Azithromycin and anaphylaxis

Stop taking the medicine and call emergency services if a severe reaction is suspected. If you have a prescribed adrenaline auto-injector, use it as you were trained, then lie down with your legs raised unless breathing is easier sitting up; do not stand or walk.

Anaphylaxis is a rapid allergic reaction that can affect the airway, breathing or circulation. Features can include swelling of the tongue or throat, a hoarse voice, wheezing, struggling to breathe, dizziness, fainting, confusion, or pale and clammy skin. Hives or facial swelling may occur, but a skin rash is not required.

Nausea or diarrhoea alone may be a medicine side effect rather than anaphylaxis. The presence of airway, breathing or circulation problems is what makes the situation an emergency.

Do not take another azithromycin dose until a qualified clinician has assessed what happened. Keep the medicine packaging and note the dose, timing, symptoms and other medicines or foods involved. Ensure azithromycin is entered clearly in your medical and pharmacy records as a suspected allergy until it is evaluated.

After emergency care, arrange follow-up to review whether allergy testing or specialist assessment is appropriate and which antibiotics remain suitable. Do not test the reaction yourself by taking another dose.

Call emergency services now for throat or tongue swelling, noisy or difficult breathing, wheezing with distress, blue or grey lips, sudden faintness, collapse or reduced responsiveness after azithromycin. Use prescribed adrenaline promptly when available; an antihistamine is not a substitute for adrenaline in anaphylaxis.

A new widespread rash, facial swelling or persistent vomiting without breathing or circulation symptoms still needs urgent clinical advice because the reaction may evolve. Emergency observation may be needed even after symptoms improve.

Ask whether the episode fits an immediate drug allergy, what name should appear in your allergy record, and which related antibiotics need caution. Confirm whether you need specialist allergy assessment, an emergency action plan or an adrenaline auto-injector.