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Mineral supplement

Calcium: uses, side effects & precautions

Also known as Calcium carbonate, Calcium citrate, Calcium supplement, Caltrate, Adcal.

Deze informatie is uitsluitend bedoeld als algemene richtlijn en vormt geen medisch advies. Raadpleeg altijd een gekwalificeerde zorgprofessional voor persoonlijke medische vragen. Bel in geval van nood uw lokale alarmnummer.

What it is used for

  • Preventing and treating low calcium levels
  • Supporting bone health, often alongside vitamin D, in people at risk of weak bones
  • Helping prevent and manage osteoporosis as part of a clinician's plan
  • Some forms also used as an antacid for indigestion

How it works

Calcium is the main mineral in bones and teeth and is also needed for muscle movement, nerve signals and blood clotting. Supplementing helps keep blood calcium steady and supports bone strength when dietary intake is not enough.

How it is taken

Available as tablets, chewable tablets, effervescent tablets and liquid, sometimes combined with vitamin D. Calcium carbonate is best taken with food, while calcium citrate can be taken with or without food. Take it exactly as your doctor, pharmacist or the label directs, and avoid taking very large amounts at once.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Constipation
  • Bloating or wind
  • Stomach upset

Serious effects — get help

  • Signs of very high calcium: nausea, vomiting, confusion, weakness, excessive thirst or urination
  • Kidney stones with long-term high intake
  • Irregular heartbeat in severe cases

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Iron, zinc and some thyroid medicines, which should be spaced apart from calcium
  • Certain antibiotics (tetracyclines, quinolones)
  • Some blood pressure and heart medicines
  • Other supplements or antacids that also contain calcium

Who should take care

  • Tell your clinician if you have kidney disease, kidney stones or high calcium levels
  • Take vitamin D as advised, since it helps calcium absorption
  • Do not greatly exceed the recommended amount, as more is not better for bones
  • Spread doses through the day rather than taking a large amount at once if advised

Frequently asked questions

Do I need calcium tablets if I drink milk and eat dairy?
Many people get enough calcium from a balanced diet. Supplements are mainly for those who cannot meet their needs through food or have specific medical reasons. Ask your clinician if you are unsure.
Should I take calcium with vitamin D?
Vitamin D helps your body absorb calcium, so the two are often taken together, especially for bone health. Many products combine them.
Why does calcium make me constipated?
Constipation is a common effect, particularly with calcium carbonate. Drinking enough water, eating fibre, or trying calcium citrate may help. Ask your pharmacist.
Can taking calcium cause kidney stones?
Very high intake, especially from supplements, may increase the risk in some people. Stick to recommended amounts and tell your clinician if you have had stones.
Is Calcium safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

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