Drug metabolism, pharmacokinetic pregnancy

The total plasma concentration of drug falls, especially towards the end of pregnancy, due to haemodilution, but the therapeutically important free (unbound) fraction in plasma is less affected. In practice, the patient s clinical state is observed closely and the dose of drug is increased if seizures occur more often than expected. Hepatic drug metabolism tends to increase during pregnancy. After delivery, the pharmacokinetics revert to the prepregnancy state over a few days. 

In addition to the above studies, a number of studies examining the pharmacokinetics of the test material need to be conducted to show whether the drug crosses the placenta, whether it is excreted in milk and whether pregnancy affects absorption, distribution, metabolism or excretion. 

Ovarian hormones may influence pharmacokinetic parameters, and the physiological state of pregnancy can affect a drug s distribution and metabolism. 

Example Ibuprofen (Motrin, Advil, Nuprin) naproxen (Naprosyn) (Aleve is a similar OTC drug) Oxaprozin (Daypro) ketoprofen (Orudis). Route PO Pregnancy category B Pharmacokinetic Absorbed from the GI tract, metabolized in the liver and primarily excreted in urine ... 

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