I believe the maximum FDA recommended dosage is either 6 or 8 mgs a day for alprazolam (and I want to say 6- that doesn't mean a doc can NEVER prescribe more than that (I have seen 8 before but pretty damn rarely))- and that would be someone diagnosed with a medical condition where they have a level of severity that requires the maximum dosage, are under a doctor's care, may have slowly gotten there over a long time (probably years), etc. Also, as much as we hear about the war on drugs, the pharmaceutical industry has a lot of influence as well. My sis became a nurse practitioner last spring and she definitely is not someone who is pro-drug war in general (she thinks HAT (heroin assisted treatment for addicts) is something we should look into and she would support it if evidence continues to show that it helps addicts be healthier, more functional, reduced crime, could be safely and effectively implemented, etc. just to show where she is at) and she says they are being taught that benzos should not be prescribed longer than 6 weeks (basically started with other medication that takes time to kick in and slowly tapered as it kicks in) or given infrequently as a prn (there may be exceptions such as when benzos are prescribed for certain conditions other than the basic mental health ones we associate them with). Reason being that benzos cause severe physical dependence (a worse dependence than opioids more often- the only positive I think is that with MANY people (but definitely not all) the use is not as complusive so maybe more people are successful at tapering without having the medication dispensed in a facility or by a loved one; but definitely some people don't seem to be able to do so) AND many people say that they completely lose their effectiveness once a full tolerance to the dose is acheived (by comparison most doctors think that while people gain a tolerance to the sedating/euphoric effect of opioids they may indefinitely or long term keep their ability to help with pain if not abused) and this was my experience when RXed clonazepam- a dosage increase would help for a little while but in the long run I actually had more anxiety due to starting to feel WDs in between doses, being anxious about having a physical dependence that even though I was on relatively low dosages I percieved as severe, etc.
That said- I don't know if, in the sense you are asking, benzos would KILL you if you took a stable dosage everyday, didn't OD, didn't have problems not associated with the drug like not exercising, etc. I can't really say I've heard of people having liver failure or failure of other organs from taking them long term (as in the way alcoholics often have severe liver damage and failure as well as a lot of other conditions that are directly deadly due to long term abuse). But the WD can kill you- and even if you think "well, I can afford this, acquire them, plan in advance, etc." in our society with the way we treat drugs it is always possible. I've seen doctors pull people cold turkey (something they should not do unless for some reason benzo use has become so risky due to some condition (and I can't think of one off the top of my head) that further doses have a greater risk to the patient than abrupt cessatation) when they have the patient in a controlled environment and seen people have seizures and end up in the ICU. I've seen people end up in jail while on benzos (and it isn't that rare- not only could you be arrested for possessing benzos if you don't have an RX (maybe not if they are an RC- although I have a hunch you could be held in some cases until it is determined it ISN'T a controlled substance which could take a while- I know someone who was prescribed oxycontin and went out with a few not in their bottle nor with the slip saying they are prescribed it, got grabbed, and sat in jail for like 2 days while it was "verified" (shouldn't have taken that long but if the police decide they really don't like you....and lab tests could take infinitely longer)) and they seem to be a substance that sometimes, at doses enough for the person to black out or lose inhibitions, contributes to illegal acts (they are sometimes called "felony pills" in some of the correctional facilities I've been in due to people taking some, blacking out, and coming to incarcerated) though to be fair statistics seem to show alcohol to probably be the MOST risky substance (of fairly commonly abused substances) when it comes to this regardless of what the media says about meth, pcp, and certain other drugs causing insane violence.
Then there are accidents- though this could be said for other substances as well (alcohol again being the substance most associated with accidents (and don't think, and I doubt most BLers would think this way, that alcohol is less dangerous b/c of its legal status- the reason alcohol is legal is a)prohibition didn't work and caused more problems than it helped (same could be said for almost every drug now controlled) b) it has a long history of use culturally and the other main drug classes that were banned were usually associated with minority groups)). But it is something to think about.
I'm not trying to demonize benzos- I know plenty of people that have taken them and not had problems (ocassional use and certain medical conditions) and admit that I sometimes take them as well. But it is important to remember these things when we use as it may lead to safer choices or at least safer use. I would recommend, for a first step, trying to get your dosage down. It may be possible to cut your dosage a little bit even without switching to a long lasting benzo because a) it does take a bit longer for tolerance/dependence to reach its MAX with benzos compared to say opioids b) it does seem like people do sometimes tolerate drops in a dose of alprazolam (small drops) when the dose is high. It would be BETTER if you are dependent to switch to a long acting benzo (diazepam ideally) but I know that isn't always something that is always possible (although I do think that if gotten from a good supplier some of the RC benzos may be better for tapering than alprazolam, but there are problems that come with RCs much the same as illegal drugs).