It really depends on what dose we are talking about, here, and the degree and nature of your tolerance and dependence to benzodiazepines, if any. Also important is how you dose the alprazolam - are you intending to use it as needed for breakthrough anxiety or anxiety/panic attacks, or regularly for anxiety control around-the-clock? Assuming you have little or no benzodiazepine tolerance, and assuming you have no physical dependence, and assuming you are trying to use the alprazolam as needed (not on a regular and daily regimen), the first solution I'd attempt might sound simple, but a reduction in your dose could help quite a bit. Again, that would be if what I am assuming is true. But, going with those assumptions, I am guessing you are taking, very-well possibly as doctor's orders, too much alprazolam when you do take it. The potency of alprazolam is sometimes a bit underrated by the physicians who elect to use it as an anxiolytic for someone with no benzo tolerance, from my experience and that which I have heard and read from others experiences, too, and so I find it seems a lot of doctors will write for doses of alprazolam that are too large for a decent number of their patients. Of course, everyone reactions vary, to a certain drug, be it alprazolam or whatever, even in those who have no real tolerance to the given drug. Why? Variances in natural tolerance, different medical history, different conditions of health, different complaints, and so on and so forth. Anyhow, if the scenario I came up with is an accurate one, I would, honestly, try to lower the dose.
So, if you take 0.5 mg alprazolam as needed, and this causes far too much sedation and dysfunction related to that sedation, you might want to try 0.25 mg. And, 0.25 mg is still within the 'clinical' range of dosing with alprazolam, though it considered a low dose. However, I have no issue saying that, for certain individuals with certain types of anxiety, a dose of alprazolam of as low as 0.125 mg as needed might just do the trick in taking the edge of an anxiety attack, or something similar, without causing excessive daytime sedation. I know alprazolam to be a very potent benzodiazepine, and a potent and effective anti-anxiety (anxiolytic) benzodiazepine for certain individuals, at that. Just because some people can take, with validity and for therapeutic reasons, 2 mg as a whole dose, for example, does not mean much, much lower doses cannot work with a lot of people with anxiety that responds well to alprazolam who haven't built up much of any, if any, benzodiazepine tolerance. So, do not underestimate alprazolam's very sharp anxiety-slashing powers, even at what might be considered, even by doctors, very low doses. I guess I am saying, with alprazolam, if you are experiencing that much daytime sedation, the dose is almost certainly too high for you, personally, and I'd consider not just cutting it in half, but into quarters, or even more so, depending on the dose you take.
Now, if you are in a situation where you cannot find a happy medium with a dose of alprazolam that would both take a good edge off of your anxiety, but also let you be awake and functional, you might want to consider another benzodiazepine, but honestly I think a happy medium could be found with the alprazolam. If not, I would tell you what benzodiazepine I would think a better fit for you, even if it were just a hunch, but I know really nothing of your history with benzodiazepines, your tolerance, your current dose, and how you wish to manage your anxiety (as needed vs. round-the-clock). I am curious as to how you have been taking the alprazolam, and a bit of an idea of how your anxiety operates. I hope this helps some, and I do hope to hear back from you, as I wish to help further.