Any benzodiazepine.
Yes,
yes.
Why would you want to do that, xanax will just kill your trip and make you sleep.
Yes, antibiotics do come in suppositories. It isn't real common, but they are available and are used in some cases.
Herbal xanax is not even close to as potent even in doses 100x stronger than xanax (milligram per milligram). Xanax is prescription depressant and herbal xanax is a blend of herbal supplements. It is a misleading name and will not make you feel the same way even in huge doses.
Yes it can. They even make morphine suppositories. The bioavailability is a bit higher that way.
no
This is rare - but has occurred in some people taking Xanax.
yes
there a nice mellow buzz. and make you relax.
Birth control suppositories are one of the least effective methods to begin with. Withdrawal is more effective than spermicide used alone. Consider getting some condoms and throwing out the expired suppositories.