Benign fasciculation syndrome

Animated image of BFS in the upper eyelid of a 19 year old male. Symptoms subsided several days later.

Benign fasciculation syndrome (BFS) is a neurological disorder characterized by fasciculation (twitching) of various voluntary muscles in the body. The twitching can occur in any voluntary muscle group but is most common in the eyelids, arms, legs, and feet. Even the tongue may be affected. The twitching may be occasional or may go on nearly continuously. Any intentional movement of the involved muscle causes the fasciculations to cease immediately, but they may return once the muscle is at rest again.

Common features

The main symptom of benign fasciculation syndrome usually is focal or widespread involuntary muscle activity (twitching). In addition to the twitching, some sufferers experience pain, generalized fatigue, exercise intolerance, globus sensations, muscle cramping, and/or paraesthesias.

Another common feature of the disorder, when seen by physicians, is an increase in the patient's level of anxiety, especially health-related anxiety^{[citation needed]}. It's not uncommon for the patient to fixate on ALS, MS, ME, Parkinson's, vCJD, Wilson's Disease, Dystonia or some other serious neurological disorder, refusing to believe the BFS diagnosis^{[citation needed]}. Many health anxious people are greatly helped by the discussion websites (see External Links section) containing a wealth of knowledge on the conditions and symptoms discussed by long-term suffers willing to help and calm the worries of people mistakenly fearful of having one of the more serious disorders^{[citation needed]}.

Causes

Though twitching is sometimes a symptom of serious diseases such as spinal injury, muscular dystrophy, Lyme Disease, multiple sclerosis or amyotrophic lateral sclerosis (ALS), it is much more often due to more benign causes (BFS, over-exertion, etc.), and virtually everyone will experience some episodes of benign fasciculation during their lifetime.

The precise cause of BFS is unknown, and, in fact, it's not known if it's a disease of the motor nerves, the muscles, or the neuromuscular junction. Mitsikostas et al. found that fasciculations "were slightly correlated to the body weight and height and to the anxiety level" in normal subjects. Another factor that seems to be common in many cases is a history of regular strenuous exercise.^{[citation needed]} Attention deficit disorder (or drugs used to treat it) and/or a related disorder may be a contributing factor,^{[citation needed]} and people with essential tremor appear to have a greater than normal likelihood of developing BFS.^{[citation needed]} In addition, there are likely other genetic and environmental factors that make the patient more susceptible to BFS.^{[citation needed]}

There are some intriguing similarities between BFS and chronic organophosphate poisoning, but these similarities have not been explored. It may be that chronically elevated levels of stress hormones in the body cause symptoms similar to those caused by organophosphates.

BFS can also be attributed to long term use of anticholinergics such as diphenhydramine and opiates such as morphine, but the latter case is usually when withdrawal symptoms are present.

Magnesium Deficiency can cause both fasciculations and anxiety.

Gluten sensitivity has never been associated with BFS.

Diagnosis

Diagnosis of BFS is a "diagnosis of exclusion," in other words, other likely causes for the twitching (mostly forms of neuropathy, such as borreliosis (Lyme disease) neuropathy, motor neuron diseases such as ALS, etc.) must be eliminated before BFS can be assumed. An important diagnostic tool here is the (EMG). Since BFS appears to cause no actual nerve damage (at least as seen on the EMG), a completely normal EMG (or one where the only abnormality seen is fasciculations) largely eliminates more serious disorders and strongly suggests BFS.

Unlike ALS, BFS symptoms are usually present when the muscle is at rest, and are not accompanied by severe muscle weakness.

Another abnormality commonly found upon clinical examination is a brisk reflex action known as hyperreflexia. Standard laboratory tests are unremarkable. According to neurologist John C. Kincaid:

In the absence of clinical and electromyographic findings of neurogenic disease, the diagnosis of benign fasciculations is made. I suggest that patients like this be followed for a year or longer with clinical and electromyographic exams at about 6-month intervals before one becomes secure in the diagnosis that the fasciculations are truly benign. My approach to treating fasciculations that appear to be benign is to first reassure the patient that no ominous disease seems to be present.

Treatment

Some degree of control of the fasciculations may be achieved with the same medication used to treat essential tremor (beta-blockers and anti-seizure drugs). However, often the most effective approach to treatment is to treat any accompanying anxiety. No drugs, supplements, or other treatments have been found that completely control the symptoms. Cannabis has been effective at mitigating the severity of the symptoms with minimal to no side effects, particularly Indica strains that are high in the non-psychoactive cannabidiol (CBD).

In many cases, the severity of BFS symptoms can be significantly reduced through a proactive approach to decrease the overall daily stress. Common ways to reduce stress include: exercising more, sleeping more, working less, meditation, and eliminating all forms of dietary caffeine (e.g. coffee, chocolate, cola, and certain over-the counter medications).

Opiate therapy with drugs such as oxycodone can reduce symptoms of pain and nerve activity significantly. Since BFS is a form of peripheral nerve hyper-excitability, the problem lies in the potassium channels. The potassium channel along with the sodium channel are two of the chemical mechanisms within the nerve that are involved with the production of nerve cell signals. Normally these channels function in equilibrium, but in the case of BFS there is a glitch in the potassium channel.^{[citation needed]} Oxycodone works by rectifying potassium channels and results in reduced neuronal excitability.^{[citation needed]} Oxycodone is a controlled substance and can lead to addiction and dependency but when taken properly it can be safe and very effective in treating BFS pain, parathesia, and globus sensation^{[citation needed]}

See also

• Fasciculation
• Neuromyotonia
• Cramp fasciculation syndrome