DOPAMINE HYDROCHLORIDE

Posology Adults:

Use as large a vein as possible for infusion. The initial rate of infusion is 2 to 5 micrograms per kilogram bodyweight per minute and this may be increased gradually by increments of 5 to 10 micrograms/kg/minute until the optimum dose for the individual is achieved.

Up to 50 micrograms/kg/minute may be required, and even higher doses have been used. Paediatric population The safety and efficacy of dopamine hydrochloride therapy in children have not been established.

Method of administration:

For intravenous use The solution must be diluted before administration. 6. A suitable metering device is required in the infusion system to control the rate of flow, and this should be adjusted to the optimum patient response and monitored constantly in the light of the individual patient's response.

Adverse reactions to dopamine are related to its pharmacological action. The following adverse reactions are classified by system organ class and ranked under heading of frequency: Common (>1/100 to <1/10; Uncommon (≥1/1,000 to <1/100).

System Organ Class Frequency Adverse reactions Common HeadacheNervous system disorders Uncommon Piloerection Eye disorders Uncommon Mydriasis Common Ectopic heart beats, tachycardia, anginal pain, palpitation, hypotension, vasoconstriction.

Cardiac disorders Uncommon Aberrant conduction, bradycardia, widened QRS complex, hypertension, gangrene, fatal ventricular arrhythmias have been reported on rare occasions. Respiratory, thoracic and mediastinal disorders Common Dyspnoea Gastrointestinal disorders Common Nausea, vomiting Renal and urinary disorders Uncommon Azotaemia Serious or Life-threatening Reactions: Gangrene of the feet has occurred following doses of 10-14 microgram/kg/min and higher in a few patients with pre-existing vascular disease.

Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Warnings:

Patients who have been treated with MAO inhibitors prior to dopamine should be given reduced doses; the starting dose should be one tenth (1/10th) of the usual dose. Excess administration of potassium-free solutions may result in significant hypokalaemia.

The intravenous administration of these solutions can cause fluid and/or solute overloading resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary oedema.

Precautions:

Hypovolaemia should be corrected where necessary prior to dopamine infusion. Low doses should be used in shock due to acute myocardial infarction. e. a marked decrease in pulse pressure) is observed, the infusion rate should be decreased and the patients observed carefully for further evidence of predominant vasoconstriction activity, unless such an effect is desired.

Patients with a history of peripheral vascular disease should be closely monitored for any changes in colour or temperature of the skin of the extremities. If change of skin colour or temperature occurs and is thought to be the result of compromised circulation to the extremities, the benefits of continued dopamine infusion should be weighed against the risk of possible necrosis.

These changes may be reversed by decreasing the rate or discontinuing the infusion. IV administration of phentolamine mesylate 5-10 mg may reverse the ischaemia. Dopamine hydrochloride in 5% Glucose injection should be infused into a large vein whenever possible to prevent the possibility of infiltration of perivascular tissue adjacent to the infusion site.

Extravasation of dopamine hydrochloride during infusion may cause ischaemic necrosis and sloughing of surrounding tissue. Ischaemia can be reversed by infiltration of the affected area with 10-15 ml of saline containing 5 to 10 mg phentolamine mesylate.

A syringe with a fine hypodermic needle should be used to liberally infiltrate the ischaemic area as soon as extravasation is noted. Administration of dopamine hydrochloride should always be under the direct supervision of a physician to whom facilities are available for monitoring cardiovascular and renal indices, including blood volume, cardiac output, blood pressure, electrocardiography and urine flow.

Glucose solutions should be used with caution in patients with known subclinical or overt diabetes mellitus. When dopamine is used in patients with a history of occlusive vascular disease, particular attention should be paid to the status of blood circulation in the extremities.

The occurrence of undesirable increases in blood pressure or vasoconstriction or decrease in urinary output requires a reduction in dosage of dopamine hydrochloride. The routine use of low-dose dopamine hydrochloride in critically ill patients to prevent or treat acute renal failure is not recommended because this may cause adverse effects which could further compromise such patients.

As the effect of dopamine on impaired renal and hepatic function is not known, close monitoring is advised. Dopamine infusion should be withdrawn gradually, to avoid unnecessary hypotension. Dopamine Hydrochloride 40mg/ml Concentrate for Solution for Infusion contains an antioxidant, sodium metabisulfite, a sulphite that may cause allergic-type reactions including bronchospasm, anaphylaxis and life- threatening episodes in certain susceptible individuals.

The prevalence of sulphite-sensitivity in the general population is unknown and is probably low. Sulphite-sensitivity is seen more frequently in persons with a history of asthma or atopic allergy. This medicine contains less than 1 mmol sodium (23 mg) per ml, that is to say essentially ‘sodium-free’.

1. • Phaeochromocytoma or hyperthyroidism Dopamine should not be used in the presence of uncorrected atrial or ventricular tachyarrhythmias or ventricular fibrillation. Cyclopropane and halogenated hydrocarbon anaesthetics should be avoided.