NSW Health advise:
If you’re taking a saliva rapid antigen test, do not eat, drink or brush your teeth for at least 30 minutes before putting the swab in your mouth.
Rapid antigen tests can be very accurate when used as instructed. However, food and drink can impact the accuracy of the result.
If testing before going to school or work, we recommend taking a test first thing in the morning, before eating, drinking or brushing your teeth.
