Propanolol

My doctor prescribed me 10 mg of this to take twice a day for hypertension and anxiety/sleep. My bp is usually about 130/90. I’ve been taking the 20 mg together before bed because it makes me tired. I do think it makes me a little more relaxed. The only thing I’ve noticed so far is that I get a dry mouth in the night and for a little while in the morning. Is this dangerous to take long term? Dr only gave me a months worth. Do people think it works?