Hello! Thank you for asking on HCM! I understand your concern and would explain that cialis interacts with both metoporolol and losartan by pharmacological synergism, leading to an increase of their effect on lowering blood pressure. This means that you may be at risk of low blood pressure when taking Cialis while on this antihypertensive therapy. Although, Cialis intake is not contraindicated in this case. It should be used with caution. I recommend to closely monitor your blood pressure during taking Cialis. If your blood pressure doesn t decrease in a noticeable way, there is nothing to worry about it. Hope to have been helpful! Best wishes! Dr. Iliri