For a hydrogen breath test, overnight fasting (8â12 hours) is usually required - only water is allowed. Eating a light breakfast a few hours before the test can interfere with accuracy, so itâs best to follow the fasting rule. Certain medicines (like antibiotics, laxatives, or probiotics) can also affect results; ideally antibiotics should be stopped at least 2-4 weeks before the test for reliable readings. Since your antibiotic course ended just last Friday and the test is tomorrow, it may reduce accuracy.
Next Steps
Confirm with the lab or doctor whether to reschedule for more reliable results. For safe guidance, book a consult on Practo to review your medicines and decide timing.