You suddenly feel something squirming or thumping in your neck, stomach or leg: Is this a blood vessel throbbing or a muscle twitching?

Sometimes, the “crawling” sensation occurs in multiple spots at the same time in a large area such as the back of the legs – with various sections acting up only seconds or minutes apart.

The body is rampant with blood vessels, ranging from those that are microscopic in diameter to the biggest blood vessel in the body: the aorta.

So how can you tell if the “twitching” is actually a throbbing blood vessel vs. a muscle?

“Well, actually, the twitching is due to a nerve misfiring causing the muscle to twitch,” begins Susan L. Besser, MD, with Mercy Medical Center, Baltimore, and Diplomate American Board of Obesity Medicine and board certified by the American Board of Family Medicine.

Dr. Besser explains, “It’s the same mechanism as hiccups, although in that case the misfiring nerve causes the diaphragm (a muscle) to twitch.

“So you really aren’t feeling veins [or blood vessels] at all, but the result of a nerve misfire.”

When I was a child I thought that the squirmy or wriggling sensation (think a worm in the ground) was a vein or artery throbbing, and thought nothing of it. Kids are fearless, aren’t they?

But some adults believe that they’re feeling a blood vessel throbbing or pulsating, when in fact, it’s nothing more than a benign twitching of muscles (fasciculations).

However, let’s face it: It FEELS as though a vein is pulsing or throbbing.

Every day, we can SEE our veins protruding in our hands and feet, and sometimes arms. Imagine if one started throbbing.

What might it feel like? And voila, people draw the conclusion that their veins are pulsating or vibrating.

But rest assured, next time you feel a worm crawling under your skin, this is not a vascular situation. It is muscle fibers misfiring.

By far, the most common causes of twitching muscles are fatigue, physical stress, exercise and anxiety – including anxiety over the fasciculations.

Another cause is magnesium deficiency. “Magnesium is responsible for muscle relaxation, and when you don’t have enough, then its sister-mineral, calcium, causes muscle contraction,” explains Carolyn Dean, MD, ND – Medical Advisory Board Member, Nutritional Magnesium Association at www.nutritionalmagnesium.org.

“Too much calcium and not enough magnesium can cause ongoing twitching,” points out Dr. Dean.

So it’s time to stop fearing that your blood vessels are throbbing, and instead, to realize that you can bet the farm that it’s just some harmless muscle twitching.

susan besser, md

Dr. Besser provides comprehensive primary care for the entire family, treating common and acute primary conditions such as diabetes and hypertension. Her ongoing care and approach allow her the opportunity to provide accurate and critical diagnoses of more complex conditions and disorders.