“California rocket fuel” is a medical slang term for the combined administration of mirtazapine (a NaSSA) and venlafaxine (an SNRI). This combination is usually used in the treatment of severe and/or treatment-resistant depression. Like other combination therapies, when used as an initial treatment, the mirtazapine and venlafaxine combination resulted in a remission rate - as did the combination therapy of mirtazapine and fluoxetine - over twice that of fluoxetine SSRI monotherapy.
References
California rocket fuel Wikipedia(Text) CC BY-SA