Etidronate Disodium

Pronunciation

(e ti DROE nate dye SOW dee um)

U.S. Brand Names

Didronel®

Synonyms

EHDP; Sodium Etidronate

Generic Available

Canadian Brand Names

Didronel®; Gen-Etidronate

Use

Symptomatic treatment of Paget's disease and heterotopic ossification due to spinal cord injury or after total hip replacement, hypercalcemia associated with malignancy

Pregnancy Risk Factor

Pregnancy Implications

Teratogenic effects have been reported in some but not all animal studies. There are no adequate and well-controlled studies in pregnant women. Bisphosphonates are incorporated into the bone matrix and gradually released over time. Theoretically, there may be a risk of fetal harm when pregnancy follows the completion of therapy. Based on limited case reports with pamidronate, serum calcium levels in the newborn may be altered if administered during pregnancy.

Lactation

Excretion in breast milk unknown/use caution

Contraindications

Hypersensitivity to biphosphonates or any component of the formulation; serum creatinine >5 mg/dL

Warnings/Precautions

Use with caution in patients with restricted calcium and vitamin D intake; dosage modification required in renal impairment; I.V. form may be nephrotoxic and should be used with caution, if at all, in patients with impaired renal function (serum creatinine: 2.5-4.9 mg/dL)

Adverse Reactions

>10%: Neuromuscular & skeletal: Bone pain (10% to 20%, Paget's)

1% to 10%:

Central nervous system: Fever (9%), convulsions (3%)

Endocrine & metabolic: Hypophosphatemia (3%), hypomagnesemia (3%), fluid overload (6%), hypercalcemia of malignancy

Gastrointestinal: Diarrhea and nausea (7% to 30%, dose related), constipation (3%), abnormal taste (3%)

Hepatic: LFT changes (3%)

Respiratory: Dyspnea (3%)

Renal: Increased serum creatinine (10%)

<1%: Pain, angioedema, rash, occult blood in stools, increased risk of fractures, nephrotoxicity, hypersensitivity reactions, urticaria

Postmarketing and/or case reports: Osteonecrosis

Overdosage/Toxicology

Symptoms of overdose include diarrhea, nausea, vomiting, paresthesias, tetany, and coma. Antidote is calcium.

Drug Interactions

Foscarnet and plicamycin may have additive hypocalcemic effect

Ethanol/Nutrition/Herb Interactions

Food: Food decreases the absorption and bioavailability of the drug.

Stability

Store ampuls at room temperature and avoid excess heat (>40°C/104°F); intravenous solution diluted in

250 mL normal saline is stable for 48 hours at room temperature or refrigerated

Mechanism of Action

Decreases bone resorption by inhibiting osteocystic osteolysis; decreases mineral release and matrix or collagen breakdown in bone

Pharmacodynamics/Kinetics

Onset of action: 1-3 months

Duration: Can persist for 12 months without continuous therapy

Absorption: Dose dependent

Metabolism: None

Excretion: Primarily urine (as unchanged drug); feces (as unabsorbed drug)

Dosage

Adults: Oral formulation should be taken on an empty stomach 2 hours before any meal.

Paget's disease: Oral

Initial: 5-10 mg/kg/day (not to exceed 6 months) or 11-20 mg/kg/day (not to exceed 3 months). Doses >10 mg/kg/day are not recommended.

Retreatment: Initiate only after etidronate-free period 90 days. Monitor patients every 3-6 months. Retreatment regimens are the same as for initial treatment.

Heterotopic ossification: Oral:

Caused by spinal cord injury: 20 mg/kg/day for 2 weeks, then 10 mg/kg/day for 10 weeks; total treatment period: 12 weeks

Complicating total hip replacement: 20 mg/kg/day for 1 month preoperatively then 20 mg/kg/day for 3 months postoperatively; total treatment period is 4 months

Hypercalcemia associated with malignancy:

I.V. (dilute dose in at least 250 mL NS): 7.5 mg/kg/day for 3 days; there should be at least 7 days between courses of treatment

Oral: Start 20 mg/kg/day on the last day of infusion and continue for 30-90 days

Dosing adjustment in renal impairment:

Scr 2.5-5 mg/dL: Use with caution

Scr >5 mg/dL: Not recommended

Administration

Administer intravenous dose over at least 2 hours; tablet should be administered on an empty stomach 2 hours before meals

Monitoring Parameters

Serum calcium and phosphorous; serum creatinine and BUN

Reference Range

Calcium (total): Adults: 9.0-11.0 mg/dL

Dietary Considerations

Administer tablet with water, black coffee, tea, or fruit juice on an empty stomach; avoid administering foods/supplements with calcium, iron, or magnesium within 2 hours of drug; maintain adequate intake of calcium and vitamin D.

Patient Education

Inform prescriber of all prescriptions, OTC medications, or herbal products you are taking, and any allergies you have. Do not take any new medication during therapy unless approved by prescriber. Take with water, black coffee, tea, or fruit juice on an empty stomach 2 hours before food, other medications, or dietary supplements. Consult prescriber to determine necessity of dietary supplements of calcium, or increased dietary vitamin D. You may experience nausea or vomiting (small frequent meals may heal); diarrhea (boiled milk, or yogurt may help); bone pain (consult prescriber for analgesic). Report muscle twitching, usual fever, convulsions, difficulty breathing, rash, bloody stool, or other persistent adverse effects. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant or if you are breast-feeding.

Nursing Implications

Ensure adequate hydration

Dental Health: Effects on Dental Treatment

Key adverse event(s) related to dental treatment: Abnormal taste.

Dental Health: Vasoconstrictor/Local Anesthetic Precautions

No information available to require special precautions

Mental Health: Effects on Mental Status

None reported

Mental Health: Effects on Psychiatric Treatment

Bisphosphonates have been associated with renal toxicity manifested as deterioration of renal function and potential renal failure. Use caution in patients receiving lithium.

Oncology: Emetic Potential

Low

Oncology: Vesicant

No; there are no reports in the literature detailing extravasation or its consequences

Dosage Forms

Injection, solution: 50 mg/mL (6 mL)

Tablet: 200 mg, 400 mg

References

French AE, Kaplan N, Lishner M, et al, "Taking Bisphosphonates During Pregnancy," Can Fam Physician , 2003, 49:1281-2.

Gray RE, "Severe Reaction to Diphosphonate," BMJ , 1988, 297(6655):1042.

Ruggiero SL, Mehrotra B, Rosenberg TJ, et al, "Osteonecrosis of the Jaws Associated With the Use of Bisphosphonates: A Review of 63 Cases," J Oral Maxillofac Surg , 2004, 62(5):527-34.

Storm T, Thamsborg G, Steiniche T, et al, "Effect of Intermittent Cyclical Etidronate Therapy on Bone Mass and Fracture Rate in Women With Postmenopausal Osteoporosis," N Engl J Med , 1990, 322(18):1265-71.

Watts NB, Harris ST, Genant HK, et al, "Intermittent Cyclical Etidronate Treatment of Postmenopausal Osteoporosis," N Engl J Med , 1990, 323(2):73-9.

International Brand Names

Dibronat® (TR); Didronate® (DK, FI, NO, SE); Didronat® (TR); Didronel® (AT, AU, BE, CA, CH, DE, FR, GB, HK, IE, IL, JP, LU, NZ); Didronel Europharma DK® (DK); Didronel Orifarm® (DK); Didronel Paranova® (DK); Difosfen® (CO, CR, DO, ES, GT, PA, PL, SG, SV); Diphos® (DE); Dronate-Os® (IN); Etidrate® (NZ); Etidronat Jenapharm® (DE); Etidron Hexal® (DE); Etidron® (IT); Gen-Etidronate (CA); Ostedron® (PL); Osteodidronel® (BE); Osteotop® (CL); Osteum® (ES); Pleostat® (HR, RU, SI)

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process . A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Home > Medical Reference > Complementary Medicine