I have anxiety, taking escitalopram 20mg, since 2 weeks have dull pain and weakness in both thighs..can it be something serious or just anxiety? als?

See your PCP first.: Although anxiety can certainly cause muscle tightness it is seldom felt specifically in the thighs. Escitalopram will help with the anxiety and depression but before you dismiss the pain and weakness as due to anxiety, have your pcp run some tests to exclude other conditions. I would not jump at ALS either.

Anxiety: Pain ; weakness in thighs are musculoskeletal symptoms. At your age, the most likely cause would be activity of sorts. Anxiety itself can present as various physical and/or mental symptoms, including musculoskeletal.(if continues, talk with your pcp) note: anxiety treatment requires twice the medication dose and twice the time to respond to medication treatment compared with depression treatment.