Brief Answer: You should undergo further radiologic examinations and laboratory exams. You should be guided by an internal medicine doctor, for a more accurate etiological diagnosis and to adjust your medical therapy . Detailed answer: Thank you for using HCM. First of all, more than a therapeutic approach, I would suggest you to undergo further radiologic examinations, and laboratory exams, in way to detect any possible cause of your high blood pressure. Your symptoms during the high blood pressure episodes, may be suggestive to secondary possible causes of hypertension such as Cushing syndrome , Pheocromocitoma, Hyperaldosteronism, Hyperthyroidism, Sleep apnea, Acromegaly, etc. But for being more precise into guiding you, i would need more anamnestic data and a detailed physical examination. That s why i suggest yo to see an internist who may lead you in detecting the causing factor of your hypertension. In most of the cases in, eventhough you do all tests for secondary causes , it doesn t get out nothing. At this case we are in front of an idiopathic hypertension, which we have to deal with. Regarding to your actual treatment, atenolol is not the first choice, for blood pressure treatment, but as you may have high heart rate, your doctor has chosen it to treat you. It lowers the heart rate, leading to low blood pressure. But as you are still having this attacks even under atenolol, it means that it is not enough for your full treatment. You should make a 24 h ambulatory blood pressure (BP) monitoring . If you have a persistent blood pressure higher than 140/90 mmHg additional blood pressure reduction should be achieved, increasing the atenolol dosage or adding any other drug such as enalapril, lisinopril etc. Atenolol may cause: slow or uneven heartbeats feeling light-headed, fainting feeling short of breath, (when is taken in higher dosage than needed), swelling of your ankles or feet, nausea, stomach pain, low fever, loss of appetite, dark urine, etc. You should avoid drinking alcohol, which could increase drowsiness and dizziness while you are taking atenolol. You should stop smoking as it has seen that the resting and exercise heart rates were significantly greater in smokers than no-smoker patients. Meanwhile, you should do effective lifestyle changes for controlling blood pressure, such as : weight loss , regular physical activity — at least 30 minutes 3 days of the week, eating a diet that is rich in whole grains, fruits, vegetables and low-fat dairy products. You should restrict the salt quantity that you take with food. Try not to get stressed. Hope this is helpful. Let me know if you need more clarifications. Otherwise please close and rate the answer. Kind Regards, Dr. Juarda