Side effects that may occur while taking this medication include dizziness and upper respiratory tract infections such as a cough, runny or stuffy nose, sore throat dizziness, lightheadedness, blurred vision as your body adjusts to the medication, tiredness, flu symptoms, nausea, or diarrhea. Micardis HCT may cause dehydration. Tell your doctor if you have any symptoms of dehydration including extreme thirst, very dry mouth, muscle cramps or weakness, fast/slow/irregular heartbeat, confusion, or decreased urination. Tell your doctor if you have serious side effects of Micardis HCT including fainting, unusual changes in the amount of urine (not including the normal increase in urine when you first start this drug), toe or joint pain, symptoms of a high potassium blood level (such as muscle weakness, slow or irregular heartbeat), decrease in vision, or eye pain.