NSAIDs have long been known to irritate the stomach, hence the advice to take with food or discontinue in case of heartburn / reflux.

However more evidence is mounting that they actually impact the microbiome more seriously and perhaps even permanently.

Additionally, there are emerging data about the negative impact NSAIDs can have on the gut microbiome, which seems to be increasingly important in all manner of surprising ways.

https://med.uottawa.ca/en/news/everyday-drugs-act-surprising-ways-microbiome