In search of painkillers that don't damage the stomach

Yes, it can. If you take the limit of APAP for a long time, you can have liver toxicity effects. If your liver is healthy though, it will take awhile. However, if you do something that damages the liver at the same time as taking APAP, the effects will be magnified then either on its own. That is one reason you should NEVER take APAP while drinking, or even the day after heavy drinking (i.e. for a hangover).

You can also have magnified effects on your liver depending on other drugs that you might take, or if you have a problem with your CYP1A2 enzyme.

But it’s easy to exceed that as acetaminophen is concealed in quite a few OTC remedies, such as Nyquil. And, “don’t drink a lot” could just be moderate alcohol use, not actual heavy drinking.

Note that use of Probiotics might be able to help with this problem. The seem to help out your gut in many ways.