Suggest Treatment For Severe Pain In Leg And Difficulty Walking

My mother, Hannah Evangeline Susheela, is not well. She has a severe nerve pain in her leg, and is unable to move. She is not even able to lie down, for that is extremely painful. She has been sitting in her chair in the last few days. The nerve medication, Tegratol 400, which her doctor prescribed her has made her drowsy and weak, and I just learned that it has the potential to affect her blood thinning medication, Warfarin, as well. Her urine was dark brown this morning. Also her urine output was very little. So after speaking to her doctors (GP and Cardiologist) I have decided to stop the nerve medicine for a day or two, until I have a blood test done to determine the thinness of her blood, so that the dosage of her medicine could be adjusted. The GP has also prescribed Renerve Plus injection (1 cc) twice in a week for six weeks. My mother is 81, and I want to know if this prescription meets with your approval. Thank you.