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Medications and Drugs

Brand Names: Fosrenol

Generic Name: lanthanum carbonate (Pronunciation: LAN than um CAR bo nayt)

What is lanthanum carbonate (Fosrenol)?

Lanthanum prevents the body from absorbing phosphate, allowing it to be removed from the body.

Lanthanum carbonate is used for reducing phosphate levels in patients with end stage renal disease. High levels of phosphate can lead to complications with calcium absorption, resulting in serious medical problems.

Lanthanum carbonate may also be used for purposes not listed in this medication guide.

Fosrenol 250 mg

round, white, imprinted with S405 250

Fosrenol 500 mg

round, white, imprinted with S405 500

What are the possible side effects of lanthanum carbonate (Fosrenol)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using lanthanum carbonate and call your doctor at once if you have a serious side effect such as severe stomach pain or severe constipation.

Less serious side effects may include:

  • nausea or vomiting;
  • diarrhea or constipation; or
  • stomach pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about lanthanum carbonate (Fosrenol)?

You should not use lanthanum carbonate if you are allergic to it, or if you have a bowel obstruction or severe constipation.

Before you take lanthanum carbonate, tell your doctor if you have a stomach ulcer, ulcerative colitis, Crohn's disease, diabetes, any type of bowel obstruction, or a history of colon cancer or intestinal surgery.

The chewable tablet should be chewed completely before you swallow it.

Take lanthanum carbonate with food or immediately after eating.

Tell your doctor about all other medicines you use, especially antibiotics, seizure medication, heart or blood pressure medication, or a blood thinner.

If you also take thyroid replacement medication, take it at least 2 hours before or after taking lanthanum carbonate. Do not take thyroid medication and lanthanum carbonate at the same time.

Avoid taking an antacid within 2 hours before or after you take lanthanum carbonate. Some antacids can make it harder for your body to absorb lanthanum carbonate.

If you need to have any type of x-ray or CT scan using a dye that is injected into your veins, tell the doctor ahead of time that you are using lanthanum carbonate.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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