What is it?
Calcium is a mineral used to treat osteoporosis (bone loss), kidney stones, and menstrual cramps. It is also used as a vitamin supplement to increase bone mass and is used as an antacid (to treat stomach acid upset).
Other names for calcium include: calcium acetate, calcium carbonate, calcium chloride, calcium citrate, calcium gluceptate, calcium gluconate, calcium oxide, calcium salt, and oyster shell calcium.
Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.
Tell your doctor if you
- are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
- are pregnant or plan to become pregnant while using this medicine
- are breastfeeding
- have any other health problems, such as high blood pressure or heart or blood vessel disease
Talk with your caregiver about how much calcium you should take. The amount depends on the strength of the medicine and the reason you are taking calcium. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.
To store this medicine:
Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.
Drug and Food Interactions:
Do not take calcium without talking to your doctor first if you are taking:
- Medicines used for osteoporosis (examples: alendronate (Fosamax(R)), etidronate (Didronel(R)), ibandronate (Boniva(R)), risedronate (Actonel(R))) (2,30,35)
- Guar gum (52)
- Heart or blood pressure medications (examples: atenolol (Tenormin(R)), captopril (Capoten(R)), digoxin (Lanoxin(R)), propranolol (Inderal(R)), verapamil (Calan(R), Isoptin(R))) (8,25,26,38)
- Water pills (examples: chlorothiazide (examples: Diurigen(R), Diuril(R)), chlorthalidone (Hygroton(R), Thalitone(R)), hydrochlorothiazide (Esidrix(R), Hydro-Par(R), Microzide(R)), indapamide (Lozol(R)), methyclothiazide (Aquatensen(R), Enduron(R)), metolazone (Mykrox(R), Zaroxolyn(R))) (3,4)
- Medicines used to treat bacterial infections (examples: cefpodoxime (Vantin(R)), cefditoren (Spectracef(R)), ceftriaxone (Rocephin), ciprofloxacin (Cipro(R)), levofloxacin (Levaquin(R)), ofloxacin (Floxin(R)), doxycycline, tetracycline) (12-14,29,34,54)
- Medicines to treat fungal infections (examples: itraconazole (Sporanox(R)), ketoconazole (Nizoral(R))) (16,27,28)
- Medicines to treat human immunodeficiency virus infection (HIV) (examples: amprenavir (Agenerase(R)), fosamprenavir (Lexiva), tipranavir (Aptivus(R))) (31,32,33)
- Medicine used to treat certain stomach and intestinal tract problems (example: hyoscyamine (Cystospaz(R), Levsin(R))) (36)
- Medicine used to treat symptoms of acid reflux disease such as heartburn or ulcer (examples: lansoprazole (Prevacid(R)), sucralfate (Carafate(R))) (37,42)
- Medicine used to treat hyperkalemia (high levels of potassium in the blood) (examples:sodium polystyrene sulfonate Kayexalate(R), Kionex(R), Marlexate(R)) (39,40,41)
- Medicine used to help prevent strokes by keeping blood clots from forming in the blood vessels (example: ticlopidine (Ticlid(R))) (43)
- Medicine used to treat a bone disorder called Paget's disease (example: tiludronate (Skelid(R))) (44)
- Medicine used as a blood thinner, or to treat pain or fever (example: aspirin (Alka-Seltzer(R), Anacin(R), Aspergum(R), Bayer(R), Bufferin(R), Ecotrin(R), Zorprin(R))) (45-48)
- Medicine used as a laxative (example: bisacodyl (Dulcolax(R))) (49)
- Thyroid medicine (examples: Armor Thyroid(R), Synthroid(R), levothyroxine(R)) (5)
- Dietary supplements (iron and zinc) (50, 51)
- Dairy foods, bran, whole cereals, spinach, or rhubarb (A light meal is recommended when you take calcium; however, these should be avoided) (4, 24)
- Medicine used to treat cancer (example: erlotinib (Tarceva(R))) (55)
- Medicine used to treat low blood platelet counts (example: eltrombopag (Promacta(R)) (56)
- Before taking calcium, tell your doctor if you are pregnant or breastfeeding
- Tell your doctor if you have kidney disease or kidney stones (too much calcium may cause kidney stones) (7)
- Make sure your doctor knows if you have an allergy to shellfish (53)
- You should not use certain brands of this medicine if you have kidney disease or are on dialysis. Some brands contain ingredients that could be harmful if your kidneys are not working properly. Always ask your health caregiver what specific brands of this medicine will work best for you (53).
- Some health problems can affect how much calcium you should take. Tell your doctor if you have stomach or digestion problems, such as on-going diarrhea, not absorbing nutrients properly, or not having enough acid in your stomach (53).
- If you are using a large amount of calcium or using it for a long time, your doctor might need to check your blood on a regular basis. Be sure to keep all appointments (53).
Call your doctor right away if you have any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hand, swelling or tingling in your mouth or throat, chest tightness, trouble breathing, or rash
Other Side Effects:
You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.
- Headache that will not go away, dry mouth, loss of appetite (53)
- Severe constipation (not able to have a bowel movement) (4, 53)
- Stomach pain, vomiting (can occur if you take too much calcium) (7)
- Stomach upset (more likely to be caused by calcium chloride and calcium gluconate; if stomach problems occur, try calcium lactate (after checking with your doctor or pharmacist) as this may lessen it) (4)
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12. Product Information: Vantin(R), cefpodoxime. Pharmacia & Upjohn Company, Kalamazoo, MI, (PI revised 11/2000) reviewed 3/2002.
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17. Product Information: Levsin(R), hyoscyamine sulfate. Schwarz Pharma, Inc., Milwaukee, WI, 1996.
18. Product Information: Pamine(R), methscopolamine. Upjohn Company, Kalamazoo, MI, 1991.
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20. Product Information: Tritec(R), ranitidine bismuth citrate. Glaxo Wellcome Inc., Research Triangle Park, NC, 1999.
21. Product Information: Carafate(R), sucralfate. Hoechst Marion Roussel, Inc., Kansas City, MO, 1996.
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30. Product Information: Actonel(TM), risedronate. Procter & Gamble Pharmaceuticals, Inc., Cincinnati, OH, 1998.
31. Product Information: Agenerase®, amprenavir. Glaxo Wellcome Inc., Research Triangle Park, NC, 2000.
32. Product Information: Lexiva(TM), fosamprenavir. GlaxoSmithKline, Research Triangle Park, NC, 2003.
33. Baldwin JR, Borin MT, Wang Y, et alBaldwin JR, Borin MT, Wang Y, et al: Effects of food and antacid on bioavailability of the protease inhibitor PNU-140690 in healthy volunteers (abstract), 5th Conf Retrovir Oppor Inf, Chicago, 1998.
34. Product Information: Spectracef(TM), cefditoren pivoxil. TAP Pharmaceuticals, Inc., Lake Forest, Illinois, 2001.
35. Product Information: Boniva(TM), ibandronate sodium tablets. GlaxoSmithKline, Research Triangle Park, NC, 2003.
36. Product Information: Levsin(R), hyoscyamine sulfate. Schwarz Pharma, Inc., Milwaukee, WI, 1996.
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41. Schroeder ET: Alkalosis resulting from combined administration of a "non-systemic" antacid and a cation-exchange resin. Gastroenterology 1969; 56:868.
42. Product Information: Carafate(R), sucralfate. Hoechst Marion Roussel, Inc., Kansas City, MO, 1996.
43. Shah J, Fratis A, Ellis D, et al: Effect of food and antacid on absorption of orally administered ticlopidine hydrochloride. J Clin Pharmacol 1990; 30:733-736.
44. Product Information: Skelid(R), tiludronate. Sanofi Pharmaceuticals, Inc., New York, NY, 1998.
45. Feldman S & Carlstedt BC: Effects of antacid on absorption of enteric-coated aspirin. JAMA 1974; 227:660.
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49. Product Information: Dulcolax(R), bisacodyl. Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT, 1993.
50. O'Neil-Cutting MA & Crosby WH: The effect of antacids on the absorption of simultaneously ingested iron. JAMA 1986; 255:1468-1470.
51. Wood RJ & Zheng JJ: High dietary calcium intakes reduce zinc absorption and balance in humans. Am J Clin Nutr 1997; 65(6):1803-1809.
52. Gulliford MC, Pover GG, Bicknell EJ, et al: Guar delays intestinal calcium absorption in man. Eur J Clin Nutr 1988; 42(5):451-454.
53. Product Information: Os-Cal(R), calcium carbonate. GlaxoSmithKline, 2004.
54. Product Information: Rocephin(R) injection, ceftriaxone sodium injection. Roche Pharmaceuticals, Nutley, NJ, 2008.
55. Product Information: TARCEVA(R) oral tablets, erlotinib oral tablets. OSI Pharmaceuticals Inc, Melville, NY, 2008.
56. Product Information: PROMACTA(R) oral tablets, eltrombopag oral tablets. Glaxo Smith Kline, Research Triangle Park, NC, 2008.
Last Updated: 3/4/2018