1 What is Didronel?

Brand: Didronel

Generic: Etidronate

Didronel is used to treat Paget’s disease of the bone. It may also be used to treat heterotopic ossification after hip replacement surgery or spinal injury.

Didronel is also used to treat hypercalcemia (too much calcium in the bone) that may occur with certain types of cancer.

This medication is only available with your doctor’s prescription. This medication is available in the following forms:

  • Tablet

2 What to Know Before Using

Before using Didronel, you must know all about the risks and complications associated with it. This is a decision that you and your doctor will make together.

For this medication, there are many things that need to be considered:

Allergies: Inform your doctor if you have ever had an allergic reaction to any other medications. It is also important to inform your doctor of any non-medicine allergies such as foods, dyes, preservatives or animals.

Pediatric: No appropriate studies have been performed on the relationship of age to the effects of this medication in children. Safety and efficacy have not been established.

Geriatric: Up-to-date studies have not shown any problems specific to the elderly that would limit the use of this medication in the elderly population. However, elderly patients are more likely to have age-related kidney, liver or heart problems, which may require an adjustment in dose.

Pregnancy: This medication is listed as Pregnancy Category C. This means that animal studies have shown an adverse effect and no studies have been performed on pregnant women OR there are no adequate studies on pregnant animals and pregnant women.

Breastfeeding: There are no up-to-date studies in women for determining infant risk when using this medication while breastfeeding. Weigh the potential risks with the benefits before taking this medication while breastfeeding.

Drug Interactions: Certain medications should not be used together. However, in certain cases, two medications may be used together, even if an interaction might occur. In these cases, your doctor may want to change your dose or take other precautions. When taking this medication, it is important that you inform your doctor if you are taking any prescription or over-the-counter medications.

Other Interactions: Certain medications should not be used while eating, or while eating certain foods in case of negative interactions. Using alcohol or tobacco with certain medications may also cause negative interactions. Talk with your doctor about the use of your medication with food, alcohol or tobacco.

Other Medical Problems: Pre-existing medical problems may affect the use of this medication.

Be sure to tell your doctor if you have any other medical problems, especially:

  • Anemia
  • Blood clotting problems
  • Cancer
  • Dental or tooth problems
  • Dental procedures (i.e. tooth extraction)
  • Infection
  • Poor oral hygiene
  • Surgery (i.e. dental surgery) - May increase risk for severe jaw problems. This risk may also be increased if you use this medicine for a long time.
  • Enterocolitis (severe diarrhea)
  • Hyperphosphatemia (high phosphate in the blood)
  • Stomach or bowel problems (i.e. Barrett's esophagus, difficulty with swallowing, heartburn, inflammation of the esophagus, or ulcers) - Use with caution. May make these conditions worse.
  • Esophageal problems (i.e. achalasia, stricture)
  • Osteomalacia (soft bones)
  • Trouble with swallowing - Should not be used in patients with these conditions.
  • Kidney disease - Use with caution. The effects may be increased because of slower removal of the medicine from the body.

3 Proper Usage

Proper usage of Didronel requires strict adherence to your doctor’s orders. Do not take more, less or for a longer or shorter period of time than your doctor tells you.

This medication comes with a patient information brochure. It is very important that your read this information. Ask your doctor if you have any questions.

Inform your doctor if your diet includes large amounts of calcium or if you are on a special diet such as low-sodium or low-sugar diets. Calcium in the diet may prevent the absorption of this medication.

Take this medication with a full glass of water on an empty stomach at least 2 hours before or after food or at bedtime. Food may decrease the amount of medication absorbed by your system.

Do not lie down for at least 30 minutes after taking this medication and do not lie down until after you have eaten some food.

This medication may take up to 3 months to work. If you feel that the medication is not working, do not stop taking it on your own.

It is important to eat a well-balanced diet with an adequate amount of calcium and vitamin D. Too much or too little of these may increase the chance of side effects while taking this medication.

Your doctor can help you choose a meal plan. However, do not take any foods that are high in calcium or iron, magnesium or aluminum within 2 hours of taking this medication. This may keep the medication from working properly.

If this medication upsets your stomach, ask your doctor if you can take two smaller doses instead of one larger dose. Do not change the way you take this medication without asking your doctor.

You may take this medication for up to 6 months to treat Paget’s disease. After 90 days of not taking the medication, your doctor may want you to start another course of treatment.

If you have Paget’s disease, this medication may work slowly and you may not feel better until you have been using it for a long time. Do not stop taking it without talking to your doctor first. Your body may continue to respond to this medication after you stop using it.

Dosing: Different patients will be given a different dose of this medication based on the strength of the medication. The number of doses you take each day, the time between doses and the length of time you take this medication depends on the reason you are taking this medication.

The following information only includes the average dose of this medication. If your dose is different, do not change it without first speaking to your doctor.


For Paget’s disease of bone:

  • Adults - Dose is based on body weight and must be determined by your doctor. Start with 5mg per kilogram of body weight per day, normally as a single dose, for up to 6 months. Some may need 6-10mg per kilogram of body weight per day for up to 6 months. Others may need 11-20mg per kilogram of body weight per day for up to 3 months. Your doctor may adjust your dose depending on how you respond to the treatment.
  • Children - Use and dose must be determined by your doctor.

For treating or preventing a certain type of bone problem that may occur after hip replacement:

  • Adults - Dose is based on body weight and must be determined by your doctor. The dose is normally 20mg per kilogram of body weight a day for 1 month before surgery and for 3 months after surgery.
  • Children - Use and dose must be determined by your doctor.

For treating and preventing a certain type of bone problem that may occur after spinal injury:

  • Adults - Dose is based on body weight and must be determined by your doctor. The dose is normally 20mg per kilogram of body weight a day for 2 weeks, beginning as soon as possible after your injury. Your doctor may then decrease the dose to 10mg per kilogram of body weight for 10 weeks.
  • Children - Use and dose must be determined by your doctor.

For treating hypercalcemia (too much calcium in the blood):

  • Adults - Dose is based on body weight and must be determined by your doctor. The dose is normally 20mg per kilogram of body weight per day for 30 days. Treatment usually does not continue beyond 90 days.
  • Children - Use and dose must be determined by your doctor.

Missed dose: If you miss a dose of this medication, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and resume your normal dosing schedule. Do not double dose.

Storage: Store this medication in a closed container at room temperature. Keep it away from heat, moisture, and direct light. Do not freeze. Keep our of the reach of children.

Do not keep expired medication or medication you no longer need. Ask your doctor how to dispose of any medication you do not use.

4 Precautions to Take

In using Didronel, you must be careful and take some precautions as advised by your doctor. This medication may irritate your esophagus. If you think this medication has started to damage your esophagus, stop taking this medication and call your doctor.

Some symptoms of damage to the esophagus are heartburn, pain when swallowing, pain in the center of your chest, difficulty swallowing or feeling as if food gets stuck on the way to your stomach. Do not take other prescription or over-the-counter medications without asking your doctor.

It is important that you tell all of your healthcare professionals that you are taking etidronate. If you have to have any dental procedures done while taking this medication, you may have an increased chance of developing a severe problem of your jaw.

Be sure to tell your doctor about any new medical problems, especially with your teeth or jaws. Tell your doctor if you have severe bone, joint or muscle pain while using this medication. If this medication causes you to have continuing nausea or diarrhea. The dose may need to be changed.

This medication may increase your risk of developing fractures. This may be more common if you use it for a long time. Inform your doctor immediately if you have a dull or aching pain in the arms, legs or thighs.

5 Potential Side Effects

As with many medications, there are several potential side effects associated with Didronel. Although not all of these side-effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if you experience any of the following side-effects:

More common:

  • Bone pain or tenderness (increased, continuing or returning).

Less common:

  • Bone fractures, especially in the thigh bone


  • Abdominal or stomach pain or burning
  • Bloody, black, or tarry stools
  • Chest pain
  • Chills
  • Cough or hoarseness
  • Fever
  • General feeling of tiredness or weakness
  • Hives
  • Lower back or side pain
  • Noisy breathing
  • Painful or difficult urination
  • Pale skin
  • Skin rash or itching
  • Sore throat
  • Sores, ulcers, or white spots on the lips or inside the mouth
  • Swelling of the arms, legs, face, lips, tongue, or throat
  • Swollen glands
  • Tightness in the chest
  • Unusual bleeding or bruising

Get emergency help immediately if any of the following symptoms of overdose occur:

  • Abdominal or stomach cramps
  • Confusion
  • Convulsions
  • Difficulty in breathing
  • Irregular heartbeats
  • Mood or mental changes
  • Muscle cramps in the hands, arms, feet, legs, or face
  • Numbness and tingling around the mouth, fingertips, or feet
  • Shortness of breath
  • Tremor

Some side effects that may occur do not normally need medical attention. These may leave as your body becomes accustomed to treatment. Ask your doctor about ways to prevent or reduce some of these side effects.

Talk to your doctor if any of the following side effects continue or are bothersome, or if you have questions:

More common:

Some patients may experience other side effects that are not listed. Check with your doctor if you notice any other side effects. Ask your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.