Yes, I used to have the same side effects as you are experiencing now. I noticed the effects increased the longer I used the product. Especially feeling lethargic. I had no other choice but to find a way to minimize my usage. Obviously side effects are user specific and one needs to listen to what their body is telling them. I've copied a post of mine below regarding the use of Immodium with a different twist in case you find it useful. Here's to figuring it out so you can begin to feel better!
You are talking to a former Immodium addict. I'll try to save you lots of time and frustration by chiming in with my two cents...since you put it out there to us
I used to take Immodium to compensate for my poor eating choices when I was out socially. As Sand stated, some of the time it worked but once your gut is aggravated there is no amount of Immodium that can stop you from getting sick. Honestly, looking back in time I now see that I took Immodium to avoid me truly dealing with my IBS head on. I wasn't willing to admit that my gut could no longer tolerate the food things that gave me pleasure for so long. My intuition told me that it was time to take this condition seriously and put some work into the necessary changes that needed to take place, BUT I didn't want to do the work to make it so. In many ways I was acting childish when what my IBS was needing me to do was to grow up and take charge of my life.
Three years later, I am IBS stable. I have completely evolved as a human being in the way I handle stress and the acceptance of "what is" (I have IBS), and the food choices I make. My overall health has improved since most of the foods I needed to eliminate were toxic to my body to begin with. Little did I know that my IBS was a blessing in disguise.
All this to say, is this, keep the Immodium in your purse just in case. Go out socially but choose wholesome choices when you're there and just in case there aren't any (till you become stable) eat something IBS safe before you go or take a little something with you that is. I still keep the Immodium in my purse but haven't used it in over 2 years now all because I've learned the truth about how to be with my IBS condition. Your IBS condition is calling you forth to take action with it. Immodium puts off the inevitable to a later time. I know you can do this! Please feel free to write me if you want to talk further. Keep smiling, things will get better!