The 6 most frequently asked questions about peroxide solutions for contact lenses
Hydrogen peroxide (H2O2) is a colourless liquid, usually available as an aqueous solution, which is mainly used in the production of cosmetics, for bleaching cotton and even as rocket fuel.
But peroxide can be even more versatile. It is also used in contact lens solutions. Here the agent plays an important role in cleaning and disinfecting contact lenses. Peroxide is very popular with allergy sufferers and lens wearers who suffer from dry eyes.
How does this unique care product work? We have answered the six most frequently asked questions about peroxide solutions.
1. What are peroxide solutions?
Both hydrogen peroxide and multi-purpose solutions clean and disinfect contact lenses by breaking up and removing trapped deposits, proteins and fat deposits (lipids).
However, unlike multi-purpose solutions such as Solunate, peroxide solutions are preservative-free, which makes them suitable for allergy sufferers who react to certain preservatives. These solutions, also called peroxide systems, are particularly well tolerated and extremely effective against germs.
Peroxide solutions are mainly used for disinfecting soft contact lenses, but some of them can also be used for the care of hard contact lenses.
2. How are peroxide solutions used correctly?
The use of peroxide systems requires extra care, compared to multi-purpose solutions. After cleaning the contact lenses, the hydrogen peroxide contained in the solution must be neutralised, before the lenses can be worn.
If neutralisation is not carried out properly, the hydrogen peroxide that gets into your eyes can cause stinging, burning and temporary damage to the cornea. The neutraliser converts the peroxide into water and oxygen, ensuring that you can use your lenses without problems.
3. What are single-stage peroxide systems?
With a single-stage peroxide solution, the lenses usually have to be kept for several hours in the peroxide system until the solution is completely neutralised in the special container provided.
Single-stage peroxide systems are filled into a special contact lens container, then they are neutralised with a special tablet, which is usually supplied by the manufacturer together with the solution.
4. What about two-stage peroxide systems?
Two-stage peroxide systems disinfect your contact lenses thoroughly, as the concentration of hydrogen peroxide remains constant throughout the disinfection process.
In a two-stage peroxide system, the peroxide solution is disposed of at the end of the disinfection period and the container is filled with a second solution – the neutralisation solution. To avoid an unpleasant burning sensation, it is important to leave your contact lenses in the neutralisation solution for as long as the manufacturer prescribes.
If the solution is not completely neutralised, it could still be harmful to the eyes. In this case, you can soak the lenses in a normal saline solution before inserting them.
5. How long does the neutralisation of peroxide systems take?
The neutralisation process usually takes up to six hours. However, please observe the neutralisation time specified by the manufacturer in the package leaflet. After neutralisation, your contact lenses must not come into contact with the peroxide solution.
The duration of the neutralisation process in two-stage systems is somewhat
shorter than in one-stage systems, because in the two-stage system only the
peroxide remaining in the contact lenses needs to be neutralised and not the
entire contents of the container.
6. What is the safest use of peroxide solutions?
- Before using a new contact lens solution, read and carefully follow all instructions on the package and bottle.
- Be sure to use the special contact lens case that comes with your hydrogen peroxide contact lens solution. Do not use an old lens case when you receive a new bottle of peroxide-based contact lens solution. If you do, the peroxide will not be neutralised correctly.
- Leave your lenses in the solution for at least 6 hours to allow the neutralisation process to complete.
- Never rinse your lenses with hydrogen peroxide solutions and never put hydrogen peroxide solution directly in the eyes, so as to avoid any form of damage.
- Do not allow anyone else to use your hydrogen peroxide solution. Your friends and family members may mistake the peroxide solution for a multi-purpose one and not use it according to the specific instructions for hydrogen peroxide solution.