Tremor is an involuntary movement of the limbs, body or head that can occur in MS. Tremor also occurs in other conditions, such as Parkinson’s disease, and can also be provoked by some medications. Tremor also can be familial. Tremor can be classified based upon when it occurs:
- Intention tremor — This is a type of tremor seen in MS. It is generally greatest during physical movement; there is no shaking when a person is at rest. The tremor develops and becomes more pronounced as the person tries to grasp or reach for something, or move a hand or foot to a precise spot. This is the most common and generally most disabling form of tremor that occurs in people with MS.
- Postural tremor — This type of tremor is generally the greatest when a limb or the whole body is being supported against gravity. For example, a person who has a postural tremor will shake while sitting or standing, but not while lying down.
- Resting tremor — generally is greatest when the body part is at rest and is diminished with movement. This type of tremor is more typical of Parkinson's disease than MS.
Tremor occurs because there are damaged areas along the complex nerve pathways that are responsible for coordination of movements. People with MS who have tremor may also have associated symptoms such as difficulty in speaking (dysarthria) or difficulty in swallowing (dysphagia) — activities that are governed by many of the same pathways involved in coordinating movement.
Tremor may make simple activities very challenging – such as dressing and eating. In addition, it can have significant emotional and social impact, especially when people choose to keep to themselves rather than feel embarrassed by tremor.
Tremor is a difficult symptom to treat. Your healthcare provider may try different medications to treat tremor. These are used off-label, meaning the FDA has not approved the drugs to treat tremor related to MS.
Eating and drinking can be challenging with tremor. Adding small weights to eating utensils may help to compensate for tremor and using a straw for drinking may be helpful. An occupational therapist
can best advise about assistive devices to aid with other activities of daily living that may be impacted by tremor – such as writing, dressing, and cooking. Physical therapists can help when tremor of the body or limbs makes mobility challenging and increases your risk for falling.
A few small studies of cannabis (medical marijuana) have suggested that it may help tremor – although further study is needed to better establish safety and efficacy.