You really must tell us most of your medical issues otherwise a correct determination cant be reached, although we dont diagnose here or recommend.
Labyrinthitis is a viral infection of the inner ear, I guess thats why you are taking amoxicillin to counter the infection. Prochlorperazine is taken for nausea from cancer chemotherapy. I dont know the connection between the two in regard to causing you not to sleep but we all dont respond the same to different reactions and side effects from drugs.
You may wish to consult with your doctor. And I do urge you to ask more questions of your doctor regarding your medications.
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