Studies on Absorption of Eutectic Mixture. I. A Comparison of the Behavior of Eutectic Mixture of Sulfathiazole and that of Ordinary Sulfathiazole in Man.

TLDR

Sulfathiazole can form eutectic mixtures with urea, l‑ascorbic acid, acetamide, nicotinic acid, nicotinamide, and succinimide. The study aims to determine whether the eutectic form can modulate the therapeutic effect of sulfathiazole. The enhanced absorption is attributed to the altered physical state of sulfathiazole in the eutectic mixture, rather than any solubilizing effect of urea. The eutectic mixture produced a microcrystalline suspension in water and exhibited higher oral absorption and excretion compared with ordinary sulfathiazole.

Abstract

1) Sulfathiazole forms eutectic mixtures with urea, l-ascorbic acid, acetamide, nicotinic acid, nicotinamide, or succinimide. It was observed that a eutectic mixture of sulfathiazole and urea produces a microcrystalline suspension of sulfathiazole in water. 2) Sulfathiazole in a eutectic mixture with urea shows higher absorption and excretion after oral administration than ordinary sulfathiazole. 3) Since urea does not possess solubilizing action on sulfathiazole and also it does not enhance absorption of the drug physiologically, the accelerated absorption or excretion must be attributed to the physical state of sulfathiazole in its eutectic mixture with easily soluble compound, such as urea. 4) It is assumed that this new form of preparation will give a means of adjusting therapeutic effect of medical compounds.