Just running a quick back of the napkin, because I also think that seems high: The CDC says that there were 117 million adults with chronic conditions in the U

Just running a quick back of the napkin, because I also think that seems high: The CDC says that there were 117 million adults with chronic conditions in the US in 2012 and there are 100 million people over the age of 65, the majority of whom (I'm betting) have at least one prescription. Blood pressure medication, anti inflammatories for arthritis, steroids for skin/muscle/hormonal issues, and on and on. That's your third right there. The issues that come with chronic conditions also tend to be more systemic so their treatments are more likely to have impact on brain chemistry leading to depression. I couldn't find CDC stats for children but I'm willing to bet it'd bring the number of people taking prescriptions for chronic conditions to 125-150 million with all the asthma inhalers, ADHD medication, and so on that adolescents get. Obviously not all of those people are taking a prescription year round and there is significant overlap but I think it's very feasible that two thirds of the country are on at least one prescription between all the chronic and acute conditions. Another thing to consider is that some doctors will write prescriptions for common over the counter medication.