Buy Calcium Online (Calcium Carbonate)
What is Calcium?
What is Calcium?
Calcium carbonate is an antacid used for heartburn, upset stomach, or acid indigestion, as a phosphate binder for chronic kidney disease, and as a dietary supplement for conditions such as osteoporosis. Forms of calcium carbonate include tablets, chewable tablets, and calcium carbonate powder for dissolving into water or use as a food additive. Use of calcium carbonate should be limited to two weeks if used as an over-the-counter medication. It is intended for adults and children over the age of 6.
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Purchase Calcium from Universal Drugstore today and save!
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Calcium Carbonate (generic Calcium)
Calcium Carbonate 500mg
Product of Canada
Marketed as Jamp-Cal in Canada.
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Important information about Calcium
Calcium carbonate (CaCO3) is a calcium salt that works differently depending on why you’re using it. As an antacid, it works by neutralizing the acid, releasing carbonic acid, which dissolves into carbon dioxide and water in your stomach to reduce the symptoms of acid reflux. It also helps promote gastric emptying, helping to reduce the symptoms of acid reflux. In certain conditions, like chronic kidney disease, it is sometimes used to help reduce high levels of phosphate (hyperphosphatemia) in your blood, acting as a phosphate binder. For conditions such as osteoporosis, it works by providing a source of calcium to help promote bone growth. Natural sources of calcium carbonate include eggshells, oyster shells, and dark leafy greens.
Follow all directions given to you by your doctor and read all documents provided, including the full Prescribing Information, FDA-Approved Product Labeling, Instructions for Use, and Medication Guide, before using Calcium. However, the following is a synopsis of the general guidelines for the use of Calcium:
- For heartburn, it should be taken when symptoms arise, or within one hour of a meal.
- To reduce phosphate levels, it should be taken at each meal with the first bite of food.
- If you are using a calcium carbonate suspension, ensure to shake well before use.
- Take your calcium carbonate with a full glass of water, and make sure to stay well hydrated while taking this medication.
The National Institute of Health recommends the following regarding dosing of calcium carbonate:
- For heartburn in adults, dosing should not exceed 7 grams daily.
- For calcium supplementation, 500 mg to 4 grams of calcium carbonate may be taken.
- For adults with hyperphosphatemia, 1.5 to 3 grams is usually effective.
The most common side effects of calcium carbonate seen in clinical trials as compared to placebo include:
- Constipation.
- Abdominal pain.
- Reduced appetite.
Some individuals may experience serious side effects while using calcium carbonate. These side effects may require immediate medical attention. If you experience any of the following, contact your healthcare provider or seek emergency medical help:
- Signs of high levels of calcium (hypercalcemia): fatigue, muscle weakness, loss of appetite, nausea/vomiting, constipation, bone pain, depression, confusion.
- Milk-alkali syndrome (a more severe form of hypercalcemia): Nausea, vomiting, anorexia, distaste for milk, headache, dizziness, vertigo, apathy, and confusion.
- Low phosphate levels (hypophosphatemia), which presents similarly to hypercalcemia.
- Kidney calcification (leading to kidney stones), presenting with severe lower back pain, blood in the urine, vomiting, fever, and chills.
- Acid rebound (if used for a long time).
These are not all of the possible side effects of calcium carbonate. You should always seek medical advice from your healthcare provider for any questions or concerns about your medical condition or treatment. Read all patient information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the Food and Drug Administration at www.fda.gov/medwatch or 1-800-FDA-1088.
Before starting calcium carbonate, it is crucial to discuss any existing health conditions with your healthcare provider. You should be sure that your healthcare provider is aware of all your medical conditions, including if you:
- Take medications that may increase your calcium levels: lithium, thiazide diuretics such as hydrochlorothiazide, teriparatide (Forteo), theophylline, other calcium products, and vitamin D.
- Have any of the following conditions: kidney disease, heart failure, or hypoparathyroidism.
Allergy or hypersensitivity to calcium carbonate or any filler ingredients in the formulation, kidney stones, high calcium levels in the blood or urine, low phosphate levels, Inability to produce acid in the stomach (achlorhydria), or suspected digoxin toxicity.
For heartburn, it works within minutes. For hyperphosphatemia, its effect may take a few weeks.
When calcium supplements are taken with other prescription drugs, over-the-counter medications, vitamins, and supplements, they may change how medications work or increase the frequency or severity of side effects. Make sure that you tell your healthcare professional about anything that you are taking to avoid any negative drug interactions, including:
- Bisphosphonates (alendronate), antibiotics (ciprofloxacin), thyroid medications (levothyroxine), and iron supplements. From a pharmacology standpoint, calcium carbonate may reduce the absorption of these medications. Make sure you take these an hour before or two hours after the calcium carbonate.
- Medications for heartburn/ GERD, such as pantoprazole or famotidine (Pepcid) - may decrease the absorption or bioavailability of calcium. When used together, calcium should be taken an hour before or two hours after any of these medications.
The amount of calcium varies between products. As a liquid, it is supplied as a 1250mL/5mL suspension. As a chewable tablet, it is supplied as 500mg or 750mg. For regular tablets, it is available as 500mg, 600mg, or 648mg tablets.
It should be kept at room temperature away from the reach of children or pets.
It is manufactured by many brands such as Tums, Maalox, and Rolaids.
Yes, it is available from most manufacturers of supplements.
For heartburn, it is used as needed and can be stopped when it is no longer needed. For hyperphosphatemia, it should be used under the direction of a physician and not stopped suddenly.
Calcium carbonate is considered safe in pregnancy. However, the recommended dietary intake is lower for pregnant females. Talk to your doctor if you are already pregnant or if you have any plans to become pregnant. They will know or recommend what is best for you.
Calcium carbonate is considered safe during lactation. Talk to your doctor if you are already breastfeeding or if you have any plans to breastfeed. They will know or recommend what is best for you.
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Once you complete your order, we process, verify, and dispatch your medication. You’ll receive email updates at each stage, including tracking details once your order ships. If any additional documentation is needed (such as a valid prescription), we’ll contact you promptly. Once approved, your order is charged and delivered directly to your doorstep.
Orders are typically processed within 1–3 business days once all required documents are received and approved. Standard delivery times range from 10–18 business days, depending on your location.
Yes! Once your medication ships, you will receive an email with tracking information so you can monitor your shipment every step of the way.
Our Customer Care team is available 24/7 to assist with any order-related concerns or questions. If you experience delays, missing items, or need support, contact us using the details provided in your confirmation email.
All orders are shipped in discreet, plain packaging to protect your privacy. Medications are securely packaged to prevent damage and ensure they arrive in top condition.
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Universal Drugstore does not bill private health insurance directly, but we provide a detailed invoice that you can submit to your insurer for possible reimbursement. Many insurers will accept Universal Drugstore’s documents, but if you have any questions, check with your insurance company prior to purchasing.
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Universal Drugstore offers many generic alternatives that provide the same active ingredients at a lower cost. Search for your medication and compare pricing for generic vs. brand-name options. Generic availability depends on the medication.
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Jamie Winn, PharmD, is a licensed pharmacist and seasoned medical content reviewer with over 20 years of experience in clinical pharmacy, patient care, and healthcare leadership.
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Shirley is a Medical Writer and first-year Doctor of Pharmacy (PharmD) student at the University of Alberta, where she is building on her strong foundation in health sciences and patient care.
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