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 told to get extra calcium, though too much could be problematic.

There is also recognition that potassium is essential, especially for people on blood pressure or heart medicine containing potassium-depleting diuretics. But there are rarely calls for careful monitoring of magnesium levels or recommendations for supplementation.

Magnesium is absolutely essential for bone health and heart function. When magnesium levels drop too low (also a complication of diuretic use), 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).

A safe dose of magnesium 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 800 mg of magnesium 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 too much magnesium is on board!

 “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. 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.

  2. 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.

  3. jude newman
    brisbane queensland

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

  4. 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?

  5. 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).

  6. 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 :(

  7. 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…

  8. Judy

    how much do you take to be effective?

  9. 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

  10. 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.

  11. 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.

  12. 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….

  13. 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,

  14. 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.

  15. 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

  16. Janet

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

  17. 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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