muscle spasm
"Felt like a fart but it was a shart. Saw double, can't sleep, loss appetite , dizzy, chest pains my chest felt heavy, it did make my head forget about the pain but it was still there. Bilateral spinal muscles where in spasm. T12 L1 and 2. problem. Never took this drug ever and wont ever again. Nauseated diarrhea bile colored. I took half the pill .  It is nothing like motrin. Flexaril is a safer medication less likely to shart your pants.  But took what was prescribed never heard of this drug before."