Product Description.:
ED 400
tablet , white , oblong oblong
Biconvex
Didronel tablets contain either 200 mg or 400 mg of etidronate disodium, the disodium salt of (1-hydroxyethylidene) diphosphonic acid, for oral administration. This compound, also known as EHDP, regulates bone metabolism.
Inactive Ingredients: Each tablet contains magnesium stearate, microcrystalline cellulose, and starch.
INDICATIONS
Didronel is indicated for the treatment of symptomatic Paget's disease of bone and in the prevention and treatment of heterotopic ossification following total hip replacement or due to spinal cord injury. Didronel is not approved for the treatment of osteoporosis.
Paget's Disease: Didronel is indicated for the treatment of symptomatic Paget's disease of bone. Didronel therapy usually arrests or significantly impedes the disease process as evidenced by:
--Symptomatic relief, including decreased pain and/or increased mobility (experienced by 3 out of 5 patients).
--Reductions in serum alkaline phosphatase and urinary hydroxyproline levels (30% or more in 4 out of 5 patients).
--Histomorphometry showing reduced numbers of osteoclasts and osteoblasts, and more lamellar bone formation.
--Bone scans showing reduced radionuclide uptake at pagetic lesions.
In addition, reductions in pagetically elevated cardiac output and skin temperature have been observed in some patients.
In many patients, the disease process will be suppressed for a period of at least 1 year following cessation of therapy. The upper limit of this period has not been determined.
The effects of the Didronel treatment in patients with asymptomatic Paget's disease have not been studied. However, Didronel treatment of such patients may be warranted if extensive involvement threatens irreversible neurologic damage, major joints, or major weight-bearing bones.
Heterotopic Ossification: Didronel is indicated in the prevention and treatment of heterotopic ossification following total hip replacement or due to spinal cord injury.
Didronel reduces the incidence of clinically important heterotopic bone by about two-thirds. Among those patients who form heterotopic bone, Didronel retards the progression of immature lesions and reduces the severity by at least half. Follow-up data (at least 9 months posttherapy) suggest these benefits persist.
In total hip replacement patients, Didronel does not promote loosening of the prosthesis or impede trochanteric reattachment.
In spinal cord injury patients, Didronel does not inhibit fracture healing or stabilization of the spine.
SIDE EFFECTS
The incidence of gastrointestinal complaints (diarrhea, nausea) is the same for Didronel at 5 mg/kg/day as for placebo, about 1 patient in 15. At 10 to 20 mg/kg/day the incidence may increase to 2 or 3 in 10. These complaints are often alleviated by dividing the total daily dose.
Paget's Disease: In Paget's patients, increased or recurrent bone pain at pagetic sites, and/or the onset of pain at previously asymptomatic sites has been reported. At 5 mg/kg/day about 1 patient in 10 (versus 1 in 15 in the placebo group) report these phenomena. At higher doses the incidence rises to about 2 in 10. When therapy continues, pain resolves in some patients but persists in others.
Heterotopic Ossification: No specific adverse reactions.
Worldwide Postmarketing Experience: The worldwide postmarketing experience for etidronate disodium reflects its use in the following approved indications: Paget's disease, heterotopic ossification, and hypercalcemia of malignancy. It also reflects the use of etidronate disodium for osteoporosis where approved in countries outside the US. Other adverse events that have been reported and were thought to be possibly related to etidronate disodium include the following: alopecia arthropathies, including arthralgia and arthritis bone fracture esophagitis glossitis hypersensitivity reactions, including angioedema, follicular eruption, macular rash, maculopapular rash, pruritus, a single case of Stevens-Johnson syndrome, and urticaria osteomalacia neuropsychiatric events, including amnesia, confusion, depression, and hallucination and paresthesias.
In patients receiving etidronate disodium, there have been rare reports of agranulocytosis, pancytopenia, and a report of leukopenia with recurrence on rechallenge. In addition, there have been rare reports of exacerbation of asthma. Exacerbation of existing peptic ulcer disease has been reported in a few patients. In one patient, perforation also occurred.
In osteoporosis clinical trials, headache, gastritis, leg cramps, and arthralgia occurred at a significantly greater incidence in patients who received etidronate as compared with those who received placebo.
