(If this was a rant, it would be welcomed anyway, everyone feels frustated once in a while in their path for regular lds )

I can't really comment on seroquel because I've never used it, but I can tell you that maybe it's yourself who is preventing you from lucid dreaming. If you believe you can't have lds with the medicine, then your brain will actually block a huge percentage of possibilities.
Instead, try to think:

- Am I using the right approach?
- Am I using the best technique for me? How long have I been practicing it? How do I perform it? What results did it gave me so far?
- Do I have regular sleep? Do I end up going to bed anxious about my next lucid dream?
- Am I able to notice my dream signs? Am I focusing on the most common ones to and make sure I will know I'm dreaming when I perceive them?

Sometimes, one of these questions might be the answer on why you aren't having lucids. Remember, you can always do more: work more on your dreamsigns, more in your dream journal (reading it before bed/during WBTBs), trying SAT, resume my reality checks only when I see odd things/certain dream signs.

I don't believe that what you are taking can prevent you from lucid dream, at least a few per week, especially after what the person above said. I know everyone acts differently, but in my point of view you just need to convince yourself that you are the one in charge: you and yourself are the ultimate responsible for your success. I'm sure if you believe you will start having more lucid dreams. Good luck!