Efedrina

Efedrina Medicine

Overdose

a) Symptoms

The symptoms of overdose are normally seen as nausea, vomiting, hypertension, fever, palpitations, tachycardia, restlessness, respiratory depression and convulsions. Paranoid psychosis, delusions and hallucinations may also follow Efedrinae overdosage.

b) Treatment

In severe overdosage, the stomach should be emptied by emesis and lavage. Management is by supportive symptomatic therapy.

Contraindications

Ischaemic heart disease

Hypertension

Thyrotoxicosis

Prostatic hypertrophy

Efedrinae has positive inotropic and chronotropic effects on the heart and its use should be avoided in patients with ischaemic heart disease.

Efedrinae increases blood pressure in man. Over the counter acquisition of sympathomimetics should always be considered in hypertensive patients whose blood pressure control has suddenly deteriorated.

Patients with hyperthyroidism may be susceptible to the effects of Efedrinae. Efedrinae may precipitate acute urinary retention in patients with prostatic hypertrophy.

Incompatibilities

None known

Undesirable effects

The most common side-effects of Efedrinae are tachycardia, anxiety, nausea, restlessness and insomnia. Tremor, dry mouth, impaired circulation to the extremities, hypertension, headache and cardiac arrhythmias may occur. Tolerance with dependence has been reported with prolonged administration.

Myocardial infarction has occurred very rarely in patients taking Efedrinae or pseudoEfedrinae.

Efedrinae may act as stimulant in children with nocturnal enuresis and cause sleeplessness. It may have sedative effects in some children.

The elderly are more sensitive to the cardiovascular effects of Efedrinae.

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. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at www.mhra.gov.uk/yellowcard.

Preclinical safety data

Studies in mice have shown that the lethal toxicity of Efedrinae is increased by elevation of body temperature.

Efedrinae induces acute locomotor stimulatory activity in rats and mice. The estimated lethal dose in children up to 2 years of age is 200mg and for adults 2g. Fatalities are rare and single doses up to 400mg have been given without serious toxic effects.

Therapeutic indications

Efedrinae tablets are indicated for the treatment or prevention of attacks of bronchospasm in asthma.

Pharmacodynamic properties

Efedrinae is a sympathomimetic agent with direct and indirect effects on adrenergic receptors.

When given by mouth in therapeutic doses, Efedrinae constricts the peripheral vessels, thus increasing blood pressure. It also relaxes bronchioles.

Pharmacokinetic properties

Efedrinae is rapidly and completely absorbed after oral administration and extensively distributed throughout the body with accumulation in the liver, lungs, kidneys, spleen and brain.

Peak plasma concentrations are attained during therapy of 65-120 ug/ml, effective bronchodilator plasma levels are in the range 35-80 ug/ml.

The plasma half-life is reported to be between 3-11 hours, with up to 95% being excreted in the urine.

Qualitative and quantitative composition

Ephedrine

Special warnings and precautions for use

Efedrinae should be given with care to patients with hyperthyroidism, diabetes mellitus, angle-closure glaucoma and renal impairment.

Efedrinae has potentially life threatening effects in its acute cardiovascular and central stimulant effects.

Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.

Effects on ability to drive and use machines

Not applicable

Dosage (Posology) and method of administration

Adults

15 - 60mg three times daily

Children

under 1 year

1 - 5 years

6 - 12 years

not recommended

15mg three times daily

30mg three times daily

Elderly

Dosage should be substantially reduced. Initial therapy should be 50% of adult dose.

Special precautions for disposal and other handling

Not applicable