I went to see a physician, who told me that I had "intention tremor," and that I should consider taking beta-blockers if I wanted to continue to work in the lab. Oh, yeah - and that he couldn’t tell me what was causing it.
Then, about 10 days after it started, my tremor simply went away (and I spent the next year blissfully filling and emptying tiny vials without a problem). These days I might notice an occasional slight tremor when I am trying to use tweezers or thread a needle, but for the most part, it doesn’t interfere with anything I am trying to do. However, my husband and other people have noticed tremor in my head or hands that I am completely unaware of.
What Does it Feel Like?Tremors are involuntary muscular contractions that result in a rythmic back-and-forth movement of a specific body part. While the hands are usually affected, tremor also can affect legs, the vocal cords, head and trunk.
There are two types of tremor in MS:
- Intention Tremor: This is the kind of tremor that occurs when you reach for something and your hand starts shaking. The closer you get to your target or the smaller the movement required, the more your hand or arm will shake. This is the most common type of tremor.
- Postural Tremor: This is a shaking that occurs while you are sitting or standing and your muscles are trying to hold parts of your body still against the force of gravity.
What Causes Tremor in MS?Most MS tremors are caused by demyelination to the cerebellum or the nerves leading to or away from it. The cerebellum is the part of the brain which controls balance and coordination, and it helps makes movements of the limbs, mouth and eyes smooth and fluid. Tremor can also be the result of demyelination in the thalamus and the basal ganglia.
How Common is Tremor in MS?It is estimated that up to 75 percent of people with MS experience tremor at some point. Usually tremor develops after people have had MS for at least five years. Tremor can occur as a relapse symptom and disappear on its own or after a course of corticosteroids, however, it is common for residual tremor to remain.
How Severe Can it Get?For the majority of people, tremor is simply annoying and can be embarrassing. However, a tiny percent of people may experience tremor so severe that it becomes impossible to perform necessary tasks like eating, drinking or getting dressed.
- Neither intention tremor nor postural tremor happen when a person is asleep or even just lying down and the muscles are relaxed. If you have a tremor while you are resting, this may be the result of something else, like a drug side effect, and you should mention it to your doctor.
- Although postural and intention tremor are by far the most common, some people experience tremor of the jaw, lip or tongue which may affect their ability to speak clearly. Also, nystagmus (“jiggling eyes”) is also considered a form of tremor by some.