Are SSRIs effective?

Professor Wayne Drevets examines the efficacy of selective serotonin reuptake inhibitors (SSRIs) in treating depression. Not all patients respond well to SSRIs and may need different treatments.

The efficacy of selective serotonin reuptake inhibitors has been a matter of considerable debate, there are several reasons for that. One reason is because they do have limitations. We usually as psychiatrists have a rule of thumb that one third of people are going to do very well with SSRIs, another third are not going to respond at all to them, and then another third are going to get somewhat better with them. One of the things that I’ve found clinically is a real problem, and this has been variably reported in the literature but not very well characterized yet, is that some individuals who initially respond quite well to SSRIs, the effectiveness will wear off over time. So even though they start out having a great response, over time they will lose their effectiveness. It’s been controversial about whether this class of drugs is more prone to have that wearing-off effect than previous classes like the old tricyclic antidepressants. At any rate, it’s left us in the field with the need to find more effective medications. Another thing that we do in the field is we often end up combining serotonin reuptake inhibitors with antidepressants that have other mechanisms of action. Often by combining antidepressant treatments that have multiple mechanisms of action we can then get people well and keep people well. But often that takes patience on the part of the individuals with depression. They may have to work with a doctor for a couple of years or more to find that combination that’s going to get them well and keep them well.