Researchers say it's vital for patients to tell their doctors what over-the-counter (OTC) painkillers they are taking and how often they take them. Though most people who take pain meds such as aspirin and ibuprofen have no adverse effects, their use can cause liver problems or worsen peptic ulcer disease. Experts say arthritis patients who use OTC painkillers are particularly at risk because up to 60 percent of these patients have gastrointestinal side effects related to regular use of the...