adrenaline tartrate: clinical use

Prescribing considerations

• Ensure the patient and likely caregivers can recognise anaphylaxis and demonstrate correct use of the specific device.
• Advise patients to carry two in-date auto-injectors and to seek emergency medical assistance after every use.
• Use particular caution with cardiovascular disease, arrhythmia, hypertension, hyperthyroidism, phaeochromocytoma, narrow-angle glaucoma, severe renal impairment, urinary retention, diabetes, electrolyte abnormalities, pregnancy and older age.
• Concomitant asthma may increase the risk of severe anaphylaxis. A thick subcutaneous fat layer may delay absorption.
• Characterise likely allergens where possible and provide a personalised emergency plan.

Contraindications and cautions

• There are no absolute contraindications to Jext during an allergic emergency.

Monitoring

• After administration, monitor the airway, breathing, circulation and clinical response in an emergency-care setting.
• Observe for recurrence after initial improvement because biphasic anaphylaxis can occur.
• Consider cardiovascular rhythm, blood pressure, glucose and potassium monitoring according to clinical risk and presentation.
• Report suspected adverse reactions or device faults through the MHRA Yellow Card scheme.

Clinical pharmacology

Adrenaline is a non-selective alpha- and beta-adrenergic agonist. Vasoconstriction supports vascular tone and reduces mucosal oedema; beta-receptor activity promotes bronchodilation and increases cardiac rate and output. It is rapidly metabolised mainly by COMT and MAO, although local vasoconstriction can slow absorption.

Formulation and product differences

• Jext is a brand-specific, spring-activated, single-use pre-filled pen; technique differs from other adrenaline auto-injectors.
• It contains sodium metabisulphite and is essentially sodium-free.
• The solution should be clear, colourless and free from visible particles.
• The cartridge seals and plunger components are latex-free, and the supplied carry case protects the device during storage and transport.

Injection

Route: Parenteral

Strengths: 150 micrograms, 300 micrograms, 1 mg/10 mL