Synotia and Synthalin

SYNOTIA (from Greek syn—together, ous, otos—ear), a developmental deformity in which, due to underdevelopment of the lower jaw (see Agnathia), there is a displacement of the ears (external and middle ear) inward and their fusion along the midline of the body between the neck and the upper jaw. SYNTHALIN, decamethylene-diguanidine hydrochloride. A white crystalline powder, easily soluble in water. It was proposed by E. Frank for the therapy of diabetes as a synthetic preparation that replaces insulin and acts when administered per os. However, the hopes that initially arose were not justified. First of all, the mechanism of action of Synthalin is still insufficiently studied. On the one hand, a possible inhibitory effect on the glycolytic function of the liver is possible, but it is associated with toxic phenomena (increased urobilinuria). On the other hand, Straub attributes the action of Synthalin to tissue asphyxia and the strengthening of the anoxybiotic phase of carbohydrate metabolism (according to Warburg), simultaneously, perhaps, with the inhibition of oxybiotic metabolism. We have an analogy in the lowering of blood sugar during suffocation, noted back by Claude Bernard. This view is confirmed by the latest work of Küng, who found a 10-fold increase in the excretion of lactic acid (a product of the anoxybiotic phase) under the influence of Synthalin. Thus, Synthalin is apparently a protoplasmic poison. Its toxicity is quite high: 0.35 mg for a mouse weighing 20 g. Clinical experience notes a decrease in glycosuria and ketonuria. The decrease in blood sugar levels is significantly less than with insulin therapy, and by some authors is not even noted. Synthalin cannot replace insulin, especially in severe cases of diabetes. The initial equivalent of 1.24 g of sugar in the urine, disappearing under the influence of each mg of Synthalin (or the equality: 1 mg of Synthalin = 1 unit of insulin), must, according to de Jong, be reduced to 0.4–0.55 g of glucose per 1 mg of Synthalin. When using Synthalin, quite pronounced dyspeptic phenomena are noted: nausea, vomiting, diarrhea. Along with this, a decrease in blood pressure, lethargy, and sometimes increased thirst and polyuria are noted. These side effects force, according to Priesel and Wagner, the recognition of Synthalin as unsuitable for use in pediatric practice. Dosage for adults is 10–50 mg per day. It is produced in tablets of 10 and 25 mg. It is recommended to take breaks after 2–3 days due to phenomena of accumulation. In Synthalin B (dodecamethylene-diguanidine hydrochloride), released by the same firm Kahlbaum, the toxicity is significantly reduced (but not eliminated). The mechanism of action naturally remained the same. The use of Synthalin is limited to mild cases of diabetes, where it facilitates dietary treatment without itself providing an increase in tolerance (Morawitz).