pain
"Took Tramadol for excruciating back pain. Worked marvelously for three weeks, pain 80% decreased, but affected my judgment as I saw events and people in an unrealistically positive way.  After 3 weeks, I started imagining blacks ghosts at night, got depressed and negative, my face felt like sunburned at night, nausea. Needless to say, I stopped taking the drug, withdrawal made the experience worse, I am back with pain waiting for surgery. BAD DRUG!"