Charoenngam N.Holick M.F.Mahidol University2025-11-302025-11-302024-12-01Neuroimmunology Reports Vol.6 (2024)https://repository.li.mahidol.ac.th/handle/123456789/113308A 36-year-old male presented with 2 months of left-eye visual disturbance and was diagnosed with optic neuritis due to probable multiple sclerosis (MS). He was advised to undergo periodic ophthalmology follow-up without immunosuppressive treatment. Due to persistent symptoms, he expressed interest in very high-dose vitamin D<inf>3</inf> therapy of 54,000 IUs/day (1,000 IUs/kg/day) along with a zero-calcium diet. After starting the therapy, he experienced sustained symptomatic improvement of visual symptoms over 4 years, along with radiological stability of the optic neuritis lesion without developing hypercalcemia. This case supports the potential therapeutic efficacy of very high-dose vitamin D for MS.NeuroscienceMedicineArticleSCOPUS10.1016/j.nerep.2024.1002242-s2.0-1050227586212667257X