Can I take a nucleic acid test after taking cough medicine orally?

In general, it is acceptable to undergo nucleic acid testing after taking oral cough medicine, but special circumstances should be noted. Nucleic acid testing specifically detects viral nucleic acid fragments, and cough medications usually do not affect the test results. If in doubt, it is recommended to consult the testing facility or a healthcare provider. The detailed analysis is as follows:

It is safe to undergo nucleic acid testing after taking oral cough medication. Nucleic acid testing detects specific genetic sequences of the SARS-CoV-2 virus by precisely matching primers and probes to the target sequence for diagnosis. The primary function of cough medicines is to relieve respiratory spasms and suppress the cough reflex. Their ingredients typically include antitussives and expectorants, which are unrelated to the structure of viral nucleic acids. These components do not interfere with the binding reaction between primers and viral nucleic acids during testing, nor do they compromise the integrity of the viral nucleic acid. Therefore, they do not affect the accuracy of the test results—neither causing false positives nor false negatives.

When taking cough medication, follow medical advice strictly; do not adjust the dosage or switch medications arbitrarily. Drink plenty of warm water daily to keep the respiratory tract moistened and help thin mucus. Maintain appropriate indoor humidity and good ventilation, avoiding dry air or dust that may irritate the throat. Choose mild, soothing foods and avoid spicy, overly sweet, or salty foods. Ensure adequate rest and avoid overusing your voice to support respiratory recovery.