Eye blinking is a natural, automatic process that occurs in all humans. However, some people experience excessive or abnormal blinking that can disrupt vision or daily life. This excessive blinking is often referred to colloquially as a “tic”, but is it actually a real tic in the medical sense? Let’s explore what’s considered normal blinking, what medical conditions can cause frequent blinking, and whether excess eye blinking should truly be classified as a tic.
What is Normal Eye Blinking?
Blinking is a rapid closing and reopening of the eyelids. It spreads lubricating tears across the surface of the eye to keep it moist. Normal blinking rates vary by individual but average around 15-20 blinks per minute in adults. Blinking increases when the eyes are irritated by dust or other particles and decreases during focused activities like reading. Some key facts about normal eye blinking:
- Blinking helps spread tears, keeping the surface of the eyes properly lubricated.
- The average blink lasts around 100-150 milliseconds.
- Most blinking occurs unconsciously, without us realizing it.
- Reading, computer work, and other visual tasks reduce blinking rate.
- Blinking increases when eyes are irritated, such as by smoke or dust particles.
- On average, adults blink 15-20 times per minute when relaxed.
As long as blink rate is within the normal range and blinking is relatively unconscious, it is not considered problematic or abnormal. However, some conditions can lead to disruptive, excessive blinking.
What Causes Excessive Blinking?
Frequent blinking substantially above the normal baseline can sometimes indicate an underlying medical condition. Possible causes include:
Dry Eye
Dry eye occurs when the eyes do not produce enough tears to stay lubricated. This can cause stinging, burning, and discomfort, leading to an increase in blinking. Dry eyes have many causes, including aging, medications, environmental factors, and autoimmune diseases like Sjogren’s syndrome. Managing dry eye involves using artificial tears and controlling environmental triggers.
Blepharitis
This condition causes inflammation of the eyelids. Blepharitis can make the eyes feel gritty or irritated, triggering extra blinking. Proper eyelid hygiene and sometimes antibiotic eye ointments or pills can help control blepharitis.
Conjunctivitis
Also known as pinkeye, conjunctivitis is inflammation of the conjunctiva, the thin membrane covering the whites of the eyes. Bacterial or viral infections usually cause it, leading to discharge, redness, and eye irritation that provokes frequent blinking. Antibiotic eye drops typically clear up bacterial conjunctivitis.
Foreign Body Sensation
The feeling that something is stuck in the eye, like an eyelash or piece of dirt, can lead to forceful, repetitive blinking. Once the irritant particle is removed, blinking generally returns to normal.
Corneal Abrasions
A corneal abrasion is a scratch or irritation on the surface of the cornea, the clear outer layer protecting the front of the eye. Blinking increases as the eyes try to clean and soothe the abrasion. These injuries are usually minor but quite painful until they heal.
Blepharospasm
This condition causes the muscles around the eyes to contract involuntarily, forcing the eyes to blink or squeeze shut repeatedly. It may occur randomly but can also be triggered by bright light and stress. In severe cases, the spasms can temporarily cause functional blindness. Botulinum toxin injections often successfully control blepharospasm blinking and twitching.
Tourette Syndrome and Other Tic Disorders
Tics are sudden, repetitive movements or vocalizations, such as blinking, twitching, sniffing, or throat-clearing. They are the hallmark symptom of Tourette Syndrome and other chronic tic disorders. Tics often get worse with anxiety and improve with concentration and focus. Neurologic treatment can help manage severe tics that interfere with daily activities.
Seizures
Some types of seizures can manifest with blinking and eye movements like staring, fluttering lids, eyes rolling back, and rapid forced blinking. These ocular signs would be accompanied by other seizure symptoms too. Seizures require urgent medical attention and treatment.
Medications
Certain prescription eye drops, like glaucoma medications, can cause increased blinking, stinging, and irritation. Oral medications with anticholinergic effects, including cold medicines, antihistamines, or muscle relaxants, may also contribute to excessive blinking by drying out the eyes. Adjusting medications under a doctor’s guidance often resolves medication-induced blinking.
Overall, frequent blinking has many potential causes ranging from benign to serious. Dry eyes and eye irritation are the most common causes, but excessive blinking can also result from specific eye conditions, tic disorders, seizures, and side effects of medications.
Is Excessive Blinking a Tic?
By definition, a true tic is an abrupt, uncontrollable movement or vocalization that repeats over and over. It’s a symptom of neurological conditions like Tourette’s syndrome. Tics characteristically get worse with stress and better with focused activity. Medically speaking, just frequent blinking on its own would not constitute having a tic. However, frequent blinking could potentially be one physical tic among multiple if it occurs against the patient’s will as part of a chronic tic disorder.
Some key factors on when excess blinking may signal a tic disorder:
- The blinking is sudden, rapid, repetitive, and feels uncontrollable, rather than just frequent.
- It follows a waxing and waning pattern, worsening with stress.
- It occurs against the person’s will and effort to stop it is only temporarily successful.
- It happens along with other tics like shoulder shrugging, throat clearing, or sniffing.
- It starts in childhood, following the usual onset of chronic tic disorders.
In many cases, frequent blinking has a clear cause like dry eyes or inner eyelid inflammation. But when it has characteristics of an involuntary tic, manifests along with other tics, and starts in childhood, neurological evaluation for a chronic tic disorder would be warranted.
Tics caused by Tourette’s and similar disorders can usually be managed with behavior therapy or medications to help minimize their impact on quality of life. Distinguishing an ocular tic from less concerning causes of extra blinking allows proper treatment to control the tic’s severity.
Medical Causes of Frequent Blinking
Below is a table summarizing some common medical causes of excessive eye blinking:
| Medical Condition | Cause | Symptoms | Treatment |
|---|---|---|---|
| Dry eye syndrome | Insufficient tear production | Irritation, burning, stinging | Artificial tears, managing environmental triggers |
| Blepharitis | Eyelid inflammation | Red, irritated eyes and lids | Eyelid hygiene, antibiotics |
| Conjunctivitis | Infection of the conjunctiva | Red eye, eye discharge | Antibiotic eye drops |
| Foreign body | Sensation of object in eye | Pain, tearing, irritation | Removal of particle |
| Corneal abrasion | Scratch or irritation on surface of eye | Pain, tearing, sensitivity to light | Usually heals on its own |
| Blepharospasm | Involuntary eyelid muscle spasms | Excessive blinking and forced eyelid closure | Botulinum toxin injections |
| Chronic tic disorder | Neurological dysfunction | Sudden, repetitive, involuntary blinking | Behavior therapy, medications |
| Medication side effects | Drugs with anticholinergic effects | Dry, irritated eyes | Adjusting medications |
This table summarizes the most frequent causes, allowing them to be easily compared. In most cases, frequent blinking signals some type of ocular irritation that can be addressed. But when blinking is uncontrollable and accompanies other tics, it may indicate a neurological tic disorder.
When to See a Doctor
In general, see an eye doctor promptly if frequent blinking:
- Comes on suddenly and severely
- Is accompanied by eye pain, swelling, discharge, or light sensitivity
- Persists even when environmental triggers of dryness and irritation are avoided
- Significantly disrupts vision, reading, driving, work, or other activities
- Happens along with uncontrollable movements or vocal tics
- Is worsening and not responsive to over-the-counter eye treatments
An eye doctor can pinpoint the cause through an exam and appropriate diagnostic tests. Often, prompt treatment brings rapid relief and controls troublesome blinking. Seeking medical care is particularly important if blinking is severe and impacting vision and eye health.
Likewise, contact a primary care doctor or neurologist if excessive blinking has characteristics of a motor tic, like being uncontrollable, worsening with stress, and occurring along with other tics. Proper diagnosis is key in such cases to identify any underlying neurological disorder causing tics so that appropriate therapy can be initiated.
Conclusion
In summary, excessive eye blinking is very common and usually results from dry eyes or ocular irritation. Therefore, frequent blinking alone does not inherently constitute a tic in medical terminology. However, when blinking is distinctly involuntary and occurs alongside other physical tics, it may signal a neurological disorder like Tourette’s syndrome. Differentiating benign causes from ocular tics will guide proper treatment. Seeking medical attention is advised if excessive, uncontrollable blinking is disrupting vision and daily life. With evaluation, the cause can be determined and specific relief provided, managing even severe blinking issues.