Imagine how that number would grow if you could buy it over the counter, just slide it across to the cashier at your local CVS, no prescription or embarrassing conversation with your doctor required. Eva P.P. Bollen, Kris Rutten, Olga A.H. Reneerkens, Harry W.M. Steinbusch and Jos Prickaerts, Beyond Erectile Dysfunction: Understanding PDE5 Activity In The Central Nervous System, Cyclic‐Nucleotide