How should I correctly handle the ‘EHC continuous fraction’ parameter?

[HydrangeaMF]

Hello, everyone in the OSP community.

I am building a small-molecule drug model that includes the ‘P-gp’ and ‘BCRP’ transporters. I have found that the ‘EHC continuous fraction’ parameter has a significant impact on the plasma concentration-time curves generated by my simulations, and causes abnormal shapes at the peaks of these curves under multiple-dose regimens.
I have reviewed the forum documentation and understand that this setting relates to the enterohepatic circulation; however, there is currently no literature data available for my target drug to support detailed bile excretion parameters. Therefore, I want to know:

• If I wish to simplify the modelling of bile excretion, can I set the EHC continuous fraction to 1, as is done in many validated OSP models?

• If the transporters of the target drug involve transport to the gallbladder, is it necessary to account for this parameter when modelling?

[github-actions[bot]]

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