Can I drink water or take medication before a nucleic acid test?

In general, drinking a small amount of water before nucleic acid testing usually does not affect the results, and routine medications can be taken as normal. However, excessive water intake or taking certain special medications may interfere with sample collection or the testing process. Here is a detailed explanation:

Nucleic acid testing primarily involves collecting respiratory specimens. Drinking a small amount of plain water will not dilute viral nucleic acids in the specimen nor react with the testing reagents, so there is no need to worry about drinking a small amount of water within half an hour before the test. For patients with chronic conditions such as hypertension or diabetes, it is important to take prescribed medications on schedule, as stopping medication without guidance may pose health risks. These routine medications generally do not affect the accuracy of the test.

However, consuming large amounts of water shortly before the test may cause stomach discomfort and could lead to vomiting when the swab stimulates the throat, thereby interfering with the sample collection process. Additionally, although certain special medications such as antiviral drugs do not directly interfere with test results, individuals are advised to inform the healthcare provider about their medication use beforehand, so that any abnormal results can be properly evaluated in context.

To ensure efficient and accurate nucleic acid testing, it is recommended to avoid drinking large amounts of fluids, eating, or chewing gum within half an hour before the test. During sample collection, cooperate with healthcare staff by tilting your head back and opening your mouth as instructed. After sampling, promptly put your mask back on.