DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more

Ca-Dtpa (Pentetate Calcium Trisodium) - Indications and Dosage

 
 



INDICATIONS AND USAGE

Ca-DTPA is indicated for treatment of individuals with known or suspected internal contamination with plutonium, americium, or curium to increase the rates of elimination.

DOSAGE AND ADMINISTRATION

Chelation treatment is most effective if administered within the first 24 hours after internal contamination and should be started as soon as possible after suspected or known internal contamination. However, even when treatment cannot be started right away, individuals should be given chelation treatment as soon as it becomes available. Chelation treatment is still effective even after time has elapsed following internal contamination however, the chelating effects of Ca-DTPA are greatest when radiocontaminants are still circulating or are in interstitial fluids. The effectiveness of chelation decreases with time following internal contamination as the radiocontaminants become sequestered in liver and bone.

Individuals should drink plenty of fluids and void frequently to promote dilution of the radioactive chelate in the urine and minimize radiation exposure directly to the bladder.

If internal contamination with radiocontaminants other than plutonium, americium, or curium, or unknown radiocontaminants is suspected, additional therapies may be needed (e.g., Prussian blue, potassium iodide).

Initial Dose

Adults and Adolescents

A single 1.0 gram initial dose of Ca-DTPA administered intravenously.

Pediatrics (less than 12 years of age)

A single initial dose of 14 mg/kg administered intravenously not exceed 1.0 gram.

Renally impaired patients

No dose adjustment is needed. However, renal impairment may reduce the rate at which chelators remove radiocontaminants from the body. In heavily contaminated patients with renal impairment, dialysis may be used to increase the rate of elimination. High efficiency high flux dialysis is recommended. Because dialysis fluid will become radioactive, radiation precautions must be taken to protect personnel, other patients, and the general public. If Ca-DTPA is not available, proceed with treatment with Zn-DTPA as initial therapy.

Maintenance Treatment

AFTER THE INITIAL DOSE, ON THE NEXT DAY, IF ADDITIONAL CHELATION THERAPY IS INDICATED, IT IS PREFERABLE TO SWITCH TO ZN-DTPA, IF AVAILABLE (SEE ZN-DTPA LABELING) DUE TO THE SAFETY CONCERNS ASSOCIATED WITH PROLONGED CA-DTPA USE. IF ZN-DTPA IS NOT AVAILABLE, TREATMENT MAY CONTINUE WITH CA-DTPA, HOWEVER MINERAL SUPPLEMENTS CONTAINING ZINC SHOULD BE GIVEN CONCOMITANTLY, AS APPROPRIATE.

Adults and Adolescents

The recommended maintenance dose of Ca-DTPA is 1.0 gram once a day administered intravenously.

Pediatrics (less than 12 years of age)

The recommended maintenance dose of Ca-DTPA is 14 mg/kg once a day administered intravenously. The maximum daily dose should not exceed 1.0 gram per day.

Renally impaired patients

No dose adjustment is needed.

The duration of chelation treatment depends on the amount of internal contamination and individual response to treatment. (See Monitoring)

Methods of Administration

Intravenous administration of Ca-DTPA is recommended and should be used if the route of internal contamination is not known or if multiple routes of internal contamination are likely. Ca-DTPA solution (1 gram in 5 mL) should be administered either with a slow intravenous push over a period of 3-4 minutes or by intravenous infusion diluted in 100-250 mL of 5% dextrose in water (D5W), Ringers Lactate, or Normal Saline.

In individuals whose internal contamination is only by inhalation within the preceding 24 hours, Ca-DTPA can be administered by nebulized inhalation as an alternative route of administration. Ca-DTPA should be diluted for nebulization at a 1:1 ratio with sterile water or saline. After nebulization, individuals should be encouraged to avoid swallowing any expectorant. Some individuals may experience respiratory adverse events after inhalation therapy. (See WARNINGS) The safety and effectiveness of the nebulized route of administration has not been established in the pediatric population.

The safety and effectiveness of the intramuscular route of injection have not been established. (See OVERDOSE)

Handling

OPC ampoule: to open, turn so that the point faces upward and break off the neck with a downward movement.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. The product may be filtered using a sterile filter if particles are seen subsequent to opening of the ampoule.

Monitoring

When possible, obtain baseline blood and urine samples (CBC with differential, BUN, serum chemistries and electrolytes, urinalysis, and blood and urine radioassays) before initiating treatment.

Ca-DTPA must be given with very careful monitoring of serum zinc and complete blood counts. When appropriate, vitamin or mineral supplements that contain zinc should be administered. (See WARNINGS)

To establish an elimination curve, a quantitative baseline estimate of the total internalized transuranium element(s) and measures of elimination of radioactivity should be obtained by appropriate whole-body counting, by bioassay (e.g., biodosimetry), or fecal/urine sample whenever possible.

During Treatment

  • Measure the radioactivity in blood, urine, and fecal samples weekly to monitor the radioactive contaminant elimination rate.
  • Monitor CBC with differential, BUN, serum chemistries and electrolytes, and urinalysis regularly. If the individual is receiving more than one dose of Ca-DTPA, these laboratory tests should be very carefully monitored and consider mineral supplementation as appropriate. (See CLINICAL PHARMACOLOGY, Pharmacodynamics, Adverse Metabolic Effects)
  • Record any adverse events from Ca-DTPA.

HOW SUPPLIED

Ca-DTPA is supplied as a sterile solution in 5 mL single-use clear glass ampoules at a concentration of 200 mg/mL for intravenous use. Each ampoule contains the equivalent of 1000 mg of pentetate calcium trisodium.

NDC 52919-001-03, 5 mL single-use ampoules, package of 10.

Storage

Store between 15 - 30°C (59 - 86°F).

-- advertisement -- The American Red Cross
 
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2017