Experiencing a muscle twitch can be uncomfortable and irritating. But what causes a muscle twitch, and could it indicate an underlying health condition?
A muscle twitch is an involuntary contraction of the fibers that make up a muscle.
Nerves control muscle fibers. When something stimulates or damages a nerve, it causes the muscle fibers to contract, resulting in a twitch. A person can often see or feel these twitches below the skin.
In this article, we explore the numerous causes of muscle twitches. Most of the reasons for them are harmless though some are more serious. We also discuss how to treat and prevent muscle twitches.
Muscle twitching, also known as fasciculation, has many common causes. These include:
When a person exercises vigorously or for a long period, they may experience muscle twitching.
Research suggests this muscle twitching may happen after exercise for two reasons:
- Firstly, exercise can lead to muscle fatigue. Muscle fatigue triggers twitching and cramping in overworked muscle fibers.
- Secondly, exercise may cause an electrolyte imbalance through sweating. Electrolytes play a role in muscle contraction. An electrolyte loss within muscle fibers may trigger twitching.
The arms and legs are common places to experience muscle twitching that overexertion causes. The most worked muscles are most likely to twitch, which can include the calf, thigh, or biceps, depending on the exercise.
Not getting enough sleep
Brain chemicals, or neurotransmitters, play a role in transmitting information from the brain to the nerves that control muscle contraction.
Sleep deprivation may affect how neurotransmitter receptors work. This means excess neurotransmitters may build up in the brain.
The impact that a lack of sleep has on neurotransmitters function may lead to muscle twitching.
A common place to experience muscle twitching from tiredness is in the eyelid.
Drinking too much coffee, tea, or energy drinks that contain caffeine may cause muscle twitching.
Caffeine is a stimulant. When a person has too much of it, caffeine can stimulate muscle twitching anywhere in the body.
The body needs calcium to support proper muscle function. Having a calcium deficiency may cause muscle twitching. Calcium deficiency is known as hypocalcemia.
People can get calcium from dairy products, soya beans, tofu, nuts, and leafy greens.
Magnesium also plays a role in keeping the nerves and muscles healthy. Magnesium helps to transport calcium across cell membranes to support nerve and muscle function.
Having a magnesium deficiency may cause muscle twitching anywhere in the body, including the face. Magnesium deficiency is known as hypomagnesemia.
Causes of magnesium deficiency include:
- poor diet
- drinking too much alcohol
If people do not address a magnesium deficiency, it may increase their risk of cardiovascular disease.
Vitamin D deficiency
Causes of vitamin D deficiency include lack of exposure to sunshine and poor diet.
Muscle mass is up to 75 percent water. Water also helps to carry nutrients and minerals to muscles to support their function.
When a person does not drink enough water, they may develop dehydration. Having dehydration may cause muscle twitching.
Stress and anxiety
Muscle twitches caused by stress can occur anywhere in the body.
Certain medications can lead to involuntary muscle twitching. This reaction may be a side effect or due to interactions with other drugs.
People can discuss side effects and drug interactions with the doctor when taking a new medication.
Muscle twitching that is not explained by one of the common causes above may indicate an underlying health condition.
Health conditions that can lead to muscle twitching include:
Pinched spinal nerve
A pinched spinal nerve, known as radiculopathy, may cause muscle twitching and spasms. Other symptoms include a tingling or numb feeling in the foot or leg.
A herniated disk can cause a pinched nerve, often the result of trauma. When a disk in the spine is damaged, it may squeeze the root of the corresponding nerve.
Amyotrophic lateral sclerosis
Muscle twitching may be a sign of a degenerative neurological condition called amyotrophic lateral sclerosis (ALS). This is a rare condition.
ALS causes a person's nerve cell function to deteriorate gradually.
Nerve cells, or neurons, control a person's voluntary muscle function, which allows people to move. When a person's neurons stop functioning, their muscles are not able to work properly. This causes:
- muscle weakness
- muscle twitching
- muscle wastage
Over time, a person with ALS may lose the ability to control their movements. This can make walking, talking, eating, and breathing difficult.
Isaacs' syndrome is a neuromuscular condition that may cause muscle twitches.
A person with Issacs' syndrome has overactive peripheral nerve axons. This means that their nerves continuously trigger their muscle fibers. This causes muscle contractions even when someone is resting.
Other symptoms of Isaacs' syndrome include:
- muscle stiffness
- trouble relaxing muscles
Muscle twitching may be a sign of lupus, though this condition is not common.
Lupus is a long-term autoimmune condition where a person's body mistakenly attacks healthy tissue.
Lupus may cause certain muscle groups to become inflamed. This inflammation is called myositis. Muscle twitching is a symptom of myositis.
Rarely, muscle twitching may be a sign of multiple sclerosis (MS). MS is a degenerative condition that affects a person's central nervous symptom.
A common symptom of MS is spasticity. Spasticity is when muscles become stiff and contract involuntarily. Muscle twitching may be a sign of spasticity.
Other symptoms of MS include:
- numbness or tingling
- reduced sexual function
- chronic pain
- changes in cognition
- walking difficulty
- vision problems
A muscle twitch and a muscle spasm are both involuntary contractions of a muscle, although they are not quite the same.
A muscle twitch is a short contraction that may happen repeatedly. It can cause discomfort but is not typically painful.
A muscle spasm is a prolonged contraction that may cause pain. Muscle spasms are also known as muscle cramps. They often happen after exercise.
The doctor may ask a person to discuss when their muscle twitching started, how often it happens, and how it feels. They may also ask about related symptoms.
If the doctor thinks a person's muscle twitching is due to an underlying condition, they will give the individual a series of tests. This may include electromyography to assess muscle and nerve function.
The common causes of muscle twitching are easy to treat and prevent at home through lifestyle changes to keep the nerves and muscles healthy and functioning well. These lifestyle changes include:
- eating a more healthful, balanced diet
- taking dietary supplements to address deficiencies
- exercising moderately, with proper warmups and cooldowns
- reducing caffeine intake
- getting plenty of sleep
- avoiding or managing stress with yoga, mindfulness, or meditation
- staying hydrated
If an underlying health condition is the reason for a person's muscle twitches, the doctor will work with the individual on a treatment plan.
If someone experiences muscle twitching that one of the common causes above cannot easily explain, they should speak to their doctor.
It is also a good idea to speak to the doctor if muscle twitching occurs alongside other, new symptoms.
Muscle twitching has many everyday causes that are not serious. People can easily treat these causes at home and prevent them through specific lifestyle changes.
Some causes of muscle twitching are more serious, but these conditions are mostly rare. The health conditions that may cause muscle twitching are explored above.
If a doctor diagnoses someone with a degenerative condition, such as MS or ALS, they will support them to manage their symptoms. While these conditions have no cure, the right treatment plan can ensure a person maintains a good quality of life.