Hello! Welcome and thank you for asking on HCM! I passed carefully through your question and would explain that the numbness in your feet could be related to different possible causes: an electrolyte imbalance, peripheral neuropathy, adverse effects related to your current therapy, etc.. I would not recommend taking for a long time codeine, tramadol or diazepam, because they can cause addiction and tolerance, beside other adverse effects. Besides, codeine and tramadol may aggravate IBS. I would just recommend consulting with a neurologist and performing some tests : - complete blood count - blood electrolytes - a nerve conduction study. I would also encourage you to stop taking codeine or tramadol, and see if your symptoms improve. This would implicate these drugs as possibly related to your complaints. Hope you will find this answer helpful! Best wishes, Dr. Iliri