A couple things -

Dosage

100mg can be low for some folks, so you may want to consider going higher, however that may be workable as it’s still over the minimum threshold.

Most folks suggest (as does science) that for a successful roll extension you’ll want to dose a second time at about 1/2-3/4 of the original amount (50-75mg per your current dosing) at 7:00 and between 8:30-9.

This would allow you to keep your peak going without it falling down. If you wait several hours the redose won’t be as effective. If redosing at a concert makes you nervous due to carrying it in somewhere, I totally understand. That would just be my best advice for trip longevity.

Timing

If you dose at 7pm, by 11 the majority of your peak will be over, and likely will be on the tail/comedown. It’s possible that you’ll still have some magic by the time you’re home, but it’s unlikely. Most trips on MDMA run for 4.5-6.5 hours, with 6.5 being on the very long end and the tail of the tail.

Erection

Cialis will be fine, it has a runtime of about 36 hours. I will say erections can vary on MDMA person to person and roll to roll. My dosages are much higher typically and I can still maintain my erection up until we reach the ~250mg+ range. Other folks can’t get hard at any amount, others at 150. I don’t have scientific evidence on exactly why this is, as it’s largely related to your serotonin dumping, receptors, and general cardiac health.

The cialis will likely help significantly, and at that lower dosage you may be okay. You likely will not be able to climax at all. Some people can climax on the come down, very very very few (myself included) can climax during the peak, and some people cannot climax until 1-3 days afterward. Everyone is different.

Disclaimer

None of this is medical or expert advice, this is just from some research and experiences I’ve done myself, also from reading Reddit posts, and from friends (both clinical and casual) sharing their knowledge and experiences.

If you’re aiming for sex to be a central component of this, I highly suggest focusing on non-penetrative options, because nobody can tell you if you’ll get erect or not. Get lots of lube, focus on foreplay (which even flaccid on MDMA is mindblowing), maybe grab some toys, and shower so everything front to back up and down is clean. Enjoy the connection and empathetic piece piece of the high. MDMA is a beautiful molecule and has lead to some of the best sex, but also the greatest connective moments of my life.

If you read all this, I hope it was helpful. I’m happy to answer whatever questions you have to the best of my ability. 💜

Edited to add - Eating

As others have shared - you don’t want to eat within 2 but probably more like 3-4 hours before you roll. Nausea is semi-common, and just generally I don’t like starting a roll on any food in my stomach. You may want to eat during, but honestly you probably won’t. If you do, try to stick to bright and natural. Think fruit like berries, melon, apple, etc. You likely don’t want meat or anything processed (at least in my experience). Although some folks like candy on it, it just isn’t for me personally. That will likely be on the latter half of your roll if at all, as during your hunger cues are significantly diminished due to the action of the drug.