Hi, It is not safe to take viagra while on anti-hypertensive medications. If Viagra is taken along with anti-hypertensive medicines like diovan, metoprolol, and clonidine, it can add to the blood pressure-lowering effects of these medications. You must contact your doctor immediately if you experience signs and symptoms of low blood pressure such as dizziness, light-headedness, fainting, flushing, headache, or a rapid pulse or heart rate. You may be more likely to experience these problems at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Dapoxetine does not cause such interaction when taken along with these anti-hypertensive medications. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Mohammed Taher Ali, General & Family Physician