What does it mean if the blood vessels under the tongue are thick and dark?

The presence of thick and dark blood vessels under the tongue may be caused by various factors. Normally, the venous vessels beneath the tongue may appear relatively thick and somewhat dark in color, which is usually a normal phenomenon and not a cause for excessive concern. However, if the sublingual blood vessels are abnormally thick and dark, this could be associated with conditions such as sublingual varices, sublingual gland cysts, or hypertension, all of which may affect normal vascular function. For mild symptoms, adjusting the diet—such as increasing intake of light foods and avoiding spicy or irritating foods—may help alleviate the condition. If symptoms are more severe, prompt medical consultation is recommended. A doctor may prescribe appropriate medications based on the diagnosis, such as Compound Danshen Dripping Pills or Xuefu Zhuyu Pills. In extreme cases, such as severe sublingual varices, surgical intervention may be required to resolve the issue. Additionally, maintaining healthy lifestyle habits—such as avoiding excessive fatigue and practicing good oral hygiene—can also help prevent and improve the condition of thick and dark sublingual blood vessels.