Ever since the introduction of phenolsulphonphthalein as a test for kidney function by Rowntree and Geraghty1 in 1912, sodium hydroxide has been the reagent most frequently employed not only to determine the appearance time of the dye but also, by rendering the urine strongly alkaline, to estimate the percentage excreted in a given length of time.
My object in this communication is to call the attention of the profession to the fact that, although sodium hydroxide undoubtedly is an excellent reagent, it is a potential source of great danger. I would also call attention to two safe and satisfactory substitutes. While not only the dangers of the misuse of sodium hydroxide but also the substitutes for it may be familiar to many, I find on inquiry that there are still those who are not so informed.
The devastating effect of sodium hydroxide on mucous membranes, to which those of the genital and