Use Natalizumab Monitoring, PML Risk, and Pregnancy Planning to guide the working diagnosis and next step; let the main risk or management issue drive escalation, treatment choice, and follow-up.

Because the risk of developing progressive multifocal leukoencephalopathy rises steadily over time, many clinicians will look to transition individuals off natalizumab after about two years of continuous use.; Depending on the specific molecule's pharmacokinetics, most protocols recommend a brief washout period of 1 to 3 months before attempting to conceive.; Since their safety profiles and efficacy levels vary quite a bit, it allows us to easily customize the selection to the case.; Fingolimod, on the other hand, does not carry that same steep time constraint and can often be safely maintained for several consecutive years.; Key management decisions should stay tied to the clinical pattern and follow-up needs.