I was diagnosed with PA 6 years ago and have learned a lot over the years. If your neurologist tells you numbness is all in your mind FIND ANOTHER NEUROLOGIST! I self inject 1 ml B-12 every three weeks. I find that time frame suits me. You can't overdose on B-12 so if you self inject, experiment. If you get injections from a doctor complain and he/she should adjust your dose until you are comfortable. Some helpful hints I've learned: Avoid stress (easier said than done, I know), stress depletes B-12. If you drink alcohol, stop IMMEDIATELY. Alcohol flushes B-12 right out of your system. So does caffiene, switch to decaf ASAP. Do not drink carbonated beverages you will feel much better. Take 400 mcg folic acid every day. B-12 needs folic to stay in your system. I had an MRI that showed spinal damage was already done before I was diagnosed! I can walk but awkwardly and am numb from the waist down. My toes are paralyzed. I must get moderate exercise daily or I could lose the ability to walk. You must be vigilant with this condition. Don't ever allow any doctor to tell you that you are crazy - you are not. This condition is not well understood in the medical community. Find a knowledgable doctor who will treat you with respect.