What is benign fasciculation syndrome?

by Margo White / 07 February, 2013
Involuntary muscle twitching may cause anxiety, but is rarely cause for concern.
What is benign fasciculation syndrome?

We’re often, quite rightly, cautioned against using the internet for a medical self-diagnosis, as it’s likely to present us with the worst-case scenario. On the other hand, Google can send us to places where even hypochondriacs will be reassured there is nothing wrong with them.

This is the experience of Angela Woods who, after an onset of twitching in her calf muscles and one hand, googled “twitching muscles” and was persuaded that she had a degenerative neurological disease. That was before she came across benign fasciculation syndrome and the website aboutbfs.com, and identified with and was consoled by both the psychological and physiological symptoms being described.

“It seems everybody there has a background of hypochondria, stress and anxiety,” she says, explaining that her twitching coincided with a stressful time and that she’s always had a tendency to hypochondria. “If you read the forums, they’ll tell you there’s nothing to worry about. And also they’ll tell you to get away from the computer.”

But what is benign fasciculation syndrome, and can Woods trust aboutbfs.com? Fasciculations are small involuntary muscle twitches. Sometimes they can be symptomatic of a serious disease. Mostly, they are something people commonly get and generally don’t even notice. Revealingly, however, they are most likely to bother people with some medical training. “Such as medical students, shortly after having a lecture on motor neurone disease,” says Chris Lynch, a neurologist at Waikato Hospital and senior lecturer at Waikato Clinical School, who adds that GPs are also susceptible.

There’s not a lot about benign fasciculation syndrome in the medical literature, and neurologists might be more likely to talk about benign fasciculation than benign fasciculation syndrome. Is it actually a disorder, or just a lot of twitching? “That’s more of a philosophical question, which you can’t really answer,” says Graeme Hammond-Tooke, clinical neurologist and professor of medicine at the Dunedin School of Medicine. “It doesn’t really cause you harm or discomfort, so it’s not really a dis order. What causes it is a bit uncertain – there might be something funny going on in the nerve terminals. But it would usually have to be something that is unpleasant and inconvenienced you in some way before you’d call it a disease.”

In short, benign fasciculation syndrome is real, it can be annoying, but it’s nothing serious – at least once you know that’s what you have. “I suppose it’s an issue, because if it’s not benign, it’s usually motor neurone disease, which is a terrible disease,” says Hammond-Tooke. “But most people don’t know about motor neurone disease so don’t think about it.” Except medical students and GPs or people exposed to those with such diseases, for whom the twitches can cause considerable distress.

Benign fasciculations most commonly occur in the calf muscles, but also around the eye and the forearm. It’s difficult to differentiate between those caused by a neuronal disease or by benign twitching, but if something serious is going on, the twitching is likely to be accompanied by other symptoms. “Such as loss of muscle function, or muscle structure over a short period of time,” says Lynch. “Or losing the ability to do something with your hand or your foot, maybe stumbling a bit – not in a way that one expects with age or loss of fitness.”

If you have symptoms other than muscle twitching, it might be worth getting checked out, if only to calm your nerves. Neurologists will usually be able to tell through a clinical evaluation whether the fasciculations are benign, and won’t need to do expensive tests. If they have any concerns or doubts, they can also use electromyography (EMG), a technique that detects the electrical signals generated by muscle cells and will reveal any abnormal activity.

But as Lynch notes, patients tend to have not only symptoms, but also a great deal of anxiety, and some won’t be reassured without tangible proof that they’re okay.

“If they are paralysed with fear and wanted the test, we might go down that path. But in most instances that I can recall, because of the character and distribution of the fasciculations, I didn’t need to do any tests. I’ve been able to say, ‘I think it’s benign; we can afford to wait.’”

Health briefs


Taking an active approach to life can be as good for us as going to the gym, and people can easily meet physical-activity guidelines by incorporating short bouts of exercise into their day, according to research published in the American Journal of Health Promotion. The researchers note doing so is more cost-effective than joining the gym, as people are more likely to stick with the programme.


Researchers have identified the neurons that detect the gentle stroking of hairy skin that seem to promote a state of well-being when activated, at least in mice. The researchers used a custom-designed brush to stroke the rodent’s hairy hind limbs, and used calcium imaging to show that the responding cells contained a rare group of unmyelinated sensory neurons, and activating them is rewarding and anxiety-reducing. Further studies are needed to see if they also exist in humans.


Although US research has shown that spending a lot of time in childcare leads to bad behaviour, a study by the Norwegian Institute of Public Health and the Norwegian Centre for Child Behavioural Development shows that it doesn’t. The study used data from 72,000 mothers and their children, looked at obedience and aggression in children at 18 and 36 months and the amount of time they spent in childcare. That the results conflicted with US research could be put down to the difference between US and Norwegian centre-based childcare.
MostReadArticlesCollectionWidget - Most Read - Used in articles
AdvertModule - Advert - M-Rec / Halfpage


How empathy can make the world a worse place
71431 2017-04-24 00:00:00Z Social issues

How empathy can make the world a worse place

by Catherine Woulfe

Many of us think that high empathy makes you a good person, but giving in to this “gut wrench” can make the world worse, says a Yale psychologist.

Read more
For the Fallen: Remembering those lost to war
71473 2017-04-24 00:00:00Z History

For the Fallen: Remembering those lost to war

by Fiona Terry

Every day before sundown, a Last Post ceremony is held at the National War Memorial in Wellington, to remember those lost in World War I.

Read more
Film review: Ghost in the Shell
71490 2017-04-24 00:00:00Z Movies

Film review: Ghost in the Shell

by Russell Baillie

Nothing dates faster than a past idea of the future.

Read more
The rate of technological change is now exceeding our ability to adapt
71303 2017-04-24 00:00:00Z Technology

The rate of technological change is now exceeding …

by Peter Griffin

A decade on from the revolution of 2007, the pace and rate of change are exceeding our capacity to adapt to new technologies.

Read more
Government tests electric limo for Crown fleet
71520 2017-04-24 00:00:00Z Technology

Government tests electric limo for Crown fleet

by Benedict Collins

An electric-hybrid limousine is being put through its paces to see whether it's up to the job of transporting politicians and VIPs around the country.

Read more
What growing antibiotic resistance means for livestock and the environment
71360 2017-04-23 00:00:00Z Social issues

What growing antibiotic resistance means for lives…

by Sally Blundell

Animals kept in close proximity, like battery chickens, are at risk of infectious disease outbreaks that require antibiotic use.

Read more
The little-known story of Ernest Rutherford's secret anti-submarine work in WWI
71418 2017-04-23 00:00:00Z History

The little-known story of Ernest Rutherford's secr…

by Frank Duffield

Famous for his work splitting the atom, Ernest Rutherford also distinguished himself in secret anti-submarine research that helped the Allies win WWI.

Read more
Book review: Larchfield by Polly Clark
71160 2017-04-23 00:00:00Z Books

Book review: Larchfield by Polly Clark

by Nicholas Reid

Poet WH Auden stars in time-hurdling novel – as a life coach to a lonely mum.

Read more