By the way, that might sound bad (Lexapro suppressing or altering immune function), but for reasons that are not yet fully understood, drugs like Lexapro tend to correct or alter immune system differences that have been shown to be correlated with depression, anxiety, etc. We don’t know exactly why this is yet but we do know that serotonin is an important chemical for mood regulation and it’s also somehow involved with the immune system. It could even be the case that depression and anxiety disorders arise out of an immune system difference and medications help to fix this difference—some evidence points in that direction. But in case it sounds scary to anyone that Lexapro can change your immune system function, it’s better to think about it as “people with mental health issues might have different immune systems and for whatever reason this helps change that to help with mood/behavior.” We have a lot to learn about it but I’m just saying don’t quit your antidepressant because you hear it can affect your immune system, focus on if the Lexapro is working well to treat what it’s meant to treat

Doctor says it’s not related? Your doctor is wrong. Lexapro, like many antidepressants or other SSRIs, slightly suppressed the immune system. We’re still figuring out exactly why this is but lots of evidence points to menta health issues like major depressive disorder correlating to immune system abnormalities that, surprisingly, antidepressants may help correct or modify. What we do know is that Lexapro slightly suppresses the immune system (remember your doctor has decided that the benefits of this medication outweigh risks for you). When you have the herpes virus that causes cold sores, it’s your immune system keeping that virus dormant and thus you don’t have active cold sores outbreaks. When your immune system is not performing at its best, like when you have a cold, are very run down and stressed, not getting enough sleep, if you drink too much alcohol, or *when taking a drug that suppresses the immune system*, it isn’t able to keep the virus dormant and keep active outbreaks at bay. So you might be a bit more likely to have outbreaks on Lexapro, though we need more studies on this specific phenomenon the mechanism that would make this happen is evidence based (Lexapro is known to suppress immune system, suppressed immunity is known to lead to cold sore outbreaks). It isn’t likely to make a major difference any more than not getting enough sleep or otherwise being crappy to your body would do, but it’s definitely possible. I’m experiencing an increased rate of outbreaks after starting Lexapro too. My anecdote doesn’t mean much but I’ve taken a number of meds that suppress the immune system and doctors always told me that yes, that might be linked to seeing more cold sore outbreaks, and Lexapro is no different here. I will be taking more valtrex and lysine with my doctor’s OK to help combat this, as the Lexapro is definitely helping me! Good luck.

Lexapro cause acne too? DD had cold sores and now acne

Has anyone found a scientific reason for this? I.e., what chemical component of the drug would result in this reaction?

Me too, been on Lexapro for 1 month and have had one cold sore on top of another for the last week.