Light sensitivity: what causes light deficiency (photophobia)?

Sensitivity to light can be a symptom of a problem of a nervous nature, a disturbance in the function or structure of the eye. In some cases, it is a symptom of some more serious infectious diseases.

Professionally, this condition is called photophobia.

The person is more sensitive to light and this makes him uncomfortable. For example, it is also difficult to move between differently lit rooms. Especially if he goes from a less illuminated interior to the exterior.

Sometimes light deficiency can also have external causes.

Very often, people who spend most of their time doing office work in darker rooms suffer from excessive sensitivity to light. Light blindness also occurs if a person works for a long time with computer equipment and monitors.

With dry eye syndrome, other symptoms such as eye fatigue or eye pain or itching and visual impairment can also be associated.

Dry eye affects approximately 20% of the population today and up to 30% of post-menopausal women.

Read also: Interesting information about dry eye syndrome.

The cause is in the eye

Most often, light sensitivity is generally considered to be a manifestation of some eye defect or disease.

It is a symptom of various inflammatory diseases of the eye, such as inflammation of the iris (iritis), cornea (keratitis), retina (retinitis) or conjunctiva (conjunctivitis).

Conjunctivitis is very common. The conjunctiva is a membrane made up of mucous membrane that covers the eye and the white of the eye from the front to the edge of the cornea. Typically, this inflammation is manifested by a cutting sensation in the eye, increased tearing and pain in the affected eye. In most cases, the inflammation affects only one eye.

Often, a cataract can be behind the photophobia. Most cases where there is sensitivity to light as a symptom of cataract are in cataracts. This affects the lens of the eye. It becomes cloudy and the person experiences a kind of blurred vision and a general deterioration of vision.

Typically, visual acuity also decreases, especially in the distance. Often, the glaucoma in eye problems is associated with other symptoms, such as impaired vision and focusing even at close range and pressure or pain in the eye.

Diseases of the nervous system

In addition to eye disease, light sensitivity can be caused by a problem in the nervous system. This can cause inflammation of the brain and meninges, as well as bleeding or a tumour.

Irritation of the meninges occurs, resulting in meningeal symptoms or even meningeal syndrome.

Symptoms include:

• headache
• a feeling of nausea, later vomiting
• sensitivity to light (photophobia)
• hypersensitivity to noise (phonophobia)
• stiffness of the neck muscles, otherwise also neck opposition

Meningitis, caused by meningococcus type B and C, causes meningeal irritation. It is a disease with sudden onset, rapid onset and rapid course, within hours. In children and the elderly, it is often the cause of death.

In meningitis, there are headaches, vomiting and light-headedness. Fever, even up to 40 °C, and small, dot-like blood bruises on the skin (so-called petechiae) are associated.

At a later stage, the disease may result in a disturbance of consciousness, convulsions of the body. Later complications may include epilepsy, but also hearing loss.

Inflammation of the brain is caused by viruses or bacteria. For example, in tick-borne encephalitis, the meninges and brain become inflamed by transmission of a viral infection from a tick.

Read also:
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Lyme disease is one of the infectious diseases that also affect the brain and central nervous system. The disease is of bacterial origin and is also transmitted by ticks.

The infection also affects the skin, joints and heart. The disease is very lengthy and the person is tired and suffers from headaches. Another cause can be malaria, which is also an infectious disease. Even with this disease, the person is sensitive to light.

Measles is also an infectious disease. A skin rash is typical and the disease is very infectious. At the same time, there is also photophobia.

Other diseases of the nervous system can be manifested by sensitivity to light. For example, migraine is characterised by a severe headache. The person is sensitive to light during this pain.

Other causes of light sensitivity

As a non-characteristic symptom, photophobia can also occur in hyperthyroidism, which is a disease of the thyroid gland. In this disease, there is an overproduction of hormones. In connection with this, Basedow's disease can also occur, which causes the eye to protrude from the orbit (exophthalmos) and sometimes double vision and sensitivity to light in the affected person.

Hypersensitivity to light is reported in the case of a disease called systemic lupus erythematosus or vitamin B3 deficiency. It is one of the symptoms of rabies. People who suffer from albinism may also be sensitive to light.

If photophobia occurs without obvious causes, it is always best to see a doctor for a diagnosis.