Medically reviewed by Drugs.com. Last updated on Sep 5, 2021.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
- Tablet, Chewable
Therapeutic Class: Phosphate Binder
Uses for Fosrenol
Lanthanum is used to treat hyperphosphatemia (too much phosphate in the blood) in patients with end stage kidney disease who are on dialysis.
This medicine is available only with your doctor's prescription.
Before using Fosrenol
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of lanthanum in the pediatric population. Safety and efficacy have not been established. Use is not recommended in children.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of lanthanum in the elderly.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Mycophenolate Mofetil
- Mycophenolic Acid
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Bowel blockage (eg, ileus) or
- Fecal impaction (blockage in the rectum)—Should not be used in patients with these conditions.
- Bowel or stomach surgery, history of or
- Colon cancer, history of or
- Colon problems (eg, diverticular disease, peritonitis) or
- Constipation or
- Diabetes—May increase risk for stomach or bowel blockage.
- Crohn's disease or
- Peptic ulcer or
- Ulcerative colitis—Use of lanthanum has not been studied in patients with these medical problems.
Proper use of Fosrenol
Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.
It is best to take this medicine with or immediately right after meals.
Chew or crush the tablet completely before swallowing. Do not swallow the tablet whole.
If you cannot chew the tablets, use the oral powder form of this medicine. Sprinkle it on a small quantity of applesauce or other similar food. Mix and take it immediately. Do not mix it with water or other liquid.
Follow carefully any diet program your doctor may recommend.
If you take levothyroxine, an antacid that contains aluminum, calcium, or magnesium, an antibiotic medicine (eg, ampicillin, tetracycline), blood pressure medicine, statins, or anti-malarials, take them 2 hours before or after taking lanthanum.
If you are taking antibiotic medicines (eg, ciprofloxacin or levofloxacin), take them at least 1 hour before or 4 hours after you take lanthanum. If you need help deciding the best time to take your other medicines, ask your doctor or pharmacist.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (chewable tablets or powder):
- For high phosphorus levels in the blood:
- Adults—At first, 1500 milligrams (mg) per day, divided into small doses. Your dose will be determined and adjusted by your doctor depending on how high your blood phosphorus level is.
- Children—Use is not recommended.
- For high phosphorus levels in the blood:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using Fosrenol
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests will be needed to check for unwanted effects.
This medicine may increase your risk of having bowel blockage, a tear or hole in your stomach or bowels, or severe constipation. Talk to your doctor if you have concerns.
Make sure any doctor or dentist who treats you knows that you are using this medicine. It may affect the results of certain medical tests (eg, abdominal or stomach x-ray).
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Fosrenol side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Stomach pain
Incidence not known
- Bloody, black, or tarry stools
- bone pain
- constipation, severe
- difficulty having a bowel movement
- itching, skin rash
- loss of appetite
- severe stomach pain, cramping, or burning
- trouble breathing
- unusual tiredness or weakness
- vomiting of material that looks like coffee grounds, severe and continuous
- vomiting, severe
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
- stomach discomfort or upset
- tooth injury
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about Fosrenol (lanthanum carbonate)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Images
- Drug Interactions
- Pricing & Coupons
- En Español
- 4 Reviews
- Generic Availability
- Drug class: phosphate binders
- FDA Approval History
Related treatment guides
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