Clinical Study - Ref8P22

Comparative pharmacokinetics of the active ingredient in Maximum Milk Thistle® (Silipide/Siliphos®) and silymarin (standardized milk thistle extract) in rats


1 Inverni della Beffa Research and Development Laboratories, Milan Italy

2 Istituto di Chimica Farmaceutica, Univarea di Milano, Milan, Italy

See National Library of Medicine Citation

The plasma level profile and the biliary excretion of silybin, the main flavanolignan component of silymarin, were evaluated in rats after single equimolar oral doses of the silybin-phosphatidylcholine complex silipide (Laboratory code Idb 1016), (Siliphos®), and of silymarin.

The introduction of this study states that the standardized extract of silymarin is widely used in Europe for the treatment of liver disorders(1-3). It goes on to state the problem with oral use of the main constituent of silymarin (silybin) is the low bioavailability of the compound, as demonstrated in studies with lab animals (4,5) and man (6).

Previous studies in rats (7), healthy volunteers (8) and patients with liver disease (9, 10) have shown that after oral intake of silipide (Siliphos®), plasma silybin levels are several-fold higher than those measured after treatment with silymarin at equal doses in terms of silybin content.

This study showed the relative bioavailability of silipide (Siliphos®) was nearly 10-fold higher than that of silymarin. Measured as silybin, the blood plasma peak for Siliphos® was 1,004, whereas for silymarin it was 139.


  1. Hruby K., Cosmos G., Fuhrmann M., Thaler H. (1983): Chemotherapy of Amanita phalloides poisoning with intravenous silybinin. Human Toxicol.2, 183-195.
  2. Ferenci P., Dragosics B., Frank H., Benda L., Dittrich H., Meryn S. (1985): Randomized controlled trial of silymarin tratment in patinets with cirrhosis of the liver. J. Hepatol., 1, S229.
  3. Ferenci P., Dragosics B., Dittrich H., et al (1989): Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver. J Hepatol.,9, 105-113.
  4. Morazzoni P., Magistretti M.J., Giachetti C., Zanolo G. (1992): Compartive bioavailability of silipide (Siliphos®), a new flavanolignan complex, in rats. Eur. J. Drug Metab. Pharmacokinet., 17, 39-44.
  5. Arcari M., Brambilla A., Brandt A., et al. (1992): Nuovo comlesso di incllusione tra la silybina e la ciclodrestrina: velocita di dissoluzione in vitro e assorbimento in vivo in confronto a fromulazioni tradizianali. Boll. Chim Farmaceutico, 131, 205-209.
  6. Zanolo G., (1989): RBM Exp. N. 254, Inverni della Beffa SpA, data on file.
  7. Morazzoni P., Malandrino S., Pifferi G. (1992) : Comparative bioavailability of a silybin-phosphatidylcholine complex (Siliphos®) and silymarin in rats. In: Bres J., Panis G. (eds).
  8. Barzaghi N., Crema F., Gatti G., Pifferi G., Perucca E. (1990): Pharmakinetic studies on Idb 1016, a silybin-phosphatidylcholine complex (Siliphos®), in healthy human subjects. Eur. J. Drug Metab. Pharmacokinet., 15, 333-338.
  9. Orlando R., Fragasso A., Lampertico M., Marena C. (1990): Silybin kinetics in patients with liver cirrhosis: a comparative study of a silybin-phospatidylcholine complex (Siliphos®) And silymarin. Med. Sci Res. 18, 861-863.
  10. Schandalik R., Gatti G., Perucca E. (1992): Pharmacokinetics in bile following administration of silipide (Siliphos®) and silymarin in cholecystectomy patients. Arzneimittelforsch., 42 (II), 964-968