Severe haemorrhage, risk of bleeding eg, GI ulcer; underlying haemostatis disorders, history of haemorrhagic CVA, undergoing major surgery & using anticoagulants or platelet antiaggregant drugs including low-dose aspirin. Avoid abrupt discontinuation. Patients on controlled Na diet. May affect ability to drive or operate machinery. Renal insufficiency. Not to be used during pregnancy & lactation. Long-term treatment in elderly.