498 EMIL GOETSCH 



Therapeutic Test with Iodine and Thyroid Extract 



It is a well known fact that the administration of iodids over long 

 periods to cases of goiter may produce symptoms of hyperthyroidism 

 (Kocher). Fr. von Mueller suggested the use of iodin in small amounts 

 for the purpose of disclosing hyperthyroidism, for in those suffering 

 from the latter there is often an intolerance to iodin which produces 

 emaciation and tachycardia after its administration. Thyroid extract 

 has also been used as a therapeutic test to disclose a latent or incipient 

 hyperthyroidism. Graded doses of thyroid extract are taken at four-hour 

 intervals daily for three or four days or less if the characteristic symp- 

 toms of hyperthyroidism are produced earlier. The pulse rate is taken 

 in the morning, afternoon and evening before thyroid feeding is begun 

 and daily thereafter until symptoms are produced. After the adminis- 

 tration of small amounts of thyroid extract in cases of hyperthyroidism 

 symptoms and signs are brought out, such as irritability, twitchings, 

 dyspnea, nervous manifestations, increased pulse rate, perspiration and 

 tremor, these symptoms being produced earlier and on smaller doses of 

 thyroid extract than in normal individuals or, more particularly, in those 

 with hypothyroidism. 



In the latter instance relatively large doses can be given over a con- 

 siderable period without producing symptoms of hyperthyroidism. In 

 cases of hyperthyroidism the pulse rate often does not return to normal 

 even after the cessation of thyroid administration. In fact, it may con- 

 tinue to be rapid and irregular for several days. 



There is an element of danger in the administration of iodids, iodin 

 or thyroid gland extract to show a latent hyperthyroidism. The dura- 

 tion of the test is too long, it requires the patient to be in bed for two, 

 three or more days; it is associated with a considerable period of dis- 

 comfort, and in the end the results are not clear-cut and precise and, 

 therefore, not particularly diagnostic. These tests cannot be applied in 

 a routine clinical way. 



Epinephrin Mydriasis Test of Loewi 



Loewi found that in pancreatectomized animals, in human diabetics 

 and in cases of hyperthyroidism the instillation of a few drops of 1 to 

 1000 solution of cpinephrin produced dilatation of the pupils. He be- 

 lieved that the internal secretions of the thyroid and suprarenal glands 

 are syneraistic and that both act by stimulating the sympathetic nervous 

 system. In cases of hyperthyroidism the sympathetic nerves should there- 

 fore be in a state of irritability. As a result the dilator fibers of the 



