<s>[INST] Hi, My friend is having surgery Wednesday to fix a problem between L3 and L4. The doctor said this was the only solution. My question they did not tell her discontinue any medications that she is on sucn as asprin etc? I am having a knee replacement on the July 16th and I had to get off all my medication 2 weeks prior to that date? What would be the difference?? Thank you. [/INST] Hello, Welcome, and thanks for sharing your concern I went through your query, and I feel, you are intelligent that you noted this fact, if your friend is on aspirin or any other blood thinning agents, than stopping them before surgery is a must, spine surgery is even more dangerous than the simple replacement surgery, so ask her to talk to her doctor regarding this concern, and follow the advice given. I hope my advice would have been useful, in decision-making regarding your treatment, still if you have any clarifications or doubts feel free to contact back. Thanks. </s>