There are little reports about this combo, so SWIM decided to give it a try.
He mixed S. divinorum plain leaves with Turnera Diffusa (aka Damiana) dried material and vaporized the mixture.
The result was a mild S. divinorum trip, with the "Salvia wheel" running slower than usual. Don't know if that was random or caused by the Damiana.
Anyway, what is interesting is that a successive vaporization of S. divinorum (alone) resulted in a prolonged Salvia experience, the peak, but more remarkably the comedown, was extended twice or three times.
So it could be that the Damiana acts as a Salvia extender, if it was so, it would be a great finding, right?
Next time SWIM will vaporize Damiana first, giving her the time to express, and then take Salvia.