Gout

The pain arrives suddenly — and it is brutal. A joint, often the big toe, swells up, turns red, hot, hypersensitive. Even the touch of a bed sheet can be unbearable. What is happening medically: uric acid crystals deposit in the joints, and the immune system responds with a massive inflammation. The body is attacking something it produced itself.

That is the key: the attack comes from within. The crystals are not a foreign body — they are a waste product of your own metabolism, accumulated over a long period of time because they were not excreted. Something has backed up. Something that should have moved on has stayed. And at some point the system tips over.