What Causes Vision Blackouts?

The eyes are the organs that play the most important part in how we perceive the world. From time to time, however, we can all suddenly feel our vision blur or black out briefly. Although this often looks temporary and harmless in daily life, a vision blackout can be the warning of certain serious conditions.

What Causes Vision Blackouts?

A blackout most often appears after a sudden movement. When someone stands up quickly from a sitting or lying position, there is a brief fall in blood flow to the brain. That leads to blackouts in the eyes, dizziness and sometimes a feeling of unsteadiness. This situation generally arises from the low blood pressure known as orthostatic hypotension, and it usually settles by itself within a few seconds. If it recurs frequently, however, consulting a doctor is the right thing to do.

Low Blood Pressure

One of the best known causes of vision blackouts is low blood pressure. A sudden fall in blood pressure means that enough oxygen cannot be carried to the brain. In this situation not only blackouts but also symptoms such as weakness, ringing in the ears and cold sweats can be seen. Conversely, high blood pressure can also affect the vessels of the eye and lead to blackouts and blurring. People with blood pressure problems in particular should therefore take vision blackouts seriously.

Low Blood Sugar

Low blood sugar is also among the common causes. Going without food for a long time, skipping meals or a fall in the body's sugar level after intense physical activity can lead to temporary disturbance of vision. This is seen more often in patients with diabetes and can turn into a serious health problem where it is disregarded. Diabetes, and failing to keep blood sugar under control, cause blackouts and even sight loss.

Anaemia

Vision blackouts sometimes appear because of anaemia. When the amount of haemoglobin in the blood falls, enough oxygen cannot be carried to the tissues. As a result, alongside fatigue, pallor, palpitations and shortness of breath, sudden blackouts can be seen. Iron deficiency anaemia in particular is a situation met frequently in young people and in women.

Migraine Attacks

Migraine attacks can also cause vision blackouts. One of the most important signs a migraine gives before it begins is disturbance of vision. A person can experience flashes of light, blurred vision or a brief blackout. This generally runs alongside a headache, while in some people it can be limited to visual signs alone.

Causes Within the Structure of the Eye

Vision blackouts do not always arise from causes outside the eye. Problems relating to the eye's own structure can also produce this complaint. Problems in the retinal layer, blockage in the vessels of the eye or glaucoma can lead to sudden sight loss. Blackouts that develop suddenly in one eye in particular, and that last a long time, may be the warning of a serious problem requiring urgent attention. In situations of that kind an ophthalmologist should be consulted without losing time. Stress, fatigue and severe anxiety are also among the factors that trigger blackouts. Under heavy stress, the hormones released in the body cause the vessels to narrow and affect circulation, which can lead to brief blackouts. This complaint is seen frequently during examination periods, in intense working periods and in people with anxiety disorders.

Side Effects of Medication

The side effects of certain medicines can also lead to vision blackouts. Blood pressure medicines, medicines that regulate heart rhythm and certain sedatives in particular can cause complaints of this kind by affecting blood pressure. If you frequently experience blackouts after taking a medicine, you should always report it to your doctor.

Fluid Loss

Loss of fluid from the body is a simple but important factor that can cause blackouts. Not drinking enough water, sweating heavily, or situations such as diarrhoea and vomiting all lead to fluid loss. This affects circulation and can lead to blackouts and dizziness. Complaints of this kind are experienced more often in summer or after intense exercise.

Heart and Brain Conditions

Sometimes a vision blackout can be the sign of a serious heart or brain condition. Heart rhythm disorders, heart valve disease or blockages in the vessels of the brain can lead to visual disturbance that develops suddenly. If the blackout is accompanied by other signs such as difficulty speaking, weakness in the arms and legs or severe headache, this is an emergency and a doctor should be consulted immediately.

How Are Vision Blackouts Prevented?

To prevent vision blackouts, the underlying cause first has to be known. If the problem is low blood pressure or low blood sugar, eating regularly, not skipping meals and drinking enough fluid all help. Where anaemia is involved, the treatment and diet the doctor recommends should be observed. In blackouts arising from migraine or stress, changes in lifestyle, regular sleep and managing stress all play an important part. Where blackouts recur frequently, last a long time or appear alongside other serious signs, an ophthalmologist or a physician should always be consulted. Although a vision blackout is a temporary situation anyone can experience from time to time, it needs attention when it recurs frequently. It may arise from simple low blood pressure or from hunger, and it may equally be the warning of a more serious condition of the eye or the body. Early diagnosis always brings a great advantage for eye health and for general health. Not taking vision blackouts lightly, not neglecting regular health checks and consulting a specialist when the complaints increase is therefore the right approach. Sight is an extremely important sense for our daily lives and should not be taken lightly.