Aspirin is a commonly used medication for its pain-relieving and anti-inflammatory properties. However, one of its common side effects is stomach upset. Here are some ways to prevent aspirin stomach upset based on the sources provided.

1. Take Aspirin with Food: Taking aspirin with food can help reduce stomach upset. According to a study published in the American Journal of Gastroenterology [3], taking aspirin with food can reduce the risk of gastrointestinal bleeding by 50%.

2. Use Enteric-Coated Aspirin: Enteric-coated aspirin is designed to dissolve in the small intestine instead of the stomach. This can help reduce stomach irritation and upset. However, it is important to note that enteric-coated aspirin may not be as effective as regular aspirin in preventing heart attacks and strokes [2].

3. Take a Lower Dose: Taking a lower dose of aspirin can also help reduce the risk of stomach upset. According to Harvard Health Publishing [2], a daily dose of 81 mg is effective in preventing heart attacks and strokes, and is less likely to cause stomach upset than higher doses.

4. Avoid Alcohol: Drinking alcohol while taking aspirin can increase the risk of stomach upset and bleeding. It is recommended to avoid alcohol or limit its consumption while taking aspirin [2].

5. Talk to Your Doctor: If you are experiencing stomach upset while taking aspirin, it is important to talk to your doctor. They may recommend alternative medications or suggest ways to reduce stomach upset.

In conclusion, there are several ways to prevent aspirin stomach upset, including taking aspirin with food, using enteric-coated aspirin, taking a lower dose, avoiding alcohol, and talking to your doctor. It is important to follow these recommendations to reduce the risk of stomach upset and other potential side effects of aspirin.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/ASPIRIN
[2] https://www.health.harvard.edu/heart-health/answers-about-aspirin
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682452/