There is no such thing as the most effective traditional Chinese medicine that expands blood vessels. The traditional Chinese medicines commonly used in clinical practice that have the effect of expanding blood vessels are Pueraria Mirifica and Yujin. 1. Pueraria Mirifica: sweet, pungent and cool in nature, belonging to the spleen and stomach meridian, it has the function of relieving muscle heat (relieving the heat on the surface of the skin), transmitting rashes and generating fluids, quenching thirst and elevating yang. It is generally used for treating superficial fever, strong pain in the neck and impenetrable measles, feverish thirst, yin deficiency and internal heat, spleen deficiency and heat excretion. 2. Yu Jin: pungent, bitter and cold in nature; it belongs to the liver and gallbladder meridians and has the effects of activating blood circulation and relieving pain (relieving pain by removing blood stasis), promoting qi circulation and relieving depression (relieving stagnation by unclogging qi flow), clearing the heart and cooling the blood, and inducing diuresis in the gallbladder to relieve yellowish coloration (removing evil qi in the biliary tract and eliminating jaundice). It can be used clinically to treat the pain syndrome of qi stagnation and blood stasis (blood stagnation due to unobstructed flow of qi), delirium in febrile illnesses (delirium due to exuberant heat), epilepsy with phlegm closure, vomiting of blood, epistaxis, reversal of menstruation, urination of blood, hemorrhagic dribbling (the appearance of urination of blood accompanied by a painful sensation), jaundice with dampness-heat of the liver and gallbladder, cholelithiasis. The above Chinese medicines have been proved to have vasodilatory effects by modern pharmacological studies, but the clinical use of Chinese medicines should be based on evidence-based treatment under the guidance of Chinese medicine theories, and should not rely on modern pharmacological studies alone. If you have symptoms, you should take medication under the guidance of a professional physician, and do not take medication blindly on your own, in order to avoid delaying the condition or producing adverse reactions.