MS is a very individual illness, there's nothing really common about it from person to person. Symptoms really depend on where the damage is in the central nervous system. I can offer some statistics that might help with your question tho, but it's certainly not set in stone. The most common age of onset is somewhere between the ages of 20 and 40. Early symptoms might include things like optic neuritis, fatigue, spasticity, abnormal sensations like pins and needles, dizziness, and bowel/bladder problems.
I hope this helps. The national ms society is a good resource for information, you can find that site at http://www.nmss.org
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