This information is intended for use by health professionals
|Arachis oil (peanut oil)||(1595.00 mg/2 ml)|
|Benzyl benzoate||(200.00 mg/2 ml)|
Adults400 - 800 mg, in divided doses, on the first day.200 - 400 mg, in divided doses, on the second and third days.100 - 200 mg, in divided doses, on the subsequent days.Within the above dose range, individual dosage should be calculated on a bodyweight basis and will depend upon the severity of symptoms and the causative agent. As a general guide, single doses should not exceed 3 mg per kg bodyweight. However, in severe acute poisoning, single doses up to 5 mg per kg bodyweight may be required initially.Paediatric populationDimercaprol Injection is well tolerated by children and the dosage should be calculated on the basis of bodyweight, using the same unit dose per kg of bodyweight as for an adult under similar clinical circumstances.
ElderlyThere are no specific data on the use of dimercaprol in the elderly but since it is eliminated via the kidney, it should be used with caution in this age group.
Method of administrationFor intramuscular injection.
Blood and lymphatic system disordersHaemolysis, transient reductions in leukocyte count have also been reported (see section 4.4).
Psychiatric disordersAnxiety, restlessness
Nervous system disordersHeadache, tingling of the hands and other extremities, tremor. High doses have produced hypertensive encephalopathy with convulsions and coma.
Eye disordersBurning sensation of the eyes, lacrimation, conjunctivitis, blepharospasm
Cardiac disordersElevation of blood pressure accompanied by tachycardia
Respiratory, thoracic and mediastinal disordersRhinorrhoea, a feeling of constriction in the chest and throat
Gastrointestinal disordersNausea and possibly vomiting, salivation, abdominal pain, burning sensation of the lips, mouth and throatHepatobiliary disordersHepatotoxicity/liver injury
Skin and subcutaneous tissue disordersSweating of the forehead and hands
Musculoskeletal and connective tissue disordersMuscle pain and spasm, pain in jaw
Renal and urinary disordersRenal impairment
Reproductive system and breast disordersBurning sensation in the penis
General disorders and administration site conditionsLocal pain may occur at the site of injection and gluteal abscess has occasionally been encountered. Pyrexia.
InvestigationsActivated partial thromboplastin time prolonged, blood zinc decreasedPaediatric populationA side effect apparently peculiar to children is a fever which develops after the second or third injection, and persists until treatment with dimercaprol is terminated.
Reporting of suspected adverse reactionsReporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme (website: www.mhra.gov.uk/yellowcard).
SymptomsSymptoms of over dosage include malaise, nausea, vomiting, lacrimation and salivation, burning sensation of lips, mouth, throat and eyes with headache. A sense of constriction of the throat and chest. Increased blood pressure maximal after 15-20 minutes. Transient effects lasting about four hours.
ManagementTreatment consists of the subcutaneous administration of diphenhydramine 50 mg or ephedrine 30 mg or ephedrine in a dosage of 30-60 mg orally if time permits.
Mechanism of actionThe sulphydryl groups of dimercaprol compete with endogenous sulphydryl groups on proteins such as enzymes to combine with these metals; chelation by dimercaprol therefore prevents or reverses any inhibition of the sulphydryl enzymes by the metal and the dimercaprol-metal complex formed is readily excreted by the kidney.
AbsorptionAfter intramuscular injection, maximum plasma concentrations of dimercaprol may be attained within one hour.
DistributionDimercaprol is widely distributed to all body tissues, with the highest concentrations found in the kidneys and liver.
BiotransformationDimercaprol is rapidly metabolised and the metabolites and dimercaprol-metal chelates are excreted in the urine and bile.
EliminationElimination is essentially complete within four hours of a single dose.