Phenytoin Pharma cokinetics in Experimental Schistosoma Mansoni infection

In our work concerned with phenytoin pharmacokinetics in schistosoma mansoni infected mice. We have studied phentoin absorption both in vitro and in vivo, we have found a significant decrease in PHT accumulation in intestine of infected anjmals. Theis may b e due to the histo logical changes in small intestine caused by s. mansoni infection. Unlike PHT, we have seen no effect of s. mansoni infection on p-HPPH absorption in vitro. This may be due to the difference in chemical structure.In in vivo PHT absorption studies we have found a non significiant initial decrease in PHT serum levels of infected mice. This decrease was followed by a significant in crease whtihc may be due to delayed drug excretion.In the protein binding studies we have seen no effect of concentration in the therapeutic range on PHT binding but a higher concentration a significant decrease in drug binding capacity. Both dilution of serum and s. mansoni infection produced a signification decrease in PHT binding. The decrease associated with schistosomiasis mansoni may be explained mainly by hypalbuminemia which was confirmed by our results. A significant decrease in albumin content occurred in infected animals.In the study concerned with PHT tissue distribution and serum half life we have found the drug distributed to the different tissue: liver, kidney, brain, heart skeletal nuscle and spleen, the liver concentrates high amounts of PHT. A significant increase in PHT levels in the organs of s. mansoni infected animals which may be explained by delayed drug elimination was found, also our results showed a prolongation in PHT half live in infected animals and this may be due to slow drug excretion.