Is it normal for me to experience involuntary movements while taking a combination of cough syrup and Wellbutrin?

Yes, it is possible that you are experiencing involuntary movements due to an interaction between the cough syrup and your medication. It is important to avoid taking cough syrup with dextromethorphan when using antidepressants like Wellbutrin. It would be best to consult with a pharmacist to find a cough syrup that is safe to take with your medications. Additionally, it would have been preferable not to take Sublinox, as it passes through the same metabolic pathway as the other medications mentioned.