According to a study published in the journal The Lancet, the risk of stomach bleeding caused by long-term aspirin use can be decreased with a brief course of antibiotics. Aspirin is known as a useful preventative drug in low doses for people at high risk of strokes or heart attacks; however, on rare occasions, it can provoke internal ulcer bleeding.

Earlier, the findings of the HEAT (Helicobacter pylori Eradication Aspirin) trial led by Dr. (Prof.) Chris Hawkey from the University of Nottingham revealed that aspirin can cause ulcers in the stomach caused by a particular type of bacteria, Helicobacter pylori, to bleed by thinning the blood.

On the other hand, the findings of the recent "STAR" (Simple Trials for Academic Research) trial showed that ulcer bleeding can be significantly reduced following a one-week course of antibiotics. In the study, more than 30,000 patients were enrolled and randomly assigned to receive antibiotics or placebos. These participants were followed for up to 7 years.

The study results showed that over the first two and a half years, only 6% of the participants who received antibiotic treatment were admitted to the hospital because of ulcer bleeding, in comparison to 17% of the patients who received dummy tablets. Similarly, in the group that received the dummy drug, the first hospitalization for ulcer bleeding occurred after 6 days in comparison to 525 days following antibiotic treatment. 

(Source: https://www.tribuneindia.com/news/health/study-finds-how-regular-aspirin-use-can-cause-stomach-bleeding-448021 )