I don't know whether they screened participants --
Post# of 72440
Why?
Because they would be taking other drugs, and there is no way to know if there is a drug interaction with them. In fact, I will be very disappointed if any of the participants DO have psoriatic arthritis, as i would be concerned that it would skew the results.
So let's stick to the effect Prurisol has on psoriasis, and not speculate about things that are unlikely.