The episodes could be due to postural hypotension (blood pressure falling with change of position), internal ear problems, cervical spondylitis, anemia, GERD,
hypoglycemia or low sugar, stress and anxiety and some endocrine problems.
In your case I would look at anemia, hypoglycemia, endocrine problems and GERD first. Stress and anxiety definitely add to the problem. However first get the above medical conditions excluded. GERD is common with steroids.