Drug information of Etidronic Acid

Etidronic Acid

Drug group:

A diphosphonate which affects calcium metabolism. It inhibits ectopic calcification and slows down bone resorption and bone turnover.


 Etidronic acid affects calcium metabolism and inhibits bone resorption and soft tissue calcification. Of the etidronic acid that is resorbed (from oral preparation) or infused (for intravenous drugs), about 50% is excreted unchanged by the kidney.

The remainder has a very high affinity for bone tissue, and is rapidly absorbed onto the bone surface. Etidronic acid has been shown to prevent or delay skeletal-related events and decrease bone pain as well as normalize calcium levels in the presence of hypercalcemia.


Absorption: The amount of drug absorbed after an oral dose is approximately 3%.

Volume of distribution: Not Available

Protein binding: Not Available

Metabolism: Not metabolized.

Route of elimination: Etidronate disodium is not metabolized. Within 24 hours, approximately half the absorbed dose is excreted in urine; the remainder is distributed to bone compartments from which it is slowly eliminated. Unabsorbed drug is excreted intact in the feces.

Half life: In normal subjects, plasma half-life of etidronic acid, based on non-compartmental pharmacokinetics is 1 to 6 hours.

Drug contraindications

severe hypersensitivity reactions


Warfarin , Aspirin


  • Bone/joint/muscle pain: Infrequently, severe (and occasionally debilitating) bone, joint, and/or muscle pain have been reported during bisphosphonate treatment. The onset of pain ranged from a single day to several months. Consider discontinuing therapy in patients who experience severe symptoms; symptoms usually resolve upon discontinuation.
  • Fracture risk: Do not exceed recommended dose or use continuously for >6 months in patients with Paget's disease; risk of osteomalacia or fractures may be increased. Long bones with predominantly lytic lesions may be prone to fracture, particularly in patients unresponsive to treatment.
  • Gastrointestinal mucosa irritation: May cause irritation to upper gastrointestinal mucosa. Esophagitis, dysphagia, esophageal ulcers, esophageal erosions, and esophageal stricture (rare) have been reported with oral bisphosphonates; risk increases in patients unable to comply with dosing instructions. Use with caution in patients with dysphagia, esophageal disease, gastritis, duodenitis, or ulcers (may worsen underlying condition). Discontinue use if new or worsening symptoms develop.
  • Osteonecrosis of the jaw: Osteonecrosis of the jaw (ONJ), also referred to as medication-related osteonecrosis of the jaw (MRONJ), has been reported in patients receiving bisphosphonates; this has been observed primarily following dental procedures such as tooth extractions and in cancer patients receiving IV bisphosphonates, but has also occurred in patients with postmenopausal osteoporosis and other diagnoses receiving oral bisphosphonates.
  • Enterocolitis: Use with caution in patients with enterocolitis; diarrhea has been reported at high doses and therapy may need to be withheld.
  • Renal impairment: Use with caution in patients with renal impairment.

Points of recommendation

To make sure this medicine is safe for you, tell your doctor if you have:

  • If you have an allergy to etidronate or any other part of etidronate.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: A swallowing tube (esophagus) that is not normal, low calcium levels, soft bones (osteomalacia), or trouble swallowing.
  • If you are not able to stand or sit up for 30 minutes.

Very bad swallowing tube (esophagus) problems like irritation, swelling, ulcers, and bleeding have happened with etidronate. Talk with the doctor.

Worsening of asthma has happened in people taking drugs like this one. Talk with the doctor.

This medicine may raise the chance of a broken leg. Talk with the doctor.

Have a bone density test as you have been told by your doctor. Talk with your doctor.

This medicine works best when used with calcium/vitamin D and weight-bearing workouts like walking or PT (physical therapy).

Follow the diet and workout plan that your doctor told you about.

Have a dental exam before starting etidronate.

Take good care of your teeth. See a dentist often.

Talk with your doctor before you drink alcohol.

If you smoke, talk with your doctor.

If you are taking warfarin, talk with your doctor. You may need to have your blood work checked more closely while you are taking it with etidronate.

Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using etidronate while you are pregnant.

Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

Take on an empty stomach. Take 2 hours before or 2 hours after meals. Swallow whole. Do not chew, break, or crush. Take with a full glass of water.

Take with plain water only. Avoid taking with mineral water, milk, or other drinks.

Do not take calcium, iron, vitamins with minerals, or antacids within 2 hours of etidronate.

Do not lie down for at least 30 minutes after taking etidronate.

To gain the most benefit, do not miss doses.

Keep taking etidronate as you have been told by your doctor or other health care provider, even if you feel well.

Take a missed dose as soon as you think about it.

If it is close to the time for your next dose, skip the missed dose and go back to your normal time. Do not take 2 doses at the same time or extra doses.

Pregnancy level


Related drugs

Alendronate , Ibandronic , Pamidronate

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