Griseofulvin ultramicrosize

GRISEOFULVIN ULTRAMICROSIZE (Fulvicin P/G, Gris-Peg, Grisactin Ultra)... 

Griseofulvin, a BCS class II drug (Fig. 2), is a well-known example whose poor aqueous solubility causes low and erratic oral bioavailability. As shown below, griseofulvin has a hydrophobic molecular structure, and is practically insoluble in water. Its oral absorption is highly variable, ranging from 25% to 100%, depending on the crystal size. Ultramicrosize griseofulvin preparations were shown to have 100% oral absorption (12). 

Bijanzadeh M, Mahmoudian M, Salehian P, Khazainia T, Eshghi L, Khosravy A. The bioavailability of griseofulvin from microsized and ultramicrosized tablets in nonfasting voluntbefcan J Physiol Pharmacol, 1990 34 157-161. 

Ultramicrosize formulations of griseofulvin are approximately 1.5 times more potent, milligram for milligram, than the microsize preparations. 

Griseofulvin has extremely low aqueous solubility, and material of normal particle size gave rise to poor and erratic absorption. Microsize particles improve absorption, but it is improved even more when it is formulated in ultramicrosize particles as a monomolecular dispersion in polyethylene glycol. 

The absorption of griseofulvin with normal particle size in humans is minimal and unpredictable. However, the absorption can be increased by the costly process of size reduction to microsize or ultramicrosize [56]. 

Pharmacokinetics Oral absorption of griseofulvin depends on the physical state of the drug—ultramicrosize formulations, which have finer crystals or particles, are more effectively absorbed—and is aided by high-fat foods. The drug is distributed to the stratum corneum, where it binds to keratin. Biliary excretion is responsible for its elimination. 

Griseofulvin Fulvicin, Grifulvin, Grisactin 250- and 500-mg microsize tablets 125- to 330-mg ultramicrosize tablets... 

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