Jext is a pre-filled auto-injector containing adrenaline (epinephrine), used for the emergency treatment of severe allergic reactions (anaphylaxis). Anaphylaxis can occur rapidly after exposure to allergens such as certain foods, insect stings, medicines, or latex, and may cause symptoms like swelling, difficulty breathing, a rapid drop in blood pressure, or collapse.

Jext works by quickly narrowing blood vessels, relaxing airway muscles, and reducing swelling, helping to stabilise the condition until medical help is available. The device is designed for easy self-administration into the outer thigh, even through clothing. After use, emergency medical attention should be sought immediately.