Calcium disodium edetate-chelating agent and its pharmacology

DESCRIPTION:

Edetate calcium disodium is a chelating agent. Because this chelating agent has higher affinity for heavy metal like Pb , Zn , Cd , Mn , Cu and some radioactive metals , that's whys they are capable of removing a heavy metal, such as lead or mercury, from the blood by exchanging with Ca held by it. It is highly ionised , therefore distributed only extracellularly.

PHARMACOKINETICS:

 Rapidly excreted in urine by glomerulus filteration carrying the toxic metals along. It is not     metabolised. Because of its ic nature , calcium sodium edetate is not absorbed from git.It must be   gven parentally. It does not enter brain or CSF.
 Half-life: < 1hour.

 Route of administration: Preferred route is i.v., i.m. injection is painfull.

ADVERSE REACTION:

                   1.Hypotension.

                   2.Cardiac rhythm irregularities.

                   3.Urinary hesitancy.

                   4.Pain, fever.

                   5.Joint pain.

                   6.Headache.

                   7.Tremor.

                   8.Nausea, vomiting.

                   9.Loss of appetite.

                   10.Sneezing.

DRUG INTERACTIONS:

                   1. Steroids + Calcium disodium edetate = Increase Renal toxicity in animals

                   2. Zinc insulin + calcium sodium edetate = Replace zinc.

CONTRAINDICATIONS: 

                   1.Kidney disease.

                   2.Hepatitis.

                   3.Unable to urinate

                   4.Nephropathy

USES:

                  It is used in lead poisining.

REFERENCE:-Tripathi K D"Essential of medical pharmacology",7th edition ,page no-905,906