Unithiol

(rINN)
Unithiol Chemical formula

💊 Chemical information

DMPS; Unithiolum; Unitiol; Unitioli. Sodium 2,3-dimercaptopropanesulfonate .
Chemical formula: C3H7NaO3S3 = 210.3.
CAS — 4076-02-2.

💊 Profile

Unithiol is a chelator structurally related to dimercaprol. It is water soluble and reported to be less toxic than dimercaprol. Unithiol is used in the treatment of poisoning by heavy metals including arsenic, lead, and inorganic and organic mercury compounds; it has also been used in poisoning with chromium or cadmium, although its efficacy is not established. Unithiol is given orally in doses of 100 mg three or four times daily in chronic poisoning. In acute poisoning, a dose of 1.2 to 2.4 g by mouth, in divided doses over 24 hours, has been suggested. It may also be given parenterally in patients with severe toxicity; a suggested intravenous dose is 3 to 5 mg/kg every 4 hours, reducing the frequency after 1 to 2 days and then changing to oral therapy.
1. Hruby K, Donner A. 2,3-Dimercapto-1-propanesulphonate in heavy metal poisoning. Med Toxicol 1987; 2: 317–23
2. Aposhian HV, et al. Mobilization of heavy metals by newer, therapeutically useful chelating agents. Toxicology 1995; 97: 23–38.

Arsenic poisoning.

Complete recovery, without renal or neurological sequelae, has been reported1,2 following the use of unithiol in patients with potentially lethal acute arsenic poisoning; haemodialysis was also used in 1 patient.2 Increased urinary arsenic excretion, with some improvement in clinical symptoms, has also been reported3,4 with unithiol in chronic arsenic toxicity.
1. Moore DF, et al. Acute arsenic poisoning: absence of polyneuropathy after treatment with 2,3-dimercaptopropanesulphonate (DMPS). J Neurol Neurosurg Psychiatry 1994; 57: 1133–5
2. Kruszewska S, et al. The use of haemodialysis and 2,3 propanesulphonate (DMPS) to manage acute oral poisoning by lethal dose of arsenic trioxide. Int J Occup Med Environ Health 1996; 9: 111–115
3. Wax PM, Thornton CA. Recovery from severe arsenic-induced peripheral neuropathy with 2,3-dimercapto-1-propanesulphonic acid. J Toxicol Clin Toxicol 2000; 38: 777–80
4. Guha Mazumder DN, et al. Randomized placebo-controlled trial of 2,3-dimercapto-1-propanesulfonate (DMPS) in therapy of chronic arsenicosis due to drinking arsenic-contaminated water. J Toxicol Clin Toxicol 2001; 39: 665–74.

Lead poisoning.

Unithiol may be used in lead poisoning, although other chelators are generally preferred. In a study of 12 children1it reduced lead concentrations in blood but did not affect the concentrations of copper or zinc in plasma, although the urinary excretion of lead, copper, and zinc was increased during treatment.
1. Chisolm JJ, Thomas DJ. Use of 2,3-dimercaptopropane-1-sulfonate in treatment of lead poisoning in children. J Pharmacol Exp Ther 1985; 235: 665–9.

Mercury poisoning.

Unithiol is used in poisoning with mercury and mercury salts and has been given by various routes. In 7 patients with poisoning due to mercury vapour or mercuric oxide, unithiol 100 mg given twice daily by mouth for up to 15 days enhanced urinary elimination of mercury;1 the urinary elimination of copper and zinc was also increased in most patients and 2 developed skin rashes. A dose of 5 mg/kg intramuscularly three times daily, reduced to once daily by the third day of treatment, effectively reduced the half-life of mercury in the blood after poisoning with methylmercury.2 A patient with severe mercuric chloride poisoning was treated successfully with unithiol given intravenously for 4 weeks, then orally for 3 weeks.3 Unithiol has also been used with haemofiltration in patients with inorganic mercury poisoning and acute renal failure.4,5
1. Mant TGK. Clinical studies with dimercaptopropane sulphonate in mercury poisoning. Hum Toxicol 1985; 4: 346
2. Clarkson TW, et al. Tests of efficacy of antidotes for removal of methylmercury in human poisoning during the Iraq outbreak. J Pharmacol Exp Ther 1981; 218: 74–83
3. Toet AE, et al. Mercury kinetics in a case of severe mercuric chloride poisoning treated with dimercapto-1-propane sulphonate (DMPS). Hum Exp Toxicol 1994; 13: 11–16
4. Pai P, et al. Treatment of a case of severe mercuric salt overdose with DMPS (dimercapo-1-propane sulphonate [sic]) and continuous haemofiltration. Nephrol Dial Transplant 2000; 15: 1889–90
5. Dargan PI, et al. Case report: severe mercuric sulphate poisoning treated with 2,3-dimercaptopropane-1-sulphonate and haemodiafiltration. Crit Care 2003; 7: R1–R6.

Wilson’s disease.

Unithiol 200 mg twice daily1 was used successfully to maintain cupriuresis in a 13-year-old boy with Wilson’s disease after he developed systemic lupus during treatment with penicillamine and with trientine dihydrochloride. Unithiol was started in 2 similar patients1 but both withdrew from treatment, one because of fever and a fall in leucocyte count after a test dose and the other because of intense nausea and taste impairment.
1. Walshe JM. Unithiol in Wilson’s disease. BMJ 1985; 290: 673–4.

💊 Preparations

Proprietary Preparations

Cz.: Dimaval; Ger.: Dimaval; Mercuval.

💊 Profile

Bordeaux B was formerly used as a colouring agent for medicines and foods but has been replaced by other colours.
Published October 07, 2018.