Usage
- Disodium edetate is prescribed for the treatment of hypercalcemia (high blood calcium levels) and for controlling heart rhythm disturbances caused by digitalis toxicity (e.g., digoxin overdose). It is also used for lead poisoning, removing toxic and radioactive metals, and digitalis-induced cardiac arrhythmias.
- Pharmacological Classification: Chelating agent.
- Mechanism of Action: Disodium edetate acts by chelating (binding to) divalent and trivalent metal ions, such as calcium, lead, zinc, and magnesium. This forms stable, water-soluble complexes that are then excreted by the kidneys, effectively lowering the concentration of these ions in the blood.
Alternate Names
- Disodium EDTA
- EDTA disodium salt
- Edetate disodium salt dihydrate
- Ethylenediaminetetraacetic acid disodium salt dihydrate
- Disodium ethylenediaminetetraacetate dihydrate
- EDTA-Na₂
- Edathamil
- Sequestrene Na₂
- Brand Names: Disotate, Endrate (discontinued)
How It Works
- Pharmacodynamics: Disodium edetate lowers blood calcium levels by forming stable complexes with calcium ions, which are then excreted renally. It also chelates other metal ions like lead, zinc, and magnesium. In cases of digitalis toxicity, it can help restore normal heart rhythm by reducing calcium-mediated effects on cardiac muscle.
- Pharmacokinetics: Administered intravenously. Disodium EDTA is primarily eliminated through renal excretion, with minimal hepatic metabolism. The chelated complexes are rapidly cleared by glomerular filtration.
- Mode of Action: Binds divalent and trivalent cations, forming stable, water-soluble complexes. This reduces their free concentration and facilitates their excretion.
- Receptor Binding, Enzyme Inhibition, or Neurotransmitter Modulation: Disodium edetate primarily acts through chelation rather than receptor binding, enzyme inhibition, or neurotransmitter modulation.
- Elimination Pathways: Primarily renal excretion as chelates.
Dosage
Standard Dosage
Adults:
- 50 mg/kg/day up to a maximum of 3 g in 24 hours, administered by slow intravenous infusion over 3-4 hours. A common regimen is 5 consecutive daily doses, followed by 2 days without medication, repeated as needed up to a total of 15 doses.
Children:
- 40 mg/kg/day (1 g per 25 kg) up to a maximum of 70 mg/kg/24 hours. Dilute in a sufficient volume of 5% Dextrose Injection or 0.9% Sodium Chloride Injection to a final concentration not exceeding 3%. Administer by slow intravenous infusion over 3-4 hours.
- Pediatric Safety Considerations: Closely monitor renal function. Avoid rapid IV infusions, especially in lead encephalopathy.
Special Cases:
- Elderly Patients: Adjust dose based on renal function.
- Patients with Renal Impairment: Reduce dosage based on creatinine clearance.
- Patients with Hepatic Dysfunction: Caution is advised, though minimal hepatic metabolism occurs.
- Patients with Comorbid Conditions: Monitor closely in patients with diabetes, cardiovascular disease, and electrolyte imbalances.
Clinical Use Cases
Dosing guidelines based on the specific clinical scenario and overseen by a physician. Similar dosages to the standard dosage recommendations may be used.
- Intubation: No specific dosing recommendations for intubation procedures.
- Surgical Procedures: No specific dosing recommendations.
- Mechanical Ventilation: No specific dosing recommendations.
- Intensive Care Unit (ICU) Use: Dosage adjustments may be necessary depending on the clinical picture and organ function.
- Emergency Situations: Doses up to 75 mg/kg/day (not exceeding 1g/24 hours) may be used in severely symptomatic patients.
Dosage Adjustments
- Renal impairment necessitates dose reduction based on creatinine clearance.
Side Effects
Common Side Effects
- Nausea, vomiting, diarrhea
- Numbness or tingling, especially around the mouth
- Headache
- Injection site reactions (pain, redness, swelling)
- Dizziness or light-headedness
Rare but Serious Side Effects
- Nephrotoxicity (kidney damage)
- Hypotension (low blood pressure)
- Cardiac arrhythmias
- Hypocalcemia (low blood calcium)
- Hypokalemia (low blood potassium)
- Hypomagnesemia (low blood magnesium)
- Allergic reactions
- Thrombophlebitis
- Bone marrow suppression
Long-Term Effects
- Renal damage with prolonged use.
Adverse Drug Reactions (ADR)
- Renal failure
- Severe hypocalcemia
- Cardiac arrest
Contraindications
- Anuria (absence of urine formation)
- Severe renal dysfunction
- Active tuberculosis
- Hypersensitivity to disodium edetate or other EDTA drugs.
Drug Interactions
- Digoxin: EDTA can reduce digoxin levels and alter its effects.
- Other chelating agents (DMPS, DMSA, D-Penicillamine): Avoid concurrent use unless medically necessary.
- Anticoagulants: Monitor for altered anticoagulant effects.
- Vitamin and mineral supplements: Avoid concurrent use.
- Insulin: May lower blood glucose and insulin requirements.
- Diuretics: Increased risk of hypokalemia.
- Various drugs (see sources for a comprehensive list)
Pregnancy and Breastfeeding
- Pregnancy Safety Category: C (animal studies inadequate, human risk unknown). Use only if clearly needed.
- Fetal Risks: Potential for fetal harm.
- Breastfeeding: Excretion in breast milk unknown. Avoid if possible.
Drug Profile Summary
- Mechanism of Action: Chelates divalent and trivalent cations.
- Side Effects: Nausea, vomiting, diarrhea, numbness, headache, injection site reactions; rarely: nephrotoxicity, hypotension, arrhythmias, electrolyte imbalances, bone marrow suppression.
- Contraindications: Anuria, severe renal dysfunction, active tuberculosis, hypersensitivity.
- Drug Interactions: Digoxin, other chelating agents, anticoagulants, vitamin/mineral supplements, insulin, diuretics.
- Pregnancy & Breastfeeding: Category C; use with caution if clearly needed; breastfeeding not recommended.
- Dosage: Adults: 50 mg/kg/day up to 3 g/24 hours IV; Children: 40 mg/kg/day up to 70 mg/kg/24 hours IV.
- Monitoring Parameters: Renal function (BUN, creatinine, urinalysis), electrolytes (calcium, magnesium, potassium), blood pressure, ECG, blood and urine lead levels (if applicable).
Popular Combinations
- Dimercaprol (BAL) for severe lead poisoning.
Precautions
- General Precautions: Renal function monitoring, electrolyte monitoring, cardiovascular monitoring.
- Specific Populations: Caution in pregnant women, avoid during breastfeeding, dose adjustments in children and elderly.
- Lifestyle Considerations: No specific lifestyle restrictions.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Disodium edetate?
A: Adults: 50 mg/kg/day up to 3 g/24 hours IV; Children: 40 mg/kg/day up to 70 mg/kg/24 hours IV.
Q2: What are the primary uses of Disodium edetate?
A: Hypercalcemia, digitalis toxicity-induced arrhythmias, lead poisoning.
Q3: How is Disodium edetate administered?
A: Slow intravenous infusion.
Q4: What are the common side effects?
A: Nausea, vomiting, diarrhea, numbness/tingling, headache, injection site reactions.
Q5: What are the serious side effects of Disodium edetate?
A: Nephrotoxicity, hypotension, cardiac arrhythmias, hypocalcemia, hypokalemia, hypomagnesemia.
Q6: What are the contraindications for using Disodium edetate?
A: Anuria, severe renal dysfunction, active tuberculosis, drug hypersensitivity.
Q7: Does Disodium edetate interact with other medications?
A: Yes, significant interactions exist with digoxin, other chelating agents, anticoagulants, and others. Consult a comprehensive drug interaction resource.
Q8: Can Disodium edetate be used during pregnancy or breastfeeding?
A: Pregnancy Category C; use only if clearly needed. Breastfeeding is not recommended.
Q9: What monitoring parameters are essential when administering Disodium edetate?
A: Renal function, electrolytes, blood pressure, ECG.
Q10: What is the mechanism of action of Disodium edetate?
A: Chelation of divalent and trivalent metal ions, facilitating their excretion.
