Does holding metronidazole in the mouth affect nucleic acid testing?

Under normal circumstances, holding metronidazole in the mouth does not affect nucleic acid testing. However, if infection-related symptoms occur before testing, careful evaluation is necessary. The detailed analysis is as follows:

Nucleic acid testing identifies unique genetic sequences of the novel coronavirus using specific primers, enabling highly targeted detection of infection. Metronidazole is an antibiotic effective against anaerobic bacteria. When held in the mouth, it acts primarily at the local oral site. Its components do not interact with viral nucleic acids, interfere with the binding of primers to viral genetic material during testing, or alter the structural characteristics of the viral nucleic acid. Therefore, it does not cause false-positive or false-negative results, and there is no need to discontinue its use specifically before testing.

Metronidazole should be used orally only as prescribed by a physician, with strict adherence to recommended dosage and duration—do not arbitrarily increase or decrease the dose or extend usage time. Maintain good oral hygiene in daily life and rinse your mouth after meals to prevent bacterial growth from food residues. Before undergoing nucleic acid testing, a simple mouth rinse may be performed to remove residual medication, but excessive cleaning is unnecessary. Avoid spicy and irritating foods in your diet to minimize irritation to the oral mucosa. Drink plenty of warm water and maintain regular sleep patterns to support recovery.