Yeah, I got it, too, but I didn't feel it in the jaw, I felt it as clogged ears. Kept going to see if they were filled with wax. An ENT man told me it was most likely jaw clenching from the Lexapro.
Jaw Clenching could also be from your anxiety? I'm a grinder when I'm anxious. Maybe your Lexapro isnt working for you? How do you feel otherwise?
I have been taking 30 mgs of lexipro for 4 months with out a problem. Jaw clenching can start with bi-polar medications and sometimes it is permanent.
I would ask the doctor for another med and tell him about the jaw clenching.It could be permanent! It could be the result of another medication. See drugs.com for side effects that list items that even the doctors do not know about. This happened wit me when I was given Depikote. My wife had to help me walk down hill. I checked Drugs.com ind it indicated this problem. I told the doctor but she did not believe me but said to get off of it. I did and the symptoms disappeared.
I would wake up with an aching jaw and have to like "exercise" my exhausted jaw upon waking. Honestly I still have it. It's been over a year BUT it is less severe. I'm on 10 mg and I take it at night as it makes me really really sleep (oddly Klonopin doesn't!!).
It will lessen but hopefully for you it will go away. I suppose there are worse side effects out there, right? =)
Good luck!!!!
Katrina