Stomach discomfort or pain, nausea, GI intolerance & bleeding, stomach ulcer, activation of peptic ulcer, black tarry stools, rashes or worsening of asthma, liver & kidney problems, headache, dizziness & hearing disturbances; serious skin reactions, some are fatal eg, exfoliative dermatitis, SJS, TEN), severe hypersensitivity reactions, DRESS syndrome, exacerbation of infections in varicella infection, cardiac failure & oedema; haematopoietic disorders.