Exhilarating.
Rash or impetuous.
Intellectual.
Intoxicating or stupefying.
Tending to upset the mind or senses.
Impressible.
Based on subjective reactions or feelings; not systematically researched or arrived at.
Based on impression rather than reason or fact; based on trying to impress somebody rather than trying for accuracy.
Pertaining to or characterized by impressionism.