Is it safe for me to take imodium while I'm on lexapro (escitalopram)?

Yes. Yes there should be no problem however if the Lexapro (escitalopram) is causing the diarrhea or cramping you may want to re eval your use of lexapro (escitalopram).
Discuss. If these are side effects of Lexapro (escitalopram) discuss them with your prescribing doctor - some side effects of lexapro, (escitalopram) especially early flu-like symptoms, resolve on their own.