Rumex crispus L. (curled dock) is commonly used by traditional healers for treatment of various diseases and correction of disorders such as gastrointestinal tract disorders, antihelminthic diseases, anti-inflammatory, and arthritis, and it is also used as laxative, antipyretic, antioxidant, and antimicrobial.
The leaf stalks are used in salads. The root and fruits are used as medicine.
From early to mid spring, young leaves are tasty raw or cooked. If you want to use them raw, the mucilage can be a little overwhelming, so remove the leaf stem (petiole) and use only the actual leaves in salads. Larger petioles may be tough but pleasantly sour. CAUTION: Overdosing Yellow dock leaves can produce Kidney stones due to containing a chemical that can bind with calcium and form crystals that can damage the kidneys. Do not over-eat it. Leaves can be eaten once or twice a week the most for adults.
There is no clinical evidence to support specific dosage recommendations for yellow dock, and caution is warranted because of its oxalate and tannin content. Dosages traditionally used include 2 to 4 tablespoons of the fresh root, or 2 to 4 g of the dry root in a tea 3 times a day for no longer than 8 to 10 days.
The root has been used to ease digestion and improve liver function. Yellow dock has also been used to ease inflammation in the nose and throat.