Effects of lipids on bioavailability of sulfisoxazole acetyl, dicumarol, and griseofulvin in rats.

The effects of hexadecane, oleyl alcohol, polysorbate 80, trioctanoin, and triolein on the bioavailability of sulfisoxazole N1-acetyl, dicumarol, and griseofulvin were investigated. Compared to administration of the drugs in water, the rate of absorption of the drugs was either decreased or not changed by the lipids. The extent of absorption of sulfisoxazole acetyl and dicumarol was significantly increased by polysorbate 80 and triolein and not affected by hexadecane or oleyl alcohol. Tricotanoin increased the extent of abosrption of sulfisoxazole acetyl but had no effect on the absorption of dicumarol. Compared to the aqueous vehicle, the extent of absorption of greiseofulvin was decreased by hexadecane, oleyl alcohol, and triolein, increased by polysorbate 80, and not affected by trioctanoin. The extent of absorption of sulfisoxazole acetyl was not affected by the amount of triolein in which it was administered nor by emulsification of triolein prior to administration.