Risedronate belongs to a group of medications called bisphosphonates. It is used to treat and prevent osteoporosis for women who are past menopause, and to treat and prevent osteoporosis caused by treatment with corticosteroids (e.g., prednisone) for men and women. It is also used to improve bone mineral density for men with osteoporosis, and to treat a condition called Paget's disease. The long-acting form of risedronate is used only to treat osteoporosis in women who are past menopause.

Risedronate increases the thickness of bone (bone mineral density) by slowing down the cells that usually break down bone (osteoclasts). This allows the cells that build bone (osteoblasts) to work more efficiently. By making bones stronger, risedronate can help to reduce the incidence of osteoporosis-related fractures.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

For preventing osteoporosis in women who are past menopause, the recommended dose of the delayed release formulation of risedronate is 35 mg once weekly.

The delayed release 35 mg tablet should be taken in the morning with breakfast to reduce the likelihood of experiencing upper abdominal pain.

This medication should be taken while sitting in an upright position and swallowed whole (not chewed) with at least a half glass of water (i.e., at least 120 mL). Do not lie down for at least 30 minutes after taking the medication to prevent any irritation to your esophagus (the tube connecting the mouth and stomach).

If you are taking calcium supplements or aluminum-, iron-, or magnesium-containing medications (e.g., antacids and mineral supplements), you should take them at a different time of day. When taken together with risedronate, they will decrease the amount of risedronate that is delivered from your stomach into your body and reduce the effectiveness of the risedronate.

If you are taking this medication on a once-weekly basis and you forget to take it on the regularly scheduled day, take one tablet on the day you first remember. Then, return to taking one tablet once a week on your regularly scheduled day. Do not take 2 tablets on the same day.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Each delayed-release, oval, yellow tablet with "EC 35" engraved on one face contains the equivalent of 35 mg of anhydrous risedronate sodium in the form of the hemi-pentahydrate with small amounts of monohydrate. Nonmedicinal ingredients: edetate disodium, ferric oxide yellow, magnesium stearate, methacrylic acid copolymer dispersion, silicified microcrystalline cellulose, polysorbate 80, simethicone, sodium starch glycolate, stearic acid, talc, and triethyl citrate.

Do not take risedronate if you:

• are allergic to risedronate or any ingredients of this medication
• have low levels of calcium in the blood

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• constipation
• diarrhea
• flu-like symptoms (e.g., fever, sore throat)
• heartburn
• leg cramps
• nausea
• pain in bones, muscles, or joints
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• delayed healing and infection of mouth and jaw (usually after tooth extraction)
• difficulty swallowing
• new or unusual pain in the hip, groin or thigh (symptoms of fracture in the thigh bone)
• numbness, tingling, or muscle spasms (signs of low levels of calcium)
• painful tongue or mouth sores
• severe pain in bones, muscles, or joints
• signs of jaw bone problems (e.g., jaw numbness, loose teeth, exposed bone in mouth, discharge, dry mouth, gum swelling, bad breath, pain in mouth, teeth or jaw)
• vision changes or eye pain or inflammation

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of damage to the esophagus (e.g., pain in the esophagus [throat area] or behind the breastbone, chest pain, difficulty swallowing, pain when swallowing, or new or worsening heartburn)
• symptoms of a severe allergic reaction (e.g., swelling of the hands, feet, ankles, face, lips, mouth, or throat; difficulty breathing or swallowing)
• symptoms of a stomach or intestinal ulcer (e.g., nausea, vomiting, abdominal pain, loss of weight or appetite, black or bloody stools, or vomiting blood)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Atypical femur fracture: There is evidence that long-term use of this class of medication may contribute to a type of rare fracture of the long bone in the thigh (femur) without any form of trauma.

If you experience new or unusual pain in the groin, hip, or thigh area, contact your doctor as soon as possible.

Bone, joint, and muscle problems: On rare occasions, people taking this medication experience severe bone, joint, or muscle pain. This pain usually goes away when the medication is stopped.

Calcium and vitamin D: Calcium and vitamin D are important contributors to bone growth and strength. It may be necessary to take calcium or vitamin D supplements to get the best effect from risedronate if you are not getting enough from your diet. Your doctor may test you for low calcium levels or vitamin D deficiency before you start taking risedronate.

Effects on the esophagus: Risedronate can cause irritation or ulcers of the esophagus (the passage from the throat to the stomach). In some cases, these effects have been severe and have required hospitalization. Stop taking the medication and contact your doctor immediately if you suddenly experience problems swallowing, find it painful to swallow, develop pain behind the sternum (breastbone), or have new or worsening heartburn.

To reduce the risk of irritation of the esophagus, swallow this medication with a full glass of plain water first thing in the morning when you get up. Do not lie down until 30 minutes have passed and you have eaten your first food of the day. Do not chew or suck on the tablet, as this may lead to ulcers in the mouth or throat. Do not take this medication at bedtime or before getting up for the day.

Effects on the stomach and intestines: Rarely, people taking this medication have developed ulcers of the stomach or intestines. Get immediate medical attention if you have symptoms of a stomach or intestinal ulcer, such as nausea, vomiting, abdominal pain, loss of weight or appetite, black or bloody stools, or vomiting blood.

If you have a history of ulcer or other stomach problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Inflammation of the eye: Conditions of eye inflammation have been reported by people using risedronate. If you experience changes to your vision, red eyes, or eye pain, contact your doctor as soon as possible.

Jaw problems: Rarely, risedronate can cause severe jaw problems associated with delayed healing and infection, especially in people with cancer or after tooth extractions. Your doctor may ask you to see your dentist before you start taking this medication. Any necessary dental procedures should be completed before starting treatment with risedronate. It is important that you take good care of your teeth and gums while taking this medication. If you experience any mouth sores or pain in the jaw or teeth, contact your doctor as soon as possible.

Kidney function: Risedronate is removed from the body by the kidneys. Decreased kidney function may cause an increase in the amount of medication in the body, causing side effects. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Risedronate is not recommended for use by people with severely reduced kidney function.

People who cannot stand or sit upright for at least 30 minutes: This medication can cause irritation or ulcers of the esophagus (the tube connecting the mouth and stomach). People who cannot stand or sit upright for at least 30 minutes should use risedronate only if the benefits outweigh the risks.

Pregnancy: Risedronate is not intended for use during pregnancy. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if risedronate passes into breast milk. Risedronate is not intended for use by women who are breast-feeding. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

There may be an interaction between risedronate and any of the following:

• aminoglycoside antibiotics (e.g., amikacin, gentamicin, tobramycin)
• antacids (e.g., aluminum hydroxide, calcium carbonate, magnesium hydroxide)
• celecoxib
• deferasirox
• H2 antagonists (e.g., famotidine, nizatidine)
• non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, ketorolac, naproxen)
• paromomycin
• proton pump inhibitors (e.g., lansoprazole, omeprazole)
• systemic angiogenesis inhibitors (e.g., axitinib, bevacizumab, lenalidomide, pazopanib, regorafenib, vandetanib)
• supplements containing minerals such as aluminum, calcium, iron, magnesium, selenium and zinc

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.