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" What is it used for?  Dry eye conditions. Dryness of the eye surface (cornea) and lining of the eye socket (conjunctiva) due to reduced tear production (keratoconjunctivitis sicca).   How does it work? Sno tears eye drops contain the active ingredient polyvinyl alcohol, which is a type of medicine known as an eye lubricant. It is used for the treatment of the symptoms of dry eye (such as soreness, burning, irritation or dryness) caused by your eye not producing enough tears to keep the eye wet.  Tears consist of a slightly alkaline fluid that is spread across the eye by blinking. The tear film is kept stable by mucin which is secreted by a thin membrane covering the front of the eye, called the conjunctiva. Dry eyes result from a reduced production of tears, a reduced production of mucin by the conjunctiva, or increased evaporation of tears from the surface of the eye. Reduced tear production is common in elderly people, but can also occur in some diseases or as a side effect of certain types of medicines. Increased evaporation of tears can occur in thyroid disease, or from disorders affecting the eyelid or other parts of the eye. These problems make the film of tears that covers the eye become unstable, allowing it to break into dry spots between blinks, rather than remaining spread across the eye to keep it moist. Polyvinyl alcohol works by decreasing the surface tension of the tears so that they spread more easily over the surface of the eye and don&amp;#039;t break into dry spots. It also has properties similar to the natural mucin produced by the conjunctiva, which soothes and lubricates the eye and enhances the stability of the tear film.   Warning!  This medicine is for use in the eyes only and must not be taken by mouth. When use in the eyes you should take care not to touch your eye or any surface with the dropper tip, to avoid contaminating the eye drops. These eye drops contain the preservative benzalkonium chloride. As this may be absorbed by soft contact lenses these drops should not be used by people who wear this kind of lenses. Preservative-free drops are available and your pharmacist should be able to recommend a suitable one. This medicine may cause your vision to blur temporarily after you have applied it into your eye. Do not drive or operate machinery until this has worn off. Sno tears eye drops should discarded four weeks after the first opening. You may find it helpful to write the date of opening on the pack. Dispose of them carefully, preferably by returning them to your pharmacy.   Not to be used in  Known sensitivity or allergy to any ingredient.   This medicine should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.   Pregnancy and breastfeeding Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.  There are no known harmful effects when this medicine is used by pregnant or breastfeeding mothers.    Side effects Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.  Blurred vision after application. Eye burning/stinging.  The side effects listed above may not include all of the side effects reported by the medicine&amp;#039;s manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.   How can this medicine affect other medicines? If you are using more than one type of eye drop you should administer them at least five minutes apart, to prevent the second drop washing away the first. Use eye gels or ointments last. This medicine has not been reported to affect any other medicines.   Other medicines containing the same active ingredients    Liquifilm tears    Last updated 29.03.2010 "^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.netdoctor.co.uk/medicines/eyes/a7544/sno-tears-polyvinyl-alcohol/>