THYROIDEUM SICCUM 383 



and iodism is less likely to be caused. The ten per cent, solution is 

 for medication per os and the twenty-five per cent, solution is for 

 hypodermic use. 



THYROIDEUM SICCUM — DRIED THYROID GLANDS 



Synonym. Desiccated Thyroid Glands 



This is the dried thyroid glands of animals which are used for 

 food by man, freed from connective tissue and fat and containing 

 not less than 0.17 nor more than 0.23 per cent, of iodine. By spe- 

 cial treatment, thyroiodin and thyroglobulin may be obtained from 

 them. 



Doses. Dog gr. ij — v; 0.12 — 0.3. 



The thyroids of most animals contain iodine, those of man and 

 dogs, more than those of the horse, ox, sheep and pig. Yet these ani- 

 mals are as healthy as others and react as strongly after the removal 

 of the glands. 



Effects of Removal of the Thyroids (Thyroidectomy). If 

 the thyroids are removed from dogs they soon show reflex excitability 

 and occasionally convulsions, and. die within a few days. Thyroid, 

 injected intravenously, a few hours before death will stimulate all the 

 vital functions. In man and monkey, the symptoms develop much 

 more slowly and are characterized by a condition very similar to 

 that of myxedema. 



Action. Thyroids have their principal action upon metabolism, 

 increasing both proteid and fat destruction. The action depends 

 upon the iodine content because the ratio of loss is in proportion to 

 the amount of iodine in the glands. Thyroids which do not contain 

 iodine, do not have this action. There is some controversy as to its 

 action on fat metabolism although thyroid has been in use for a long 

 time in the treatment of obesity. Yet thyroid is not an ideal anti-fat 

 because an ideal treatment for obesity should increase the reduction, 

 of fat without affecting protein waste. The administration of thyroid 

 at any rate causes tissue waste which cannot be stopped by feeding 

 carbohydrates or fat. The augmented protein elimination accounts 

 for about one sixth of the loss of weight according to Dixon, and the 

 rest must be due to destruction of fat and removal of fluid. There 

 is some clinical evidence that thyroid will prpmote the union of frac- 

 tured bones or the growth of bone in normal animals. 



Some investigators have considered that thyroid is but an organic 

 form of iodine because in many cases the reaction depends upon the 

 amount of iodine in the preparation, and may be borne out by the 

 similarity of its effects to those of iodine in some conditions, but thy- 

 roids produce results in myxedema, cretinism or after thyroidectomy, 

 which no other iodine preparation is capable of producing. 



