There are various causes for allergy related to contact lens users:

• Allergy to contact lenses solution
• Allergy to deposit protein
• Allergy to the contact lenses itself.

In this article we will focus on the most common cause ; contact lenses cleaning solution. We will discuss deposit and contact lenses in other articles.

1)   What are contact lens solutions?

We can split contact lens solution in two categories; all-in-one solution and peroxide solution.

Less and less popular amongst contact lenses wearers is peroxide solution; based on water, mixed with hydrogenated disinfecting agents and other substances. Peroxide solution is very powerful against germs. The lenses must be immersed in the solution for several hours to be decontaminated and the cleaning process is complex. The main problem of peroxide solutions is although it is effective, it is also very strong! After immersion of lenses in the oxidizer, it is mandatory to rinse to neutralize the patented product residue. Too many undisciplined lens wearers have had bitter experiences in this area causing stinging and burning. This problem has resulted in increased popularity of the multifunctional solutions.

The all-in-one solution offers everything in one bottle where decontaminant agents are used to clean the contact lenses. When you put the lenses in their box with solution for the night, it is this agent who will remove all the germs.  Surfact agent has some lubricating and moisturizing properties. It is easier and more comfortable to put your lenses on the eye thanks to this agent.  The buffering agent allows the contact lenses to be more comfortable during the day, and the chelating agent prevents the formation of protein deposit.

2)   Allergy and the preservative

All these chemical agents are sterile over months or years. That is why laboratories are using preservatives. With them, you can use your all-in-one solution for a longer time period, and sometimes it helps the decontamination agent to be even more effective. But unfortunately, they are also cause of certain allergy.

The most common preservative are PHMB (polyhexamethylene biguanide) and the Polyquad. They are both very effective, but their composition itself is too strong for certain people.

It can be difficult to recognize an allergic reaction in other symptoms. Allergy can take different forms; eye dryness, conjunctivitis, inflammation, tears production constantly.  There are some simple recommendations to avoid these problems.

3)   Advise to avoid allergy

To avoid contact lens solution related allergy:

•   Use a peroxide solution like Oxysept  1 step.  This type of solution is free from preservatives, so you avoid the risk of allergy. Remember to neutralize the solution before putting the contact lenses on your eye. Peroxide is a toxic product before neutralized properly.
•   Use an all-in-one solution, but be sure to complement by rubbing your contact lenses every morning with saline during 30 seconds to remove as much preservative as possible from the contact lenses.
•   If you still have an allergic reaction despite precautions mentioned above, use daily contact lenses. You are sure to have new and sterile lenses every day.

And do not forget that there are some important rules to follow in order to prevent contact lens allergy in general:

• Washing hands with soap (preferably 15 seconds to get rid of all the germs) and dry them with a clean towel  is very important before you handle lenses.
• Clean the case meant for storing lenses regularly with saline solution.
•  Wear glasses intermittently to reduce the symptoms and discomfort with contact lenses. You need to wear your spectacles at least 1 day a week. Your eye is like any other organ, sometimes, it needs to rest.