Pharmacokinetics of silybin following oral administration of silipide in patients with extrahepatic biliary obstruction.

The pharmacokinetics of silybin, the main active component of silymarin, following administration of a lipophilic silybin-phosphatidylcholine complex (silipide) was evaluated in fourteen patients with cholestasis secondary to biliary extrahepatic obstruction. Each patient received a single oral dose of silipide (120 mg, expressed as silybin equivalents). Blood samples for high performance liquid chromatography (HPLC) determination of free (unconjugated) and total (free+conjugated) silybin were collected at frequent intervals for up to 24 h after dosing. Absorption from the gastrointestinal tract occurred rapidly, peak concentrations of free drug being observed within 3 h in most patients. Thereafter, the decline in plasma free silybin levels was relatively rapid, and at 12 h the concentration of free drug had already approached the limit of quantitation (2 ng/ml). At all sampling times, the total (free+conjugated) concentration was much higher than the free concentration. Total silybin levels reached a peak at about 3 to 4 h and persisted at relatively high values (> or = 400 ng/ml) throughout the entire sampling period. On average, the area under the curve for total silybin was more than 40-fold greater than the area under the curve for free silybin. These data suggest that extrahepatic biliary obstruction is associated with a reduced clearance of conjugated silybin, probably due to impaired excretion of the conjugate in bile

Pharmacokinetics of silybin in bile following administration of silipide and silymarin in cholecystectomy patients.

The biliary excretion of silybin, the main active component of silymarin, was evaluated by using a specific HPLC method in 9 cholecystectomy patients with T-tube drainage following single oral doses of silipide (CAS 134499-06-2), a lipophilic silybin-phosphatidylcholine complex (IdB 1016), and of silymarin (120 mg, expressed as silybin equivalents). After intake of silipide, the concentration of silybin in bile reached a peak within 4 h and declined thereafter with a mean time of about 10 h. After administration of silymarin, biliary silybin concentrations were several-fold lower than those observed after intake of silipide. The bile collected after silymarin intake also contained considerable amounts of isosilybin (a silybin isomer) and very low levels of silydianin and silycristin. The amount of silybin recovered in bile in free and conjugated form within 48 h accounted for 11% of the dose after silipide and for 3% of the dose after silymarin. Plasma silybin concentrations, determined in 3 subjects, were several-fold lower than those in bile after intake of silipide and mostly undetectable after intake of silymarin. These data indicate that the bioavailability of silybin is much greater after administration of silipide than after administration of silymarin. This results in increased delivery of the compound to the liver, which represents the target organ for pharmacological action

An updated systematic review with meta-analysis for the clinical evidence of silymarin

BACKGROUND: The potential benefit of silymarin (special extract from the fruits of Silybum marianum) in the treatment of liver diseases remains a controversial issue. METHODS: For this systematic review electronic databases identified 65 papers for the search terms silymarin, silibinin, silicristin or milk thistle and clinical trial. Only 19 complied with the criteria'double-' or 'single-blind'. These publications were analysed from a clinical point of view and meta-analytic calculations were performed. RESULTS: The clinical evidence ofa therapeutic effect of silymarin in toxic liver diseases is scarce. There is no evidence of a favourable influence on the evolution of viral hepatitis, particularly hepatitis C. In alcoholic liver disease, comparing with placebo, aspartate aminotransferase was reduced in the silymarin-treated groups (p = 0.01) while alkaline phosphatase was not. In liver cirrhosis, mostly alcoholic, total mortality was 16.1% with silymarin vs. 20.5% with placebo (n.s.); liver-related mortality was 10.0% with silymarin vs. 17.3% with placebo(p = 0.01). CONCLUSIONS: Based on the available clinical evidence it can be concluded - concerning possible risks /probable benefits - that it is reasonable to employ silymarin as a supportive element in the therapy of Amanita phalloides poisoning but also (alcoholic and grade Child 'A') liver cirrhosis. A consistent research programme, consolidating existing evidence and exploring new potential uses,would be very welcome

Introduction: A welcome to the first special animal health issue of AAPS PharmSci

The goal of this special volume is to provide veterinary scientists with state-of-the art reviews in animal health and to inform human health scientists of the various challenges and collaborative opportunities associated with their animal health counterparts. The contributors are highly respected experts, providing invaluable insights into current issues and state-of-the-art advances within veterinary medicine

Development of Silymarin Self-Microemulsifying Drug Delivery System with Enhanced Oral Bioavailability

The objective of this work was to develop a self-microemulsifying drug delivery system (SMEDDS) for improving oral absorption of poorly water-soluble drug, silymarin. The pseudo-ternary phase diagrams were constructed using ethyl linoleate, Cremophor EL, ethyl alcohol, and normal saline to identify the efficient self-microemulsification region. The particle size and its distribution of the resultant microemulsions were determined using dynamic light scattering. The optimal formulation with the best self-microemulsifying and solubilization ability consisted of 10% (w/w) of ethyl linoleate, 30% of Cremophor EL, and 60% of ethyl alcohol. The release of silymarin from SMEDDS was significantly faster than that from the commercial silymarin preparation hard capsule (Legalon®). The bioavailability results indicated that the oral absorption of silymarin SMEDDS was enhanced about 2.2-fold compared with the hard capsule in fasted dogs. It could be concluded that SMEDDS would be a promising drug delivery system for poorly water-soluble drugs by the oral route