Cough
"Googled &quot;dextromethorphan &amp; diarrhea&quot; and it lead me here.  Is it helping my cough? I doubt it.   It&#039;s hard to imagine things being worse in the constant coughing department but I guess the only way to know is to stop taking it (which I plan to do).  The bigger problem is the loose stool.  As someone who lives with constipation on a daily basis, this side effect was quite surprising.   I feel bad for any &quot;regular&quot; people out there as you must be truly suffering rather nasty outcomes from unintentionally taking a laxative."