The irritant action of some drugs derived from hydnocarpus oil

ABSTRACT

1- An acid value of 3 is sufficient to render hydnocarpus preparations irritant. 2- Hemolysis is caused rapidly by salts of hydnocarpus acids in normal saline but it is so far inhibited by the presence of serum that it cannot be considered an important factor in causing pain on injection. 3- The amount of formic acid present in ethyl esters which have deteriorated is insufficient to account for more than a small part of the irritation. 4- Aralkyl esters (thymyl-, phenylethyl-, cinnamyl-, and menthyl-) of the crystalline acids are less irritant than the ethyl esters, causing no necrosis on intradermal injection. 5- Iodized ethyl esters of the crystalline acids are unstable on exposure to air, but oxidation is inhibited by addition of 0.1 percent of catechol or pyrogallol.