Is there a best acupressure point to drain phlegm?

There is no such thing as the best acupoint for expelling phlegm, it is too absolute. You can choose Fenglong, Yinlingquan, Sanjiao Yu and other acupoints to expel phlegm.
1. Fenglong: Located on the lateral side of the lower leg, at the midpoint of the line between the calf’s nose point and the tip of the outer ankle. It is an acupoint of the Foot Yangming Stomach Meridian, which has the effect of harmonizing the stomach and strengthening the spleen, resolving phlegm and inducing dampness, and is commonly used in clinics to resolve phlegm.
2. Yinlingquan: Located on the inner side of the lower leg, at the lower edge of the medial condyle of the tibia, in the depression between the posterior edge of the tibia and the gastrocnemius muscle. It is an acupoint of the Spleen Meridian of the Foot Taiyin, which can promote the transportation of the spleen and stomach to facilitate the dispersal of water and dampness (promoting the movement of water to dispel dampness), dispel phlegm-dampness, reduce the production of phlegm, and at the same time promote the elimination of phlegm.
3. San Jiao Yu: located in the lumbar region, 1.5 inches below the spinous process of the first lumbar vertebrae, belonging to the foot solar bladder meridian acupoint, is the back of the San Jiao Yu, San Jiao Yu can dredge and regulate the San Jiao qi, facilitate the flow of waterways, and transform the drink and expel phlegm.
If the patient is not feeling well, it is recommended to go to the hospital as soon as possible, and be diagnosed and treated by a professional doctor, do not blindly press and acupuncture points on your own, so as to avoid further aggravation of the condition. Specific selection of points and operation should be carried out under the guidance of a professional physician.