Which allergies can cause swollen lips?

A reaction may include itching, tingling, hives or deeper swelling known as angioedema. The trigger cannot be confirmed from the lip's appearance alone.

Food reactions can begin after eating or after food touches the lips. Medicines may cause swelling soon after a dose or after previous uneventful use. Stings and latex can produce reactions beyond the contact site. Lipstick, balm, sunscreen, toothpaste and flavouring may instead produce contact allergy around the mouth.

Not all reactions use the same immune pathway, and a suspected exposure may be coincidental. Irritant products, trauma, infection and non-allergic medicine effects belong in the clinical assessment too.

Move away from the suspected exposure and remove any product still on the skin without vigorous scrubbing. Do not take another dose of a suspected medicine unless a qualified clinician who knows the situation advises it; some essential medicines require a carefully chosen alternative.

Preserve packaging and ingredient labels, note when swelling began, and record other symptoms such as hives, stomach upset or wheeze. Follow your personalised allergy plan if you have one. Do not use food challenges or patch tests at home to prove a cause.

Get emergency help for breathlessness, wheezing, voice change, tongue or throat swelling, trouble swallowing, collapse, severe dizziness or a rapidly progressing reaction. If prescribed an adrenaline auto-injector, use it according to your emergency plan and do not wait to see whether symptoms settle.

Arrange timely review for a first episode, recurrent swelling, a suspected medicine reaction, or symptoms that persist or worsen. Pain, warmth, pus or fever may point toward infection and also needs assessment.

Ask which exposures are plausible given the timing, what should be avoided meanwhile, and whether your regular medicines need adjustment. Clarify whether testing is useful, how to read ingredient labels, and which symptoms should activate an emergency plan. A precise history is often more useful than a broad list of unverified allergies.