Hospitals have worked hard to reduce adverse drug events (ADEs) over the past 10 years. Unfortunately such error rates have increased, in part because more prescription drugs are used. (Now 91% of people aged 65+ use prescription drugs, compared to 74% in the early 1990s.) HCUP data (2014) analyzed by the Agency for Healthcare Research and Quality (AHRQ) revealed that ADEs are more likely to be present on admission (more than 2/3 of the ADEs, up 11% from 2011), than to originate during the stay (down 27%). As you might expect, however, in-hospital ADEs can be more costly, have longer length of stay and higher mortality. The most common ADEs involved antibiotics and anti-infectives, systemic agents such as antineoplastic drugs and antiallergy; hormones such as steroids and insulin; and analgesics such as opiates/narcotics. People age 65+ and those in the South had higher rates. AHRQ Statistical Brief #234 published January 2018.