Eye conditions such as dry eyes or sore, bloodshot eyes can be uncomfortable - but they may also be a sign that something more serious is going on with your sight. Glaucoma can lead to blindness if not treated straight away - and cataracts, which can cause serious vision problems, can be treated easily with minor surgery. Are your eyes trying to tell you something? Here are the warning signs to look out for...

Dry eyes

What is it? Dry eye syndrome is a common condition that occurs when the eyes don't make enough tears or the tears evaporate too quickly, leading to red, swollen and irritated eyes.

Symptoms: Symptoms often include feelings of dryness, grittiness, soreness or a burning sensation that get worse throughout the day. Sometimes eyes may be stuck together when waking and vision temporarily blurred.

Causes: Wearing contact lenses or simply being in a hot or windy climate can cause dry eyes, but they can also occur if you have an underlying medical condition, such as blepharitis (inflammation of the eyelids), or as a side effect of certain medications, including antihistamines, antidepressants, beta-blockers and diuretics. Hormonal changes in women caused by the menopause, pregnancy or even the contraceptive pill can also trigger the condition.

Treatments: Use eye drops to lubricate the eyes, but make sure you choose the right one for you. Lubricant treatments are called artificial tears because they replace the missing water in the tear film and are available without prescription. If you have severely dry eyes and need to use eye drops more than six times a day, then preservative-free drops are best as they prevent harmful bacteria from growing inside the bottle. Oily teardrops are available on prescription and should be used if you have tears that evaporate too quickly. And eye ointments can be used while you're sleeping to make sure eyes stay moist overnight.

If you find eye drops aren't working for you, then it's best to consult a doctor as in severe cases surgery may be necessary to prevent dry eyes reoccurring.

Red eyes

What is it? Red eyes are caused by swollen or dilated blood vessels on the white outer surface of the eye.

Symptoms: Red eyes can be accompanied by eye pain, itching, eye discharge, swollen eyes or visual disturbances such as blurry vision.

Causes: Bloodshot eyes can develop over time or appear suddenly, particularly in response to allergies, over-wearing contact lenses, an eye injury or as a result of conjunctivitis.

Highly contagious, conjunctivitis occurs when the conjunctiva - the thin, normally transparent membrane that covers the eye and lines the eyelids - becomes infected, causing the blood vessels within it to become irritated and swell. If you think you might have conjunctivitis, it's best to visit your doctor as different types of conjunctivitis need different treatments.

Warning! Redness of the eye can sometimes signal a more serious eye condition or disease, such as uveitis, a corneal ulser or glaucoma, all of which are sight-threatening, so always consult your doctor if the condition persists. And if you're a contact lens-wearer, red eyes could be a sign of a serious eye infection, such as keratitis or fungal eye infections, so you should remove your contacts immediately and visit your doctor.

Treatments:If your red eyes are caused by allergies, then anti-histamines can help. If you're a contact lens-wearer, then make sure your lenses and equipment are kept scrupulously clean. And if red eyes persist, consult a doctor immediately.

Vision problems

What is it? Vision problems can include severe or sudden eye pain, recurrent pain in or around the eye, hazy, blurred, or double vision, seeing flashes of light or sudden bright floating spots, seeing rainbows or halos around lights and experiencing a sudden sensitivity to light or change in vision.

Symptoms: You may have vision problems if you find that you're having difficulty walking on irregular or bumpy surfaces, walking hesitantly, using the stairs cautiously or brushing against walls while walking. Other signs can include squinting or tilting the head to the side to focus on an object or having trouble identifying colours.

Treatments: If you find you are experiencing any of the above, visit a doctor and an optician asap as an early diagnosis is essential for treating deteriorating vision.

Glaucoma

What is it? Glaucoma is a name given to a group of eye diseases that can lead to blindness by damaging the optic nerve. Normally the eye continuously produces a fluid, called the aqueous, that drains to maintain healthy eye pressure. With Glaucoma, the drainage canals become blocked and fluid builds up, causing too much pressure within the eye.

Symptoms: Glaucoma is the most common cause of sight loss amongst those of working age and results in peripheral vision loss initially. The effect can be like looking through a tube or into a narrow tunnel and can make it difficult to walk without bumping into objects that are off to the side, near the head, or at foot level. If you have blurred vision, nausea and headaches, or see halos around bright lights, you might have glaucoma.

Treatments: Glaucoma can be treated but not cured. Any damage to the optic nerve cannot be reversed so early detection is essential. Lowering the pressure in the eye quickly can help prevent further damage and peripheral vision loss.

Glaucoma can be treated with eye drops, laser treatment or surgery. If you think you might have Glaucoma, or are suffering any loss of vision at all, contact your doctor immediately.

Cataracts

What is it? Cataracts are the biggest cause of impaired vision around the world. They occur when changes in the lens of the eye cause it to become less transparent, resulting in cloudy or misty vision.

Symptoms: Cataracts usually develop over many years so are more common in older people but they can also occur in children. Symptoms include blurred, cloudy or misty vision or small spots or patches where vision is less clear. Sometimes you may find it more difficult to see in dim or very bright light or find the glare from bright lights uncomfortable. Colours may look faded or less clear and everything may have a yellow or brown tinge. If you wear glasses, you may find that they become less effective over time.

Treatment: If your cataracts aren't too bad, stronger glasses and brighter reading lights may help. However, as cataracts get worse over time, it's likely that you'll eventually need surgery to remove them.This involves removing the cloudy lens through a small incision in your eye and replacing it with a clear, plastic one. In most cases, the procedure is carried out under local anaesthetic (where you're conscious, but the eye is numbed) and you can usually go home the same day.

Almost everyone who has cataract surgery experiences an improvement in their vision, although it can sometimes take a few days or weeks for your vision to settle. You should be able to return to most of your normal activities within about two weeks.