Keep hydration up AS WELL as taking any magnesium

  10. sherry
    United States

    Has anyone had symptoms of swelling or edema in legs after starting a magnesium supplement?

  11. robert a.
    United Kingdom

    I’m glad I heard about magnesium not via my dr though, as I shake big time without it I cant make out how much I’m taking… I think it’s about 500 mg per day but recently its starting to get quite bad again but very reluctant to go to drs as I know they will just put me on more tabs I don’t really want to take as I take enough tabs already.

  12. chris
    Melb Australia

    I take 150mg of magnesium daily as well as 1000mg deep sea krill oil & 3 macafem tablets daily. ( i have doing this for about 1 month) While I was taking these immediately after breakfast – I was feeling fine. In the last 2 weeks I started to take these after my evening meal. Since then I have started to feel bloated and nauseous after meals & sometimes break out in a sweat. Why? Do these tablets have negative affects on each other? Should I be taking them for prolonged periods of time? Please note I am post menopausal & had libido problems before adding Macafem to the other 2 supplements (above) that I was taking.

    • The People's Pharmacy

      Chris, we are not aware of interactions between them. However, if you don’t feel good after taking them, you might go back to your original schedule or take them at different times from each other.

  13. jude newman
    brisbane queensland

    To learn all you need to know about magnesium go to . I take 300mgs morning and night.

  14. cerwin

    I see this post is several years old. However, I felt this person’s pain and need for help. I suffer from the same symptoms and elephant leg swelling. I also take the water pills hydrchlorothizide. MY Dr. Has yet to help this ongoing problem along with others like the irregular heartbeat. I was very curious if you have found relief or help? And if magnesium has helped? How much if so?

  15. Pat

    I started to use Magnesium Oxide 500 mg. in hopes it would help with constipation especially taken every day… no luck so far.
    Perhaps S.Jones could help me with this as I noticed they had written that the 500 mg. helped with their constipation problem.
    Any advice is greatly appreciated.

    • Diana

      Magnesium OXIDE is the worst form of magnesium that you can buy. It is not easily absorbed by the body so it’s almost useless. Purchase Magnesium Glycinate, Chelated Magnesium, or Elemental Chelated Magnesium. Magnesium Citrate is good too, it’s just more likely to cause loose stools (which could be a good thing if you find you’re often constipated).

    • higgij310
      Schenectady, NY

      Magnisium Oxide is not a form absorbed well. You may only be absorbing 4%. Try chelated type.

    • Emmylou

      You may want to try Miralax. for constipation.You can purchase the generic version at Walgreens. It is less expensive. Every person reacts differently to certain products, vitamins, as well as medicines. I have had a very good experience with the generic version of Miralax. It combines very well with coffee, tea, or juices. You won’t even know it has been mixed in. I hope this works for you.

  16. enia

    I’ve been suffering with horrible PVC’s for about three years now. beta blockers doesn’t seem to help much, so I’m trying other things. Question for all of you who have experience with magnesium and PVC’s: what kind of magnesium do you think is the best and how much to take daily? I’ve read that magnesium glyconate is well absorbed and easier on the stomach than citrate and oxide… Thank you all, I’m desperate to feel better, these skipped beats are literally driving me crazy every day :(

    • Candis

      I also suffer from PVC’S and someone told me to try magnesium. I am taking the magnesium oxide 250mg and have been taking for 2 weeks now. I felt 100% better the first day taking them. I was having 50 extra heart beats daily and now it feels like 2 or 3 daily so a huge change for me. I was also having a ton of anxiety and panic attacks everytime I would think my heart was going to stop or think I was having a heart attack. Well, I am a witness that I have been so calm and haven’t had any attacks since taking them. Not even any anxious feelings either. I take one before bed. When I took one in the mornings, I was too sleepy to work so I started taking it before bed. Working wonders for me.

    • Stephanie

      This comment is for everyone. Supplements in general are of great benefit, but you have to look at what you are eating and drinking. Carbonated beverages and things like Gatorade can cause mineral imbalances in our bodies. Look up what minerals/vitamins are in specific fruits and veggies, and start eating more of them. It is amazing that you can fix a lot of problems with digestive enzymes and organic foods, along with supplements.

  17. S. jones

    I was always having problems with constipation no matter how much water I drank every day.. i was told “oh drink more water” …so I did and I was STILL constipated…I heard/read that magnesium works wonders with constipation and I thought what do I have to lose.
    I started taking 500mg every evening with my meal and come morning, lets say, I no longer have that problem. I also always had lots of headaches… taking magnesium has helped that as well along with heart palpitations… magnesium is all I take and it seems like it has helped me immensely with everything…
    My husband has high blood pressure and no matter what “pill” the doctors gave him it isn’t working… his blood pressure is still high… after ready some of these posts I am strongly going to suggest he maybe try magnesium to help get it under control…

  18. Judy

    how much do you take to be effective?

  19. TL

    I recently found out I have rapid a rapid heart beat and it scared the *#$%@! Out of me I have always been active and happy. But for 6 to 8 months I have been laid off and depressed over some life issues. I have read some of the comments. And it sounds like magnesium is what I need to start to get things pointed in the right direction.
    Can some please plan and clearly suggest what type pill or powder the name on the bottle and how much to take to start of 250 300 400mg…. I’m real cautious because I never really got sick and now I have this… I do eat anything I want I smoke and now that I stopped smoking and am on a diet I just was wondering if someone could suggest for me what kind and how much to take …I am 31 yr. Old

  20. EMS

    I would call magnesium supplements the miracle I was looking for, having open heart surgery triple bypass at 40 yrs of age, I needed all the help I could get. I am a 13 yrs survivor, my heart is healthier now because of magnesium, no palpitations, no irregular heart beat, great blood pressure, I guess I’ve said enough it truly has been my miracle mineral… you have nothing to lose but a whole lot to gain, trust me… it also helps my mood in a huge way…. making stress easier to handle in my daily life.

  21. dlr

    yes I take that for the irr. heart beat and also trying for restless legs that drive me insane especially in the summer heat at nite.

  22. T.J.

    I was on blood pressure meds for 8mos now I’m having heart problems SVT never had heart problems until I started taking blood pressure meds, The doctor put me on a 24hr holter monitor the monitor showed my heart was pausing now I have a pacemaker inside me, but I still have pvc’s & rapid heart beats so I started taking magnesium & I don’t have the pvc’s & rapid heart beats any more….

  23. catherine

    having used the epsom salt in a bath never realized the dose or how it helped me, I only used it for pain, until a few weeks not using it my anxiety was back and awful. I never measured it just poured it in. Well went I went back on it i felt better, stopped using it then I was very sick for about 2 months and well from problems with low heart rate, bad panic attacks and such.
    I ran off to the doctors for test nothing was found. My other doctor thought it was withdrawal from caffeine and nicotine but I had been drinking caffeine and still using cigarettes. I even thought it was pre menopause but gyno said he did not think so. I had episodes of uncontrollable shaking one day lasting 3 hours and other days small amount of time 20 minutes a hour. My blood pressure also through the roof heart rate was low.
    I almost had to go to the hospital, it scared me to death, still had the shakes for days till I recalled in my head I have not bathed with epsom salt in a long time. I used only a little bit I scared myself reading the label high magnesium at least 435 mg in a teaspoon here a few months ago I put in a cup full. So I used a little bit and the shakes were less, is this a problem did my doctor test this probably not, I sit and wonder.
    There is a reason and solution, to my problem epsom salt may be helping will consult doctors soon. I do not want to over do it or cause myself harm. I post this because maybe someone else has this problem too. Maybe this can help you, The comments seem to help me know that i am not crazy,

  24. Lynn

    I have been told that magnesium and vitamin d taken in the proper quantity can do wonders for a person’s well being. What I would like to know is are there any supplements available that can be taken daily and what would the dosage be. Any feedback would be appreciated, thank you.
    PEOPLE’S PHARMACY RESPONSE: We think that wintertime vitamin D supplementation should range between 1,000 and 4,000 IU daily, which could be guided by a test your doctor could conduct of 25-hydroxy-vitamin D. That should be at least 30 ng/ml.
    Magnesium supplementation between 200 and 500 mg/day should be safe except for those with impaired kidney function. (They should avoid magnesium supplements altogether.) Diarrhea is a signal that the dose of magnesium is too high. The dose can be adjusted downward.

  25. Mike

    I have been on Xanax for years for anxiety. I started taking magnesium & it is actually better. I found that all magnesium hurts my stomach except for Chelated Magnesium. I get it at the national chain store…Vitamin Shoppe. Solgar & Country Pride both make Chelated magnesium. Both are good, country pride is cheaper. I found magnesium to help my whole body & mind

  26. Janet

    Try taking Omega 3 and see if it helps with depression. Just take less magnesium and add Omega 3.

  27. Robert

    I am 63, have bi-polar type 2 with PTSD, take Effexor XR 150mg. Lately I tried adding magnesium to my meds and noticed an increase in my depression. This increase ended when I stopped the magnesium. I waited and then tried the magnesium again with the same increase in depression. Has anyone had this happen? I have read all the articles stating that magnesium has helped many depressives, and I can’t find anything about magnesium increasing a person’s depression.

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