Have you ever been in a bad mood, had difficulty remembering things, or had trouble falling asleep and there is no good reason why? Well, it might be an uncommon side effect of one of the medications you are taking. Whether prescription or generic, some commonly prescribed drugs can cause at least 10,000 patients – with some more than 100,000 – to experience mental side effects each year. Check out the chart in the link to the article below to see the effects of Zithromax, Propecia, Norvasc, Singulair, Advair Diskus Inhaler, Lanoxin, Nexium, Zocor/Lipitor/Crestor, and Lopressor.