This is the current definition of psychosis (retrieved June 2014) from the Oxford English Dictionary (the OED), the standard reference work of the English language:
1. Med. and Psychol. Originally: any kind of disordered mental state or mental illness. Later: spec. severe mental illness, characterized by loss of contact with reality (in the form of delusions and hallucinations) and deterioration of intellectual and social functioning, occurring as a primary disorder or secondary to other diseases, drug ingestion, etc.; an instance of this. Cf. neurosis n. 1.
The challenge is obvious. The word "psychosis" has lost its possible meaning of simply "disordered mental state" and become a synonym for "severe mental illness."
Alternative tems we might use include "extreme experience", "spiritual emergency", "spiritual crisis", "spiritual awakening", "extraordinary experience," "consciousness crisis," or even just "madness."
It is actually somewhat distressing to imagine that authors who use "psychosis" to mean "disordered mental state" are now having their work interpreted as referencing "severe mental illness." In this context these two mentions provided by the OED are interesting:
1879 G. H. Lewes 26 Pathologists call it a psychosis, as if it were a lesion of the unknown psyche.
1907 A. R. Diefendorf (ed. 2) 153 The psychoses most apt to be confounded with neurasthenia are dementia paralytica, dementia præcox, and melancholia of involution.