It may be little rough, but you can taper Xanax without crossover. If the one that supports taper but not crossover would work with you, you may try. It could work. Now, if you decide to taper directly Xanax, first, it would be great if you could get Xanax XR + regular Xanax. Then you could taper something like this:
1) morning: 1mg XR + 0.5mg IR / evening 2mg XR =3.5mg
2) morning: 1mg XR + 0.5mg IR / evening 1mg XR + 0.5mg IR=3mg
3) morning: 1mg XR + 0.25mg IR / evening 1mg XR + 0.50mg IR=2.75mg
4) morning: 1mg XR + 0.25mg IR / evening: 1mg XR + 0.25mg IR =2.50mg
5) morning: 1mg XR only , evening 1mg XR + 0.25 IR =2.25mg
6) morning: 1mg XR , evening 1mg XR=2.00mg
7) morning 0.5mg XR + 0.25mg IR / evening: 0.5mg XR + 0.50mg IR =1.75mg
8 ) morning: 0.5mg XR + 0.25mg IR / evening: 0.5mg XR + 0.25mg IR =1.50mg
9) morning: 0.5mg XR + 0.125mg IR / evening: 0.5mg XR + 0.25mg IR =1.375mg
10) morning: 0.5mg XR + 0.125mg IR / evening: 0.5mg XR + 0.125mg IR =1.250mg
11) morning: 0.5mg XR / evening: 0.5mg XR + 0.125mg IR =1.125mg
12) morning: 0.5mg XR / evening: 0.5mg XR=1mg
At this point you would have to resort to IR. You could spread your dose something like:
13) morning: 0.25mg IR / afternoon: 0.125mg IR /dinner time 0.125mg /before sleep 0.25mg/during night if you wake up 0.125mg=0.875mg
14) morning: 0.125mg IR / afternoon: 0.125mg IR /dinner time 0.125mg /before sleep 0.25mg/during night if you wake up 0.125mg=0.750mg
15) morning: 0.125mg IR / afternoon: 0.125mg IR /dinner time 0.125mg /before sleep 0.125mg/during night if you wake up 0.125mg=0.625mg.
16) Next eliminate the night/if you wake up dose, so, morning: 0.125mg IR / afternoon: 0.125mg IR /dinner time 0.125mg /before sleep 0.125mg=0.5mg.
When you get this low it is up to you to make the calls what doses go out first, based on your symptomatology. Of course this is a provisional tapering schedule that could be implemented with Xanax (alprazolam) only. Usage of extended/slow release form in combination with regular instant release make Xanax easier to taper. It is not easy but neither is tapering diazepam or clonazepam. You would modify, if you choose to use Xanax to taper of Xanax, speed of taper, what dosages go low/out first (are you more anxious in the morning, during day or at night), or even if you would try to swap that last milligram of Xanax to 10 milligrams of Valium, but I believe that you could do it in this fashion.
Now, I would like to say that I have read some people state that they felt better weaning off original short acting benzodiazepine then by substituting to long acting one. For others , switching to diazepam or clonazepam (I would say to go with diazepam rather than clonazepam) was more beneficial. I am dependent on benzodiazepines for more than 15 years now. I tried to taper on few occasions but when I get into <10mg territory my world starts falling apart and I never made it to the other side. Last time, 5 years ago, I got down to 4mg but suffered from such multiplicity of disrupting and painful symptoms that I think I got PTSD from it. I so much wanted to be off diazepam before my child was born, but neither that was enough to overcome my personal subjective hellish experience. But I will try to do it again. I am "stable" (you are never stable on benzos after 15 years, but I can function with this much tolerance withdrawal) at 20mg diazepam and at the moment I need this stability so badly. But I will try to taper off again. Benzodiazepines are monsters. They take away your CNS and with it every aspect of your functioning. But it is easier for some than the others and I truly hope that you will not have as much problems as I did/do. I have also read that people have gotten of benzos with very little problems even after many years of use. So there is always hope
Stay safe.
Soma