COVID-19 test kits for sale: what to know

A rapid antigen kit looks for viral proteins in a sample, usually collected from the nose. It can give a quick indication of infection, especially when virus levels are higher. A negative result does not always exclude infection, particularly early in illness or when symptoms are absent. A PCR test uses a different laboratory method and may be chosen when a more detailed assessment is needed.

Check the expiry date and instructions before opening the package. Wash your hands, collect the sample exactly as directed, and wait for the stated reading time; do not interpret the strip after that window. Record the date, result, and symptoms. Follow current local advice about staying home and limiting close contact if you test positive, and arrange clinical advice if your symptoms are worsening or you have a higher risk of severe illness.

Seek urgent medical help for severe breathing difficulty, chest pressure, new confusion, difficulty staying awake, or blue, grey, or very pale lips or skin. Contact a clinician promptly for persistent fever, dehydration, or symptoms that are getting worse. A negative home result should not delay care when you feel seriously unwell.

Ask which test suits your symptoms and exposure, whether a repeat or laboratory test is appropriate after a negative result, and which warning signs matter with your medical history.