Nora Fitzgerald is a Social Science Analyst at the National Institute of Justice.
K. Jack Riley, Ph.D., is Director of the Criminal Justice Program at RAND.
The above is good information and within it is this article
"The unique problems of not remembering
LEARNING FROM VICTIMS"
https://www.ncjrs.gov/pdffiles1/jr000243c.pdf on page 4 by Gail Abarbanel, LVSW in which she explains a lot of the unique problems for victims of drug-facilitated rape specially in which the victim has no memory of the sexual assault.
One of the key points is how the victim is prevented from exercising self-defense during and after the assault because there is no memory. Drugging someone should be considered a crime in itself. There is more psychological trauma as a victim of drugged rape because there is no memory of the rape and you imagine the worst and you are unable to trust anyone because you do not know who else may have been involved. I highly recommend reading "Learning from Victims" as people seem to think that not knowing what happened to you makes drugged rape less traumatic than violent rape when it is way worse.