Yes — your cat can still take a PCR test while on antibiotics.
PCR tests detect the DNA of bacteria, parasites, or viruses, not live organisms, so antibiotics do not stop the test from working. However, antibiotics can sometimes lower the amount of detectable DNA, which may slightly reduce the chance of identifying certain infections.
What we recommend:
- If your cat is currently sick or still showing symptoms, it’s reasonable to test while on antibiotics.
- If antibiotics were just started and your cat is improving, you may choose to wait 3–5 days after finishing antibiotics for the most accurate results.
If you’re unsure which timing is best, our team is always happy to help you decide based on your cat’s symptoms and treatment history.
Jan 30, 2026