Outwardly, essential tremor can sound and seem, well, a bit benign. It's a name that sounds something less than severe. But the neurological disorder is much more than a minor annoyance. It's a life-changing condition that prevents millions from living the lives that they deserve. There's a trembling in the hands, an involuntary movement of the arms, legs or head, maybe a slight quiver in the voice. There are few approved drugs to manage the condition. For many people the drugs may not help reduce disability and the only option might be to adapt their lives to living with tremor. That is, until deep brain stimulation (DBS) came along. What is Essential Tremor? Essential tremor is largely characterized by the involuntary rhythmic shaking that gives the condition its name. The National Institutes of Health reports that the neurological disorder affects as many as 10 million people in the U.S. But despite how common the condition is, it's frequently confused with another neurological condition: Parkinson's disease. The conditions share a common and significant symptom: tell-tale tremors that typically start in the hands and progressively migrate out to the rest of the body. Unlike the shaking that's associated with Parkinson's, which most frequently occurs when the body is at rest, essential tremors most often happen when the body is in motion, the International Essential Tremor Foundation says. They're also bilateral — meaning they happen on both sides of the body. The trembling most often occurs in the hands — especially when attempting simple tasks, such as tying shoelaces or using a spoon or a pen. The neurological disorder can also trigger other symptoms, including an unsteady voice or problems grasping things, says the National Institute of Neurological Disorders and Stroke. It's thought that about half of the cases of the disorder stem from genetic predisposition affecting the parts of the brain that control movement. The Past: Endless Medication Because there isn't a great deal of knowledge around what causes essential tremor, healthcare providers were, at first, not able to treat the disorder at its source. Instead, they'd prescribe medications that treated the symptoms instead of the disease. Four main types of medicines, according to the Mayo Clinic, were commonly used, and each caused side effects: Beta blockers, which are often used to treat hypertension, have been prescribed to help calm tremors. They're not appropriate for everyone — especially for those with asthma or heart issues — and can cause drowsiness, fatigue, faintness and a slowed heartbeat. Anticonvulsants, which treat epileptic seizures, have also been shown to help calm tremors. As beta blockers do, they also come with side effects, such as drowsiness and upset stomach. Tranquilizers, such as Xanax, which treat anxiety, are prescribed for tremors, too. But they're not without side effects, and they can also be addictive. Botox injections have been shown to relieve tremors for up to three months, but they can lead to weakness in the fingers.