Potassium supports the normal function of your cells, tissues and organs. Your heart, muscles and kidneys require magnesium to perform at their best and calcium helps maintain strong bones and teeth. You can get these minerals from your diet, but in some cases, you may need to take a supplement. Consult your doctor before considering supplements, because they can interact with certain medications and cause side effects.
You should take 4,700 milligrams of potassium every day. Potassium, which comes in regular tablets, powder, granules and oral liquid, is taken two to four times daily with or after meals, states MedlinePlus. Add the liquid forms of the supplement to water. Mix the powder, granules or effervescent tablets with cold water or fruit juice, according to the instructions on your prescription label. Do not chew extended-release tablets and capsules or dissolve them in your mouth; instead, swallow them whole.
Magnesium by injection requires a prescription from your doctor. The UMMC suggests that you take a B-vitamin complex or a multivitamin that contains B vitamins because vitamin B-6 levels in your body determine how much magnesium can be absorbed into your cells. Men age 19 to 30 need 400 milligrams of magnesium per day. Women in the same age group should aim to get 310 milligrams a day. Men and women 31 and over require 420 milligrams and 320 milligrams of magnesium daily, respectively.
Take calcium supplements in small amounts -- no more than 500 milligrams a day -- in divided doses with six to eight cups of water, advises the UMMC. This will help prevent side effects such as gas, constipation and bloating and also enhance the absorption of calcium. Men and women between ages 19 to 50 should aim to get 1,000 milligrams of calcium daily. This amount remains the same for men age 51 to 70. Women who are 51 and older need 1,200 milligrams per day. Over age 70, men need 1,200 milligrams of calcium each day. Vitamin D helps your body absorb calcium; therefore, choose calcium supplements that supply vitamin D.
Consult your doctor before taking supplements. Going overboard with potassium supplements can cause side effects such as stomach irritation, nausea and diarrhea. You may also experience abnormal heart rhythm, muscle fatigue and slowed heart rate. Potassium supplements can react with certain medications such as nonsteroidal, anti-inflammatory drugs, angiotensin receptor blockers, ACE inhibitors, indomethacin and thiazide diuretics. Excessive magnesium supplement use can cause a low heart rate, nausea, vomiting, cardiac arrest and deficiencies of other minerals. Magnesium supplements can interfere with some medications such as diabetes medications, blood pressure medications, diuretics and antibiotics. Getting too much calcium can cause stomach upset, constipation, increased urination, kidney damage and nausea. Calcium supplements can react with a variety of medications, including anti-seizure medications, corticosteroids, cholesterol-lowering medications, digoxin and antibiotics.