Anna,
Thanks for your comments and yes, I do agree that psora is more difficult to shift then syphilis. I have found that in my experience the two miasms bounce off each other and both are difficult to shift. Perhaps this is because of the mercury.
The most frequently used anti mercury remedy in my practice is hepar sulph. It seems to come up regularly and helps move things on. There are others of course as there are many remedies to combat mercury.
I think it is possible to effects cures where mercury is constantly poisoning the system as it does from teeth. Some people are more mercury sensitive than others but it is possible for the body to deal with it by using an indicated anti mercurial remedy when progress is halted for no other reasons. Also to start a course of treatrment, I almost routinely give Psorinum on day one followd by Hepar Sulph (for example) on day two to remove to psoric and mercurial blocks to the indicated remedy.

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Professional homoeopath interested in general discussion, ideas etc.