Subject: was mercury used to try cure sexually transmitted diseases?

I heard somewhere that mercury was once used to 'cure' people with stds.  
The people would be cured of the disease but as the mercury settled on the 
brain they would get demetia and later die.  I would like to know if this 
is true and which disease it was used for.  I would like to know this as I 
am a student teacher teaching my students about STDs and thought this 
would be an interesting way to start the topic.

Cheers!

Re: was mercury used to try cure sexually transmitted diseases?