Side effects of the measles vaccine

The measles vaccine trains immune memory without causing measles infection. Tenderness, redness or swelling where the injection was given may appear first. A mild fever, feeling tired, or a small rash can occur later, and some people notice swollen glands. These reactions usually settle without specific treatment. A fever after vaccination is a recognised response, but fever can also have another cause. The vaccine does not give someone measles; a new widespread rash with significant illness should still be assessed.

Rest, drink fluids and keep the injection site comfortable. Wear light clothing if you feel feverish and follow the product or clinician advice about symptom relief. Record when symptoms began and whether they are improving. Keep the vaccination record available, especially if another dose or a combined MMR vaccination is planned. Do not give a child medicine unless the dose is suitable for their age and a healthcare professional or product instructions support it.

Call emergency services for trouble breathing, swelling of the face or throat, collapse, or widespread hives soon after vaccination. Arrange prompt medical advice for a high or persistent fever, unusual sleepiness, dehydration, a seizure, or a rash with a child who appears very unwell. A GP consultation can help distinguish a routine reaction from an infection or another problem.

Ask which reactions are expected for the vaccine given, how to manage fever or discomfort, when a further dose is due, and whether allergies, pregnancy, immune problems or recent medicines change the vaccination plan.