<s>[INST] I habitually wear sandals in the spring/summer with a strap between my big toe and second toe (thong type). I woke up Tuesday after wearing/walking in them all day Monday with a swollen big toe/foot and pain upon standing. What could be causing this. I have worn this type of shoe for years. [/INST] Dear patient Acute swelling of big toe without trauma mostly is due to gout. This disease is characterised  by increased levels of serum levels of uric acid and deposition of uric acid crystals in small joints especially of big toe. This needs to be investigated  with serum levels of uric acid from reputed lab nearby you. You need to consult expert orthopaedic surgeon with report. Meanwhile  start tab diclofenac 50mg twice a day for pain relief.  If serum uric acid levels are higher you need to take drugs to lower it. All the best. </s>