The hazards of taking Phentolamine Mesylate Tablet on a regular basis include nasal congestion, itching, gastrointestinal symptoms, cardiac muscle, low blood pressure and so on. 1. Long-term consumption of phentolamine mesylate tablets can appear nasal congestion, itching, headache and other adverse reactions, may also appear flushing, urinary tract infection, fatigue, etc.; the drug can make the digestive tract smooth muscle excitation, causing abdominal pain, diarrhea, nausea, vomiting, etc., but also may induce ulcer disease; a small number of people can appear palpitations, accelerated heart rate, hypotension, etc., and a very small number of individuals will appear upright hypotension. 2. Phentolamine mesylate tablets should be contraindicated in patients with severe arteriosclerosis, angina pectoris, myocardial infarction, hepatic and renal insufficiency, and gastric ulcers; and should be used with caution in psychiatric patients and diabetic patients. It is recommended to use Phentolamine Mesylate Tablets under the guidance of a doctor, and not blindly use the drug on your own.