Dry Eyes

• One of the most common reasons for blurry vision while wearing contacts is that your eyes are dry. Some people have a medical condition that causes dry eyes, called dry eye syndrome, but others' eyes are irritated by the contacts themselves. To remedy the situation, carry saline eye drops with you at all times. Be sure the brand you buy is safe to use with contact lenses. Apply drops throughout the day as necessary, being sure not to use them more often than the product recommends.
  
  

Scratched Contact Lens

• A defect on the lens can cause blurriness. If it's a new contact lens, it's possible that it was a manufacturer's defect. If you've been wearing the contact a while, you could have easily scratched it with your nails while cleaning it, putting it in your eye or removing it.
  
  You'll usually notice that only one eye is blurry. Remove the contact from this eye and examine it in the light. If you see a visible defect, throw the pair away and start with a new set, assuming you're using disposable contacts.
  
  

Torn Contact Lens

• Like scratches, tears frequently occur with contact lenses. They can be very small and barely detectable to the eye, but when you're wearing the contacts a tear can cause great irritation. If you have a tear in your contacts, you should throw out the pair and start with a new one.
  
  A torn contact can be dangerous if a small piece of the contact separates and becomes lodged in your eye. It can be difficult to remove and lead to infections.
  
  

Wrong Contact Prescription

• If you haven't had your eyes examined in a couple of years, it's highly likely that your prescription is outdated, thus making your contacts blurry. Schedule an eye exam to confirm your prescription is up to date. Vision can worsen with age, and those with astigmatisms can experience shifts from year to year and force changes in the prescription.
  
  

Dirty Contacts

• Although it may seem obvious, you must keep your contacts clean to avoid blurry vision. You can get dirt, oil or leave fingerprints on the surface of your contacts when you place them in your eyes. Women who wear eye makeup can unknowingly get flakes of mascara or eyeshadow in their eyes, and thus on their contacts.
  
  It's imperative that you clean your contacts before you apply them, every time. Some lens solutions are "no rub" and you simply need to squirt the solution on them. Other solutions require you to submerge the contact in the palm of your hand and swish it around to remove impurities.