Americans shelled out $320 billion on medicines in 2011, according to a report issued by the IMS Institute for Healthcare Informatics. That's up 3.7 percent from $307 billion in 2010. The report cites newly available generic treatments for many chronic conditions as a factor in keeping the spending increase minimal. However, while the past decade saw the most medicines launched in a 10-year period brought new treatment options to more than 20 million Americans, patients visited their physicians and used prescription drugs less often, the report states.