III. Chemical Properties of Iodeol.—From a study of different specimens of Iodeol, the referee concludes that fresh specimens contain no free iodin and that old ones contain small amounts as a result of decomposition. Iodeol has the solubility characteristics of fats and fat-like compounds. The examination, as a whole, shows that Iodeol contains a peculiar and rather resistant form or combination of iodin. There is nothing in the chemical data that suggests that it could act differently from ordinary iodin compounds, such as iodized fats. It would not act as ordinary iodin.
IV. Pharmacologic Data.—The pharmacologic statements which were submitted were loose and apparently meaningless or misleading. In reply to questions submitted by the referee, the manufacturer finally had some work done and submitted a report by Jean Laumonnier. The referee was unable to confirm some of this work, and as a whole it does not appear materially to elucidate the action of Iodeol. From a consideration of the submitted evidence, and as a result of his own work, the referee concludes that Iodeol does not behave like elementary iodin; it does not coagulate proteins and therefore is not irritant. It is presumably absorbed, but quite probably after chemical change; it is changed into iodid and, like organic iodids, is excreted somewhat more slowly than when inorganic iodids are administered, but the difference does not appear important.
V. Antiseptic and Bactericidal Action.—Elementary iodin is considered a fairly powerful agent in these respects. The activity is presumably due to changes in the proteins, etc., of the bacteria, analogous to the effects which produce pain, irritation and necrosis of the tissue cells. Since the latter effect is not produced by Iodeol, it seems highly improbable, if not impossible, that it should act on bacteria like elementary iodin. It is entirely unjustifiable to credit the known antibacterial qualities of ordinary iodin to “colloid” iodin. This misrepresentation is especially prominent in the circular “Notable New Therapeutic Agents,” as will be seen, for instance, from the following citations:
“Iodine has long been universally recognized as an antiseptic of extraordinary potency. Not only is it rapid and certain in its germ-destroying action, but it also possesses an attribute denied many other antiseptic agents, namely, the power to penetrate and impregnate the tissues. Other antiseptics, as is well known, act on the surface epithelium only.”
“According to Kinnaman (J. A. M. A., Aug. 26, 1905), iodine is far superior to bichloride of mercury, a two per cent. solution killing streptococcus pyogenes in two minutes. Iodine does not coagulate albumin, and is very penetrating.”
The citations imply that this “colloidal iodin” of Iodeol and Iodagol acts as an antiseptic like ordinary iodin, except that it is claimed to be more efficient by “diffusing” more readily. This is entirely unjustified and misleading. If Iodeol and Iodagol are really antiseptic, they must act by some other mechanism than that through which elementary iodin acts, and such antiseptic action would have to be demonstrated by direct observation and not assumed from the known action of free iodin.
Antiseptic and bactericidal effects are easily estimated by laboratory methods. Yet no evidence on this point appeared to have been available until the Council called for this. Laumonnier then carried out some experiments which were in turn submitted to bacteriologic control. The bacteriologist failed to obtain any results with some of the tests, and considered the other data of little value.
The claim that Iodeol and Iodagol have the antiseptic and bactericidal action of free iodin lacks proof and must be considered unwarranted and misleading in the extreme.
VI. Clinical Trials.—The manufacturers and agents of Iodeol presented many letters from physicians; but few, if any, of these gave evidence of careful, critical, controlled observations. They could not, therefore, be considered as acceptable evidence. The more important claims, letters and published papers, however, were submitted to clinical specialists collaborating with the Council, with the request that they examine these and conduct some clinical trials, if they considered it advisable. The results obtained in these preliminary trials did not appear sufficient to warrant further experimentation.