But it is best to drink jujube longan and medlar water on an empty stomach. Jujube has the functions of invigorating spleen and stomach, invigorating qi and nourishing blood, and enhancing immunity. Longan is warm and sweet, which benefits the heart and spleen and qi and blood; It has a good nourishing effect. Can be used for insomnia, forgetfulness, fright, dizziness and other symptoms caused by deficiency of both heart and spleen and deficiency of qi and blood. It can also treat weakness or mental decline after illness, and it is easier to be absorbed by drinking on an empty stomach.