The Red Eye
Contents of this Page
There are numerous conditions which can cause eye redness, and nearly
any condition causing symptoms of discomfort will also lead to eye redness.
Redness usually specifically refers to the "white of the eye."
Redness here can be due to engorged blood vessels on the surface of
the eye, or due to hemorrhage on the surface. The location and pattern
of redness may be important to making a diagnosis, as may be any associated
symptoms and findings.
This page discusses a few causes of eye redness which
are not discussed elsewhere. There are also links to other Symptom and
Diagnosis pages based on other symptoms in addition to the redness.
For eye anatomy explanations, go to
- Conjunctivitis, or "pink eye", is an infection of the
lining over the sclera (the "white of the eye"). This lining
is the conjunctiva, and it also lines the inside of the eyelids. The
infection is typically either caused by a virus, or by bacteria.
Viral conjunctivitis is common in adults, and is extremely contagious
(even with indirect contact). Sometimes it may occur with the common
cold. The eyes become injected and itch. There may be a watery or
mucoid discharge, and the lids may swell. Both eyes are usually
affected. Treatment is to reduce symptoms, since antivirals are
not available. It usually runs its course in about 2 weeks. Care
must be taken to wash the hands after touching the eyes.
Bacterial conjunctivits is more common in children. While also
contagious, it requires more direct contact for spread than a viral
infection. Eye redness, lid swelling, and a heavy pus-like discharge
are common. Treatment with antibiotic eyedrops, ointments, and sometimes
even pills by mouth are necessary for treatment. Cultures may be
taken to determine the bacteria involved and appropriate antibiotics.
- A subconjunctival hemorrhage usually appears as a sudden, spontaneous,
bright red patch on the surface of the eye. This occurs when a small
blood vessel breaks in the lining over the eye (the conjunctiva).
It is usually otherwise painless, and the vision is not affected.
The redness can be quite dramatic. This can occur spontaneously, or
after direct trauma, sneezing or coughing, or straining. High blood
pressure is another possible cause. The redness usually disappears
over a one week period.
- Episcleritis is an inflammation of the episclera, which is a fibrous
layer between the white wall of the eye (the sclera) and the lining
of the eye (the conjunctiva). With this condition, there is a patch
of injected blood vessels on the surface of the eye (only a part of
the eye is red). It may be associated with mild irritation, or sometimes
iritis. The condition may resolve without treatment, but it also can
recur, and may affect both eyes. It sometimes is associated with gout.
Many prescription and non-prescription eyedrops can create ocular
irritation or allergy, especially if used for a long period of time.
Over-the-counter eyedrops such as artificial tears, allergy eyedrops,
and contact lens solutions all contain preservatives unless the bottle
specifically states "preservative free". These preservatives
can commonly cause eye irritation and redness, if the user is sensitive
to that preservative.
Prescription antibiotic eyedrops can be effective at treating infection,
but they can also be quite irritating to the eye and may cause prolonged
irritation and redness. This may lead to confusion as to whether
or not the infection has really been treated. Steroid eyedrops usually
are not particularly irritating. A few prescription allergy eyedrops
are known to cause some eye redness and burning on installation.
Vasoconstricting or decongestant eyedrops ("get the red out"
drops) simply blanch out blood vessels on the eye surface, concealing
redness. If these eyedrops are used frequently to mask redness,
there may be a rebound redness when the drops are discontinued.
This may lead to more usage of the eyedrop to conceal the worsening
A pinguecula is an
extremely common lesion which consists of a yellow-white deposit on the bulbar
conjunctiva adjacent to the nasal or temporal aspect of the limbus Histological
examination shows degeneration of the Collagen fibres of the conjunctival stroma,
thinning of the overlying epithelium and occasionally calcification. Some
pingueculae may enlarge very slowly but surgical excision is seldom required.
A pterygium is a non-cancerous growth of the conjunctiva onto the cornea. It may
start as a "pingueculum", which is a small lump of tissue located on
either side of the cornea on the sclera. A pterygium has a "head",
which may progressively cover the cornea, and a "body" which extends
toward the corner of the eye (usually the inside corner). Often the
"body" of a pterygium may appear red, with noticeable blood vessels.
A pterygium which progressively moves toward the pupil may need
to be surgically removed in order to prevent the vision from being
affected. Redness and irritation from a pterygium can be managed
with artificial tears, and with other prescription eyedrops.
Pterygia seem to occur more frequently in people who spent much
time outside, and is especially common in the southern lattitudes.
If they need to be removed, there is a possibility of recurrence.
problems - usually with itching and irritation.
- itching, burning, eyelid irritation.
(infection) of eyelid skin - eyelid swelling, tenderness.
lens related problems - may have pain, scratchy sensation.
abrasion - pain, tearing, sensation that something is in
Dry eye - irritation, scratchy sensation, sometimes tearing.
(out-turning) of eyelid - scratchy sensation, pain, tearing.
(in-turning) of eyelid - scratchy sensation, pain, tearing
(acute) - pain, blurred vision.
Iritis - pain, sensitivity to light, blurred vision.
- sensation that something is in eye, burning, itching.
- pain, blurred vision.
related eye disease - scratchy sensation, double or blurred
vision, protruding eyes.
(in-turning of eyelashes) - scratchy sensation, pain, tearing.