Clinical trial of deglycyrrhizinized liquorice in gastric ulcer.

In the past twenty years evidence has accumulated that liquorice and related compounds accelerate the rate of healing of gastric ulcers. Powdered succus liquiritiae (Revers, 1948) and glycyrrhiza extract (Schulze, Franke, and Keller, 1954; Ferenbach, 1954; Ohrt, 1955) were shown to be beneficial in patients with gastric ulcer but adequately controlled clinical trials of liquorice extracts were not available until 1962 with the result that little attention was paid to this form of treatment. Interest in liquorice as a therapeutic agent was revived with the synthesis of carbenoxolone sodium from glycyrrhizinic acid, a glycoside extracted from liquorice. Carbenoxolone sodium has been shown in a number of controlled clinical trials (Doll, Hill, Hutton, and Underwood, 1962; Doll, 1964; Doll, Hill, and Hutton, 1965; Doll, Langman, and Shawdon, 1968; Horwich and Galloway, 1965; Bank, Marks, Palmer, Groll, and Van Eldick, 1967) to promote the healing of gastric ulcers. However, treatment with either carbenoxolone sodium or succus liquiritiae was often complicated by retention of water and electrolyte imbalance. The frequency and severity of side effects occurring in patients receiving carbenoxolone sodium have been emphasized by many authors (Doll et al, 1962; Turpie and Thomson, 1965; Mohamed, Chapman, and Crooks, 1966). The main side effects noted have included frank oedema, elevation of diastolic blood pressure, hypokalaemia, and paresis of muscles. Langman (1968) stated that a variant of carbenoxolone which is devoid of side effects on fluid and electrolyte balance is clearly needed. Borst, Blomhert, Molhuysen, Gerbrandy, Turner, and de Vries (1950) found that the glycyrrhizinic acid moiety of liquorice was responsible for the fluid retention and electrolyte imbalance. This view was confirmed by Revers (1952). There is now available a preparation of liquorice which does not contain glycyrrhizinic acid; it is found in the proprietary preparation, Caved-(S) Each tablet of Caved-(S) contains: