We don't know of such cures. Please see a doctor when necessary, this could be anything from an allergic reaction up to neurological issues.

The itchiness and the medications I have to take to cope with it are driving me out of my mind. I already have schizophrenia, and it is like God is kicking me when I am down. Why is this happening?

For this, each one of us has to study their own individual Karma:
https://glorian.org/learn/courses-and-lectures/lecture-archive/karma-cause-and-effect (audio only)
https://glorian.org/books/karma-is-negotiable

Thank you, Marius.

I am still seeing doctors about this, but it does not seem to be going away in the immediate future.

I studied the referenced materials as best I can, as of yet, and wonder if the itchiness is karma to get me to meditate a lot more.

When I try to go to sleep, the itchiness gets worse. Sometimes it only starts as I start to fall asleep, and I am then up most of the night itching and scratching, laying there miserable trying to sleep. Lately, I have usually been taking so many painkillers at night that I enter a state of torpor. However, when I man up and take it as an opportunity to meditate, the itching is reduced. I will sometimes meditate for hours. The body rests, and I do eventually fall asleep. I get so much benefit from the meditation that it almost seems necessary. However, I am not able to keep this practice up from day to day.

Is it possible that my Being is giving me this karma to force me to meditate as I should be, which is for most of the night? How do I get myself to consistently meditate like this?

When I try to go to sleep, the itchiness gets worse. Sometimes it only starts as I start to fall asleep, and I am then up most of the night itching and scratching, laying there miserable trying to sleep.

When we go to sleep or begin to meditate, we feel these kind of things, because the physical body relaxes and we can feel the more subtle parts.This is not an esoteric statement, but we have once been told that itchiness occurs, when the skin is healing/regenerating. So it could help you to see it rather as a necessary process with good outcome. You have experienced yourself that the itchiness can go away, if you do not focus on it. So you can train to let it go completely and not be fixed on it. But as long as you keep engaging on this sensation with your consciousness, it will remain as a problem.

Is it possible that my Being is giving me this karma to force me to meditate as I should be, which is for most of the night? How do I get myself to consistently meditate like this?

Ultimately, all Karma is there to perfect us spiritually. So in a sense, yes. Work with what you have and expand the time of meditation from there in doable increments. Challenge your comfort zone in a healthy manner. But meditation needs to be seen as a lifestyle. So as soon as you are done with your meditation practice and stand up, keep up this meditative state throughout the day. If you lose it, return to it internally, as many times as necessary.

Thank you very much.