"I am taking acetazolamide and I am feeling a very strange sensation in my knees. It's not permanent, but still quite frequent throughout the day. Is this normal?"

It is not normal to experience a strange sensation in your knees while taking acetazolamide. This medication can have effects on the body's fluid balance, so it may be related to that. It would be best to speak with a pharmacist or a healthcare provider to discuss the possibility of temporarily stopping the medication to see if the situation improves. It is difficult to determine the seriousness of this symptom without further information.