Dosing and uses of Ca-DTPA (pentetate calcium trisodium)
Adult dosage forms and strengths
injectable/inhalation solution
- 1g/5mL
Internal Contamination
Contamination with plutonium, americium, or curium radionuclides
- 1 g slow IV push over 3-4 minutes OR
- IV infusion (in 100-250 mL D5W or LR or NS) OR
- Inhalation in a nebulizer (1:1 with water or saline)
- IV administration should not be protracted over >2 hours
- Can be administered undiluted by IM (off-label) if IV is not practical; coadministration of 1-2% procaine may alleviate injection site pain
- After initial decontamination, generally switched over to the less potent but less toxic Zn-DTPA if necessary
- Repeat doses may be adminnistered up to 5 days/week qDay
- Full decontamination may require prolonged treatment
Other Indications & Uses
Ca-DTPA is 10 times more effective than Zn-DTPA
Pediatric dosage forms and strengths
injectable/inhalation solution
- 1g/5mL
Internal Contamination
<12 years old: 14 mg/kg IV qDay initially; not to exceed >1 g/day
Maintenance: 14 mg/kg/day IV; not to exceed 1 g/day
>12 years old: As in adults
Ca-DTPA (pentetate calcium trisodium) adverse (side) effects
(Repeated administration over a short period)
Frequency not defined
Anosmia
Chills
Fever
Muscle cramps
Nausea
Pruritus
Vomiting
Chest pain
Dermatitis
Diarrhea
Metallic taste
Trace element deficiency
Depletion of zinc, magnesium, manganese and metalloproteinase (during prolonged treatment)
Warnings
Nephrotic synd/preexisting serious kidney dz
Bone marrow depression (eg, leukopenia, thrombocytopenia)
Not for uranium or neptunium
Obtain written consent for tx
Severe hemachromatosis
Do not divide dose
May lead to depletion of endogenous trace metals
Discontinue if diarrhea occurs
Monitor BP during infusion
Pregnancy and lactation
Pregnancy category: C
Lactation: N/A
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Ca-DTPA (pentetate calcium trisodium)
Distribution: In extracellular fluid, very little in cells/tissues
Metabolism: minimaL
Excretion: predominantly in urine, almost completely in 12 hr; feces <3%
Ca-DTPA (Akorn, Inc, call 1-800-932-5676; [inj/inh soln]: 1 g/5 mL vial)
Mechanism of action
Chelates transuranium metals
