Use of prescription drugs in the United States continues to rise, with slightly more than 4 billion prescriptions filled last year, according to a new analysis.
The 4.02 billion prescriptions dispensed in 2011 is an increase from the 3.99 billion prescriptions dispensed in 2010, according to the analysis, published in the journal ACS Chemical Neuroscience.
Sales of prescription drugs increased as well, from $308.6 billion in 2010, to $319.9 billion in 2011.
The top four money makers in 2011 were: Lipitor, which lowers cholesterol (earning $7.7 billion), Plavix, which prevents blood clots (earning $6.8 billion), Nexium, which treats acid reflux disease (earning $6.2 billion), and Abilify, which treats depression and schizophrenia (earning $5.2 billion.)
Because many people switched from taking brand-name drugs to generic versions in 2011, the top sellers were not necessarily the most commonly prescribed drugs, the analysis says. For instance, Lipitor dropped from the fourth most-prescribed drug in 2010, to the 25th most prescribed drug in 2011 because of loss of its patent protection.
The most commonly prescribed psychiatric medications in 2011 were Xanax, Celexa and Zoloft, which are prescribed for depression and anxiety.
There was a 17 percent increase in sales for ADHD medications, and a 22.5 percent increase in sales for multiple sclerosis treatments, the analysis says.
The analysis was conducted by Craig Lindsley, the editor of ACS Chemical Neuroscience. It was based on information released by IMS Health, a company that provides information, services and technology to the healthcare industry.
Pass it on: There were about 4 billion prescriptions for medications in 2011.
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