Pharma giant GlaxoSmithKline has received FDA approval on their Horizant Extended Release Tablets used to treat restless legs syndrome, or RLS. Restless legs syndrome is a neurological condition that is characterized by the irresistible urge to move the legs. While the name may sound funny, it is a very real disorder.

Russell Katz, M.D., director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research stated:

“People with restless legs syndrome can experience considerable distress from their symptoms. Horizant provides significant help in treating these symptoms.”

The effectiveness of Horizant was studied in two 12-week clinical trials in adults. The trials showed that people taking the medication had an improvement in their RLS symptoms, compared with people taking an inactive pill (placebo).

Symptoms of RLS include having a strong urge to move your legs which you may not be able to resist. The need to move is often accompanied by uncomfortable sensations. Some words used to describe these sensations include: creeping, itching, pulling, creepy-crawly, tugging, or gnawing.

RLS symptoms start or become worse when you are resting. The longer you are resting, the greater the chance the symptoms will occur and the more severe they are likely to be.

Your RLS symptoms get better when you move your legs. The relief can be complete or only partial but generally starts very soon after starting an activity. Relief persists as long as the motor activity continues.

RLS can also cause difficulty in falling or staying asleep which can be one of the chief complaints of the syndrome. A substantial number of people who have RLS also have periodic limb movements of sleep (PLMS). These are jerks that occur every 20 to 30 seconds on and off throughout the night. This can cause partial awakenings that disrupt sleep. Sleep deprivation can seriously impact your work, relationships, and health.

Horizant contains gabapentin enacarbil that becomes gabapentin, a drug used to treat seizures in people with epilepsy, when absorbed into the body. All drugs used to treat epilepsy carry warnings that they may cause suicidal thoughts and actions in a small number of people. Horizant will have the same warning.

The diagnosis of RLS relies essentially on a good medical history and physical examination. Sleep registration in a laboratory (polysomnography) is not necessary for the diagnosis. Peripheral neuropathy, radiculopathy and leg cramps should be considered in the differential diagnosis; in these conditions, pain is often more pronounced than the urge to move.

Akathisia, a side effect of several antipsychotics or antidepressants, is a more constant form of leg restlessness without discomfort. Doppler ultrasound evaluation of the vascular system is essential in all cases to rule out venous disorders which are a common etiology of RLS. A rare syndrome of painful legs and moving toes has been described, with no known cause.

RLS is generally a lifelong condition for which there is no cure. Symptoms may gradually worsen with age, though more slowly for those with the idiopathic form of RLS than for patients who also suffer from an associated medical condition. Nevertheless, current therapies can control the disorder, minimizing symptoms and increasing periods of restful sleep. In addition, some patients have remissions, periods in which symptoms decrease or disappear for days, weeks, or months, although symptoms usually eventually reappear.

Being diagnosed with RLS does not indicate or foreshadow another neurological disease.

Sources: U.S. Food and Drug Adminstration and The RLS Organization

Written by Sy Kraft