I am experiencing stiff eyes and blurry vision when I wear contacts
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Blurry visions are mainly caused by dry eyes. Be aware not to use too much saline water drops to resolve the issue, since saline water drops kept at daily usage can be replete with bacteria. 
The long usage of contacts may deplete oxygen proportion of the eye and cause blurry vision. The blur will be gone after 2~3 hours after you take out the contacts. When such symptoms arise, please reduce the usage time of your contacts. 
Also, it is better to refrain from using personal computer or reading a book while wearing contacts because these activities cause the eyes to dry quickly. For the same reason, wearing contacts may cause discomfort in dry indoors. 
Please blink continuously to relieve your dry eyes when you wear contacts. Dry, heated indoors during winter is a perfect place to restrain your dry eyes covered in contacts. During wear, the contacts hinder tears to permeate between your eyes and the contacts and prevent them from lubricating and humidifying your eyes, causing several minor problems. 
The blurry lenses with direct contact to the retina may cause discomfort and congested eyes, and the functionality of the retina can be temporarily decreased due to lack of oxygen supply from the tears. Therefore, uncomfortable wearing experience is a natural consequence of dry eyes. We advise you to wear contacts outdoors and cut back the time of your wear when such symptoms arise. Normally beauty contact lenses are mostly manufactured for short-sighted vision, and therefore the symptoms of blurry vision and discomfort can be greater for people with severe astigmatism. 

Blurry vision can also be caused by remaining protein or fat particles on the surface of the lens. Taking off the contacts and leaving them without thoroughly cleansing will definitely shorten their durability and also decrease oxygen transparency rate. Most contacts remain at par condition for 10 months if they have been treated with care. We cannot guarantee how long the contacts will last if managed at poor conditions.

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