<s>[INST] is sodium monofluorophosphate toxic (found in toothpaste) I realize by conventional standards there may be considered a low-toxicity rate but I have heard even small amounts may cause neurotoxicity. People do use toothpaste every day and often multiple times per day. [/INST] Hello,Let me tell you that like other drugs sodium monofluoro-phosphate  has some side effects and your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Sodium monofluoro-phosphate can cause gum irritation but it does not cause neurotoxicity.Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Prabhash Verma, General & Family Physician </s>