Sorry to say it but fuck all, unless injected or PR (per rectum) administration, even then you will still be getting visuals etc. just feeling less anxious and you will have reduced both cardiac stroke volume (pressure of the blood exiting your heart) and any tachycardia (fast heart rate) experienced. Same route of administration as you would do for a seizure because diaz takes 3 hours to reach maximum plasma concentration and then around another 30 to be excreated/eliminated from the body. Xanax or Lorazepam say 2mgs of eigther sublingual is way more effective than oral or sublingual diaz and will reduce anxiety/aggitation in 15-30 minutes. Some anti psychotics are very effective but may have adverse effects on your cardiovascular system or liver/kidneys etc. I think a small dose of Seroquel (Quintiapine) say 25-50 mgs should be ok, I've taken that kind of dose for a 30mg 2c-i trip that had become a little overwhelming. I often take Mirtazapine 30 mgs to reduce the effect of psychedelics. It has both an SSRI component thought to have a palliative (reduces/kills) effect on psychoactive substances and a anxiolytic effect (reduces anxiety). For some reason Clonazepam does reduce both anxiety and some of the tactile/visual stimulation psychedelics cause, for me at least.
Benzo's are great for reducing anxiety, heart rate and stroke volume all of which are essential if you think your going to have cardiac issues (and probably should not take drugs that raise heart rate and bp) or notice the following: "shit my right eye's pupil is massive and my lefts normal size. My right does not get smaller when light shines in it but the left reacts as normal... fuck my head hurts and I feel dizzy." Possibly you may have raised intercranial pressure and may stroke, pass out unconcious or simply cone after going unconscious. (coneing is basically when their is so much pressure in the brain from trauma/stroke/bleed etc that the brainstem and brain are forced into your chest cavity via your neck and spinal column, nice!) That said it usually only occurs as a result of massive trauma such as MVA not taking a dose of psychedelic drugs.... however raised intercranial pressure is an issue if the substance is highly vasoconstrictive and increases heart rate, stroke volume etc. for example MDPV. May cause a stroke. Know what your taking, what your safe dose level is, for example most people take 25-30 mgs Allyescaline, while I find 15 mgs gives me a nice mild experience and I'm not overwhelmed by any visual hallucinations just CEV. If you need to have an abort button for every psychedelic experience perhaps a lower dose or the drug itself may cause you adverse effects. I can't take Tramal, gives me the shakes all over, other people can without any adverse effects. You may find some psychedelic drugs are great but others you don't react as well too, it's all about an individual users pharmacodynamics in vitro ie: how the drug effects different parts of the body and brain in one person may be slightly different to the next person etc. A bad trip is eigther an overdose, the chemistry in the clandestine LSD is dodgy or your own mental state, setting etc was not right when you took the trip. I've done... fuck knows? I ate that much LSD a few years back I got no effect from taking 4 trips (cupids??) spaced over 2 hours. I'd also had 2 days without using LSD (or anyother psychedelic drug for that matter).... not even close to the amout of time your body needs to recover from sustained week long LSD tripping binge of 4-5 trips every day for a week. I would not recommend this as a method to stop a bad trip as you would have already had 7 or so days of tripping out of your mind
! On a night out in my early 20's if I decided to do acid I'd pop 4-5 trips per night (night owls, love ohms, dragons, superman etc.) Really fries you the next day though. Also bad idea when you have just broken up with your significant other half... might end up bawling your eye's out about it to a complete random who is too scared/bewildered to do anything but look about for help while saying "there there it's all going to be ok" About 15 minutes later jumped up didn't give 2 shits, went off to the pub for several drinks (which did nothing) of some tasty beer... yes tripping makes you think and do weird shit. Hope some of this babble is of help.