PSA: different medications come in different dosages. In other words, for example, 20mg (or 100mg) is not the standard dosage for all medications, even within the same class. I sometimes talk with patients who worry they are being over medicated when they switch from one antidepressant to another. However, the dosages are often different; for example, fluoxetine may start at 20mg while bupropion may start at 150mg. It’s not apples to apples.