I have had the same type of headache described here (intense pain when bending over, coughing, sneezing or bearing down) for almost two years. I've also seen an acclaimed upper cervical chiropractor for nearly that whole time, but unfortunately the adjustments didn't help this headache at all.
Early on, my neurologist diagnosed it as viral meningitis, a conclusion drawn from an elevated white blood cell count in the spinal fluid, from a spinal tap. However, I'm skeptical of the diagnosis, because if it was viral meningitis I should have been over it within a year, but after nearly two years I still have the same headache. I did have an MRI and various other tests which were all normal. It's still a mystery.View Thread