Table 1. Correlation Between Various Drugs and Gastric Erosion and Ulcers.

NSAIDs: Non-steroidal anti-inflammatory drugs; GI: gastrointestinal

Study	Groups Studied and Intervention	Results and Findings	Conclusions
Study 1: Non-steroidal anti-inflammatory drugs and life-threatening complications of peptic ulceration [52]	235 patients with life-threatening complications due to peptic ulcers were studied to determine how many of them used NSAIDs	60% of patients with bleeding and perforated ulcers were taking NSAIDs, and approximately 80% of ulcer-related deaths occurred in patients who were taking NSAIDs.	There is a strong correlation between patients taking NSAIDs and both the occurrence of peptic ulcers and peptic ulcer-related complications such as bleeding.
Study 2: Effect of potassium chloride supplements on upper gastrointestinal mucosa [53]	225 patients were given various forms of potassium supplementation, and the long-term adverse effects were studied	Among patients who received the potassium supplement with glycopyrrolate, 51% developed erosions and 11% developed ulcers. Among patients who received only the potassium supplement, 33% developed erosion, and 5% developed ulcers.	There is a significantly high correlation between potassium supplementation and erosion of gastric tissue, which can eventually result in ulceration. Some preparations of potassium supplementation may have a larger increase in ulcerative events compared to other preparations.
Study 3: Alendronate, a bisphosphonate, increased upper and lower gastrointestinal bleeding: risk factor analysis from a nationwide population-based study [37]	3,000 patients taking alendronate and 12,000 age and sex-matched controls were compared to determine the rate of GI bleeding, which was typically due to the development of peptic ulcers.	The rate of upper GI bleeding was 2.93% and lower GI bleeding was 2.17% in patients taking alendronate, which is significantly higher than the control group. This was determined after adjusting for potential confounding variables.	The rate of developing both upper and lower GI bleeding is significantly increased in patients taking alendronate compared to a similar population not taking the drug.
Study 4: Doxycycline-induced gastrointestinal injury [48]	There are three case reports of patients having doxycycline-induced gastrointestinal injury leading to erosion.	All three patients had endoscopic and histologic changes consistent with GI injury.	Gastrointestinal injury is a possible adverse effect of taking doxycycline.