Benfotiamine, also known as phenylephrine, has a significant vasoconstrictor effect, which can raise blood pressure and treat shock. It is a common prescription drug, commonly used dosage form for injection, the main ingredient is phenylephrine hydrochloride, in clinical practice, it is mainly used for the treatment of shock and anesthesia to maintain blood pressure, control paroxysmal episodes of supraventricular tachycardia; the common adverse reactions of phenylephrine include vertigo, tremor, dyspnea, persistent headache, vomiting, and dizziness and lightheadedness. Phenylephrine is contraindicated in patients with heart block, hypertension, coronary atherosclerosis, hyperthyroidism, diabetes mellitus, and myocardial infarction, and should also be contraindicated in those who have used a glycosaminoglycoside oxidase inhibitor within the last two weeks. Patients should consult a physician before use and follow the doctor’s instructions. If any discomfort occurs during the use of the drug, the drug must be discontinued immediately and medical attention must be sought.