Get headaches after rain. similar to sinus headache. advised by gp to use prednisone (cortizone) as needed. it works, but dont want to use continually?

? Allergy: to a fungus, possibly Fusarium, that flourishes after rain in a humid environment. You want to see an allergist/immunologist for evaluation if you have access to one, or an ENT specialist. Meanwhile use saline nasal washes on regular basis at least once a day, and OTC mild steroid nasal spray (e.g. Fluticasone) after flushing your nasal cavity with saline, rather than using prednisone, good luck