If you experience great difficulty tapering off of a benzodiazepine, even if you do it in tiny increments over a long period of time, there are ways to help with this. This I believe is mentioned in the Ashton Manual, which discusses tapering schedules. I unfortunately cannot find any of the websites that used to be around that included these schedules. I guess they got taken down for copyright infringement...

The shorter the half-life/duration of action of the benzo, the harder it is to taper down and discontinue because the withdrawal symptoms are way worse.

@metamorphosis12 mentioned already about GABA/glutamate but didn't really go into much detail. Benzos work by potentiating (making more effective) the activity of GABA at GABA-A receptors. GABA is an inhibitory neurotransmitter, and cancels out the activity of the excitatory neurotransmitter glutamate. As with alcohol withdrawal (alcohol works extremely similarly to benzos on GABA-A receptors), when you try to reduce the dose of a benzo, the activity of GABA will decrease and glutamate activity will increase. For some people, this causes intolerable withdrawal symptoms and makes it incredibly difficult or even impossible to taper/withdraw (both from benzos and alcohol) without some kind of intervention.

One method (I believe which is mentioned in the Ashton Manual) is to do a cross-taper from the benzo you're trying to withdraw from over to Valium. Valium is an extremely long-acting benzo with a half-life of 30-60 hours and its active metabolite having a half-life of 30-100 hours (according to Epocrates). Even Klonopin, which is also considered a long-acting benzo, has a shorter half-life than Valium (20-50 hours). Despite this, Klonopin for whatever reason or another tends to be one of the worst benzos for causing withdrawal symptoms (Xanax is probably the number one worst). One method is to convert the total daily dose of the benzo being withdrawn from into the equivalent amount of Valium and then slowly withdraw from that. Another method (I think this is how it works) is to slowly decrease the withdrawing benzo while slowly introducing and increasing the Valium until you're taking the equivalent amount of Valium, and then coming off the Valium very gradually. There are even ways of dissolving valium in a specific volume of water and drinking just enough to get the right dose to taper off in smaller increments than are possible with even the lowest dose of Valium (2 mg). Also, sometimes the psychiatrist/doctor will have smaller doses of Valium compounded by a compounding pharmacy (this tends to be pretty expensive though).

This link gives an example of a tapering schedule from an unmentioned benzo (probably Xanax) by tapering off of it without Valium, and an example schedule for tapering off Valium after converting it from its equivalent dose of Xanax (the first method I mentioned). Unfortunately, I can't find any example of the second method I mentioned...

So as of 8/23, you said you were down to 1 mg Klonopin. There are many different benzo equivalency tables, but I'm going to refer to the one available in Epocrates, which says that 0.25 mg Klonopin = 5 mg Valium. So 1 mg Klonopin = 20 mg Valium. Disclaimer: I am not a professional, you need to consult your doctor before trying this! So one way would be to switch straight over from 1 mg Klonopin to 20 mg Valium and go down from there in tiny increments (e.g., 2 mg or smaller), or you could gradually decrease the Klonopin in 0.125-0.25 mg increments as you slowly increase the Valium in equivalent dosage increments (which would be 2.5-5 mg), and then when you've reached 20 mg Valium + 0 mg Klonopin, slowly decrease the Valium in tiny increments (e.g., <= 2 mg). How frequently these dose adjustments occur is up to your doctor. You may need to remain on certain dosages of Valium for extended periods of time while tapering (the tables in the link show this).

BuSpar has a reputation for being pretty worthless for anxiety.

It's very concerning that you're on two antipsychotics, though. That's antipsychotic polypharmacy, and Steven Stahl says that's an absolute no-no and reserved for extremely treatment-resistant cases of psychosis associated with severe violence or homicidal ideation/attempts. I would definitely talk with your pdoc about that, and picking one of them to take at a time. Both can be effective at reducing anxiety, but Zyprexa would probably be the better option (though it shouldn't be a long-term option because of its effects on glucose metabolism and its ability to cause diabetes).

The combination of Effexor and Remeron is pretty effective for depression. Stahl refers to it as "California Rocket Fuel." However, Effexor may not be the best antidepressant for anxiety. What dose of Effexor are you on? If it's anything over 75-150 mg, it may be making your anxiety much worse. High-dose SSRIs tend to be the antidepressant option of choice for treating severe anxiety, but if these don't work, there are second-line options available.

* Cymbalta is an SNRI (like Effexor) that is often used for anxiety and seems to be quite effective and better tolerated than Effexor for that indication.

* There is a pretty new class of antidepressants called serotonin modulators and stimulators (SMSs). This includes Viibryd and Trintellix. Viibryd is basically an SSRI + BuSpar (i.e., a weak 5-HT1A partial agonist), except it's a much weaker SSRI (occupying ~50-60% of the serotonin transporters in the brain instead of ~80% like most SSRIs) and a much stronger version of BuSpar (stronger binding to the 5-HT1A receptor, a serotonin receptor, than serotonin itself, so that it stimulates it even in the presence of increased serotonin levels). This enables the same antidepressant/anti-anxiety effects of an SSRI without all the side effects associated, and it is proposed to act much quicker than an SSRI alone. It also causes indirect dopamine release by means of stimulating postsynaptic 5-HT1A receptors. Trintellix is a lot like Viibryd in that it is an SSRI, but instead of a partial agonist at 5-HT1A, it is a full agonist. It also has additional actions at other serotonin receptors, including 5-HT1B partial agonism, 5-HT1D antagonism, 5-HT3 antagonism, and 5-HT7 antagonism. Basically it does the same thing as Viibryd except it also enhances serotonin release and increases dopamine, norepinephrine, acetylcholine, and histamine in the brain, which theoretically equates to improved antidepressant/anti-anxiety effects with the benefit of improved cognition, memory, circadian rhythm regulation, and wakefulness/alertness.

* A few of the older tricyclic antidepressants are good for anxiety, mostly imipramine (Tofranil) and clomipramine (Anafranil). Anafranil is the absolute most potent SNRI on the market (low doses work on serotonin reuptake inhibition, and even the lowest dose of 25 mg is more potent than the max dose of some of the newer SSRIs, but as the dose increases, its active metabolite, N-desmethylclomipramine, increases, which acts as an extremely potent norepinephrine reuptake inhibitor). The tricyclics tend to have more side effects than the SSRs/SNRIs since they're "dirtier" drugs.

* Lastly, the MAOIs can be a good option for anxiety, especially Nardil. These are largely not prescribed because of their dietary restrictions and drug-drug interactions that can be fatal if not followed. However, these meds are extremely effective (probably the most effective antidepressants, especially in those with treatment-resistant anxiety and depression), and are actually much better tolerated than even the SSRIs/SNRIs. Most doctors/psychiatrists refuse to prescribe them simply because they have no experience with them and aren't familiar enough with the dietary restrictions and drug interactions... Basically they're afraid of them because of what they don't know about them.

I'm going to reiterate that BuSpar is known for being worthless. If it didn't work the first time, it probably won't work if you try it again. The max dose is 60 mg, but sometimes is prescribed as high as 90 mg for severe anxiety.

OP already has taken pregabalin (Lyrica).

Also, if OP cross-titrates to something like Valium, seizures might not be as much of a concern.

OMG YES I SECOND THIS. One of the old, first-generation antipsychotics, Stelazine, worked miracles for my anxiety. I was completely housebound (unable to leave my house due to anxiety) for months before I started it. I begged my pdoc for it, and she reluctantly agreed to prescribe it to me. I started with just 1 mg twice a day, and it was better than any benzo I've ever taken. Within a few days, I was able to leave the house and even enjoy myself while I was out. I did end up on 2 mg three times a day, which is the max dose for anxiety, which started to make me a bit too sleepy. So I had to stop taking it and move on to something else. But Stelazine is definitely one of my stand-by medicines for extremely severe anxiety.

Propranolol is good for anxiety, but to my understanding it is more for the physical symptoms of anxiety (tremor, racing heart, chest pain, etc.) I have never heard of it being used for benzo withdrawal, but I wouldn't be surprised if it was effective. I don't think propranolol relaxes blood vessels though, I think that would be more of what the calcium channel blockers do.