I have had visual and auditory hallucinations all my life, from childhood. I was never afraid to try any hallucinogenic drug due to my normal state. I routinely hallucinate without the use of drugs. I do not suffer HPPD, it started before I ever tried drugs.
When I tried Salvia Divinorum I was sober. I had not used any drugs for more than 2 weeks prior to my first experience. I tried 10X in a bong packed with ice. I packed the bowl and smoked it, taking care to hold my breath for a full 20 seconds each time I filled my lungs. I smoked 5 bowls total the first time.
The first major effect was a 'head rush' or the feeling of 'light headedness'. The rush lasted a few minutes after each bowl. After the rush I felt sober. I walked around the room and noticed that I was NOT hallucinating for the first time in many hears. After the fifth bowl I gave up on the Salvia. I then used Nitrous, but the result was boring with little effect.
The next day and for 16 days I noticed that I was not hallucinating. 17 days after my first use of Salvia I began to have minor hallucinations. One month after my first use my hallucinations were back, but quite mild.
I do not perceive alternate realities but I feel calm and entirely 'real'.
I have tried Salvia a second time, last night, and had the same result. I had a craving to get 'high' last night. I smoked the Salvia and now have no desire for intoxicants. It was not an unpleasant experience at all.