Have you ever heard of paroxysmal symptoms?

Source MS Trust:

Paroxysmal is a term that describes the way that some symptoms of multiple sclerosis come on very suddenly, last only a few seconds or minutes and then disappear just as quickly. Sometimes this cycle repeats a few times or, perhaps, many times in a day. Some people call them attacks, clusters, surges, episodes or intermittent symptoms. Your health professionals may call them episodic symptoms.  Read on.