Spontaneous intracranial hypotension is characterized by orthostatic headaches in conjunction with reduced cerebrospinal fluid volume(CSF) and characteristic imaging findings. We report the clinical course of six consecutive patients with spontaneous intracranial hypotension who were followed between 4 months and 2.5 years. The characteristic orthostatic headaches were present in five patients. Diffuse pachymeningeal enhancement on brain magnetic resonance imaging (MRI) was evident in all cases. CSF detected elevated protein content in three of six patients. In only two of our six patients a first epidural blood patch resulted in complete symptom resolution lasting 4 months and 1 year. Four patients received a second epidural blood patch and one patient also received a third. In four patients, follow-up brain MRI revealed re-occurrence of the typical MRI features and all of them suffered from orthostatic symptoms at this time. Only four patients are free of complaints after an average follow-up period of 10 months. Symptom relief within 7 days from an epidural blood patch is accepted to be diagnostic for spontaneous intracranial hypotension. However, our data illustrate that the clinical course of the syndrome is very unstable and the epidural blood patch is less effective than widely accepted.