Home Symptoms Red eyes: causes, diagnosis, treatment

Red eyes: causes, diagnosis, treatment

by Josephine Andrews
Published: Last Updated on 368 views

Red eyes are a mostly harmless symptom. Lifestyle is often the reason when the whites of the eyes are completely or partially red – such as lack of sleep. However, various diseases can also cause reddening of the eyes. Read here why the eyes can be red and what you can do about it!

quick overview

  • Causes : e.g. dry eyes, conjunctivitis (e.g. as a result of an allergy), corneal inflammation, iris inflammation, glaucoma, broken capillaries in the eye , lack of sleep, dry room air, dust or cigarette smoke, trauma, UV rays, drafts, toxins, cosmetics, contact lenses ; reddened eyelids, among other things, with chalazion and barleycorn
  • When to the doctor? If accompanying symptoms occur such as severe eye pain, fever, nausea and vomiting, loss of visual acuity, visual disturbances, rash and open injuries to the eye.
  • What helps against red eyes? Depending on the cause, for example moisturizing eye drops, antiallergic medication (antihistamines), antibiotics, antivirals , cortisone, treatment of any underlying diseases
  • You can do this yourself : eg get enough sleep, avoid tobacco smoke, drafts and UV radiation, avoid allergy triggers if possible, avoid contact lenses, do relaxation exercises for the eyes, cold compresses

Red eyes: causes

Almost everyone has red eyes at least once in their life. Bloodshot eyes can look quite dangerous. The reddening of the eyes is caused by the fact that the blood vessels on the surface of the eye are dilated and are supplied with more blood.

In most cases, there is a harmless cause behind it. For example, after a night of drinking in a smoky room, red veins are often visible in the eye. With enough sleep and avoidance of smoky air, this reddening of the eyes generally disappears on its own. Sometimes red eyes are also caused by (serious) illnesses.

Here is an overview of common factors that can cause red and irritated eyes:

  • lack of sleep
  • cigarette smoke
  • Dry room air
  • Dust
  • Air conditioning or draft
  • UV rays
  • Eye irritation from contact lenses or cosmetic products

Conditions that can cause red eyes include:

  • Inflammation of the conjunctiva (conjunctivitis), for example allergic conjunctivitis
  • Inflammation of the cornea (keratitis)
  • Inflammation of the middle part of the eye membrane in the front part (anterior uveitis like iris inflammation)
  • Inflammation of the layer of connective tissue between the dermis and conjunctiva (episcleritis)
  • Inflammation of the dermis (scleritis)
  • Inflammation of the eyelids (blepharitis)
  • Glaucoma or acute glaucoma attack (glaucoma)
  • Sjogren’s Syndrome
  • eye herpes
  • tumors
  • Ophthalmorosacea (form of rosacea that affects the eyes)
  • Atopic diseases (e.g. neurodermatitis)

Blunt trauma such as a blow to the eye, severe rubbing, or eye surgery also cause red eyes.

A red spot in the eye is usually an area of ​​bleeding under the conjunctiva, called hyposphagma .

Red Eye & Allergy

Red eyes are a common symptom of an allergy. The conjunctiva contains many immune cells that can overreact to normally harmless substances such as pollen, mold spores or house dust mite faeces. They then release chemical substances that trigger inflammatory processes in the eye – allergic conjunctivitis (allergic conjunctivitis) develops. A distinction is made between three forms:

  • seasonal allergic conjunctivitis ( hay fever ): It is triggered by the pollen of various plants (trees, grasses, etc.). The symptoms, such as red, burning, itchy eyes and a runny or stuffy nose, occur during the flowering period of the plants to which the person is allergic.
  • Atopic conjunctivitis : It is an allergic reaction of the eyes that can occur all year round: Red, burning and itchy eyes are caused by house dust mites , animal dander (e.g. from cats ) or other non-seasonal allergens.
  • Vernal keratoconjunctivitis : It too is probably the result of an eye allergy. It is a combined conjunctivitis and corneal inflammation that occurs primarily in spring. It primarily affects male children and adolescents with eczema, asthma or seasonal allergies. Inflamed eyes with red eyes are typical symptoms.

Conjunctivitis – whether allergic or otherwise – is one of the most common reasons for red eyes.

Contact dermatitis (contact allergy) can also be responsible for reddened eyes or reddened skin around the eyes. For example, some people are allergic to eye drops, face creams, make-up or other cosmetic products and develop redness and/or a rash on the eye. Itching, swelling of the eyelids and scaly skin changes are also possible.

Red eyelids

Red eyelids with sticky eyelashes are a typical symptom of eyelid inflammation ( blepharitis ). The conjunctiva is then often slightly reddened. The cause of the inflammation is clogged sebaceous glands on the edge of the eyelid. People who suffer from excessive sebum production and thus often acne, neurodermatitis or rosacea are susceptible to blepharitis.

Swollen, red eyelids are also found with chalazion and stye : The chalazion is also based on a blocked sebaceous gland . However, the resulting inflammation is limited to a narrow part of the eyelid – a painless, reddened swelling forms on the edge of the eyelid. On the other hand, the stye appears as a painful, reddened swelling on the edge of the eyelid, caused by bacterial inflammation of a sebaceous gland.


Do you have a single red eye? The cause is then often a burst blood vessel under the conjunctiva. Doctors speak of hyposphagma. The subconjunctival hemorrhage is visible as a sharply defined red spot in the eye. This can look frightening, but is usually nothing to worry about. Broken veins in the eye heal on their own.

A hyposphagma can occur, for example, through strong rubbing of the eye. But even without such mechanical irritation, an eye can be red – in people with high blood pressure, a blood vessel in the eye can burst on its own, especially if the patient is taking medication to thin the blood (oral anticoagulants).

If you often have burst veins in your eyes, you should have your blood pressure checked by a doctor.

Red eyes: accompanying symptoms

Red eyes often do not appear alone. Common accompanying symptoms include:

The combination of different symptoms often gives clues to the cause. For example, red, burning eyes can be caused by a lot of screen work or eye irritation from contact lenses or smoke, among other things. When an eye is red and itchy, conjunctivitis is often present.

Red eyes: when to see a doctor?

If redness of the eyes is accompanied by one or more of the following symptoms, a doctor’s visit is necessary:

  • sudden severe eye pain
  • nausea and vomiting
  • rash on the face (especially around the eyes or on the tip of the nose)
  • decreased visual acuity
  • visual disturbances
  • open wound on the cornea
  • Fever

Even if the red eyes are caused by a foreign body in the eye (metal splinters, chemicals, etc.), you should see a doctor immediately.

Red Eyes: Examinations & Diagnosis

First, the doctor will take your medical history (anamnesis) in a detailed discussion with you. This is followed by various examinations to clarify the red eyes (and possibly other symptoms).


During the medical history, the doctor may ask you the following questions, for example:

  • How long has the eye redness existed?
  • Have you ever had red eyes?
  • Do you have any other symptoms in addition to the reddening of the eyes (such as eye pain, itching, etc., fever, headache, etc.)?
  • Is there more secretion from the eyes?
  • Has your eyesight changed?
  • Is there an eye injury?
  • Do you wear contact lenses?
  • Did you get foreign bodies or other substances in your eyes (dust, splinters, etc.)?
  • Do you take any medicine?
  • Are you allergic?


During the subsequent physical examination , the doctor takes a closer look at the area around the eyes. Among other things, he pays attention to skin changes, swelling and other abnormalities. Depending on what other symptoms you have besides the red eyes, he can also examine the skin on the rest of your body or measure your body temperature, for example.

Various examinations also help to find out the reason for the reddening of the eyes. The doctor checks the size of the pupil, the reaction of the eyes to incident light and eye movements. The following investigations may also be informative:

  • eye test
  • Slit lamp examination (to assess different parts of the eye)
  • Examination of the tear fluid
  • allergy test
  • Swab from the eye (if an infectious cause is suspected)

Red eyes: treatment

The treatment of red eyes always depends on the cause. The redness of the eyes themselves usually does not require any treatment. It usually goes away on its own when the cause subsides or is eliminated.

Reddened, dry eyes can be treated with

If the cause of red eyes is bacterial conjunctivitis , eye drops or ointments with added antibiotics often help. In certain cases, it may also be necessary to take antibiotics, for example in the case of conjunctivitis as a result of a chlamydia infection. Viral conjunctivitis can only be treated symptomatically, for example with artificial tears and cortisone eye drops.

However, if herpes viruses are the reason why the eyes are red and inflamed ( eye herpes ), causal treatment with antiviral agents, so-called antivirals, is possible. For this purpose, the doctor can prescribe eye drops with the active ingredient aciclovir, for example.

If an allergy is responsible for an inflamed conjunctiva (allergic conjunctivitis), the allergy trigger should be avoided if possible. In addition, antiallergic agents (antihistamines) in the form of eye drops or tablets can relieve reddened eyes and any other allergy symptoms. Eye drops containing cortisone can be useful for severe allergies.

Red eyes: You can do this yourself

You too can do something to prevent red eyes. Getting enough sleep drives away red eyes caused by short nights. Avoid tobacco smoke, drafts or strong sunlight if this is the cause of the reddened eyes.

For reddened, dry eyes, there are various lubricating eye drops that are over the counter. Talk to a doctor about using them first. Maybe there is a disease that needs treatment behind the dry eyes.

If contact lenses cause red, irritated eyes, you should not wear them for a few days and put on glasses instead. The stressed eyes can then calm down. You may also need other contact lenses. Talk to your ophthalmologist or optician about it.

If the reddening of the eyes is caused by mascara, eye cream or other cosmetic products, the rule is: hands off! It is better to switch to a better tolerated product.

Do you have red, dry eyes from staring at a screen (computer, TV, etc.) for too long? Then relaxation exercises for the eyes are a good idea. Some examples:

  • Consciously look closely at things at different distances (keep your eyes sharp!).
  • Occasionally cover your eyes with your hands and let them rest for a few minutes.
  • Place your thumbs on your temples and use your index fingers to massage the top of your eye socket (from the bridge of your nose outward).
  • You should often close your eyes for a few seconds while working on the screen. You can also try to type a few sentences “blind”.

If contact with chemicals (e.g. a splash of cleaning agent) has caused a red eye or red eyes, it usually makes sense to rinse the eyes with clear water (unless caustic lime has gotten into the eyes – rinsing out can then worsen the chemical burn! ). After that, find a species immediately. Consider bringing the chemical with you so that he can adjust the treatment accordingly if necessary.

If a solid foreign body such as dust or metal splinters causes the redness of the eyes, first aid measures and then a visit to the doctor are indicated.

Home remedies for red eyes

Irritated, red eyes can often be soothed with cool compresses. To do this, dip clean cotton towels in cold water, wring them out and then place them on the red eye(s). Instead of water, you can also use cooled chamomile , calendula or sage tea . Leave the cool compress on your eyes for as long as is comfortable.

Instead of damp cotton cloths, you can also put a seed pillow (e.g. cherry pit pillow) that you have previously chilled in the freezer on your eyes. Or you can use cool packs. Do not put this directly on the reddened eyes, but first wrap them in a cotton cloth.

Home remedies have their limits. If the symptoms persist over a longer period of time, do not get better or even get worse, you should always consult a doctor.

You may also like

Leave a Comment