A-Z Drug Facts > Etidronate Disodium

Etidronate Disodium

Pronunciation: (eh-TIH-DROE-nate die-SO-dee-uhm)
Class: Bisphosphonate

Trade Names:
Didronel
- Tablets 200 mg
- Tablets 400 mg

CO Etidronate (Canada)
Gen-Etidronate (Canada)

Pharmacology

Inhibits normal and abnormal bone resorption; reduces bone formation.

Pharmacokinetics

Absorption

Approximately 3% is absorbed.

Distribution

Approximately 50% of the absorbed dose is distributed to bone compartments. Does not cross blood-brain barrier.

Metabolism

Not metabolized.

Elimination

The t _½ is 1 to 6 h. In animals, bone Cl is 165 days. Unabsorbed drug excreted in feces. Approximately 50% of the absorbed dose is excreted in the urine within 24 h.

Indications and Usage

Treatment of symptomatic Paget disease; prevention and treatment of heterotopic ossification following total hip replacement or caused by spinal cord injury.

Unlabeled Uses

Treatment of corticosteroid-induced osteoporosis.

Contraindications

Hypersensitivity to bisphosphonates; clinically overt osteomalacia.

Dosage and Administration

Paget Disease
Adults

PO Initial treatment is 5 to 10 mg/kg/day (not to exceed 6 mo) or 11 to 20 mg/kg/day (not to exceed 3 mo). Reserve doses greater than 10 mg/kg/day for specific situations. For retreatment, initiate only after etidronate-free period of at least 90 days and if there is evidence of active disease.

Heterotopic Ossification from Spinal Cord Injury
Adults

PO 20 mg/kg/day for 2 wk followed by 10 mg/kg/day for 10 wk; total treatment period is 12 wk.

Heterotopic Ossification Complicating Total Hip Replacement
Adults

PO 20 mg/kg/day for 1 mo preoperatively followed by 20 mg/kg/day for 3 mo postoperatively.

General Advice

• Administer prescribed dose on an empty stomach at least 2 h before or after food, vitamins with minerals, or antacids high in calcium, iron, magnesium, or aluminum.
• May administer in divided doses if GI side effects (eg, nausea, diarrhea) are bothersome.
• Have patient swallow tablet(s) whole with a full glass (6 to 8 oz) of plain water.

Storage/Stability

Store tablets away from excessive heat (less than 104°F).

Drug Interactions

Antacid, calcium, other cations

Decreased etidronate absorption.

Food

Absorption of etidronate is decreased by food.

Laboratory Test Interactions

None well documented.

Adverse Reactions

CNS

Amnesia, confusion, depression, hallucination, headache, paresthesias (postmarketing).

Dermatologic

Alopecia, Stevens-Johnson syndrome (postmarketing).

GI

Diarrhea; nausea; diarrhea in enterocolitis patients; esophagitis, gastritis, glossitis, exacerbation of peptic ulcer disease, perforation of peptic ulcer (postmarketing).

Genitourinary

Abnormal elevations of serum creatinine; mild to moderate abnormalities in renal function.

Hematologic

Agranulocytosis, pancytopenia, leukopenia (postmarketing).

Musculoskeletal

Arthropathies including arthralgia and arthritis, bone fracture, leg cramps, osteomalacia (postmarketing).

Respiratory

Exacerbation of asthma (postmarketing).

Miscellaneous

Hypersensitivity (eg, angioedema, urticaria, rash, pruritus); increased or recurrent bone pain in Paget disease; hypocalcemia; nephrotic syndrome and fractures with excessive doses; hyperphosphatemia.

Precautions

Monitor Documentation Document dates of previous treatment with etidronate.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Bone turnover

Etidronate suppresses bone turnover and may retard mineralization of osteoid laid down during bone accretion process.

Calcium/Vitamin D intake

Ensure that patient's daily calcium and vitamin D intake are evaluated before starting therapy and that calcium and/or vitamin D supplementation is being used in patient with inadequate daily intake.

GI disorders

Use this drug with caution in patients with active upper GI problems such as dysphagia (difficulty swallowing); symptomatic esophageal diseases; gastritis; duodenitis or ulcers.

Paget disease

Response may be slow and may continue for months after treatment has been discontinued. Dosage must not be prematurely increased or treatment prematurely reinitiated until patient has had at least 90-day etidronate-free interval.

Reduced glomerular filtration

Decrease etidronate dosage.

Overdosage

Symptoms

Diarrhea, vomiting, hypocalcemia.

Patient Information

• Advise patient to read patient package insert before starting therapy and to reread the insert each time the medication is renewed.
• Advise patient to take tablets on an empty stomach, 2 h before or after food, multivitamins with minerals, or antacids high in calcium, iron, magnesium, or aluminum.
• Instruct patient to take each dose with 6 to 8 oz of plain water.
• Instruct patient to discontinue therapy and seek medical care if any of the following occur: difficulty swallowing; pain behind breastbone; new or worsening heartburn.
• Advise patient to maintain adequate intake of calcium and vitamin D with diet and/or diet and supplements.
• Advise women to notify health care provider if pregnant, planning to become pregnant, or breastfeeding.
• Instruct patient not to take any prescription or OTC medications, herbal preparations, or dietary supplements unless advised by health care provider.
• Advise patient that follow-up visits and laboratory tests may be required to monitor therapy and to keep appointments.

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