Consumer demand has led manufacturers to develop new soft contact lenses that enable long periods of uninterrupted wear with minimal lens handling and cleaning. In order to satisfy the health requirements of the eye, revolutionary materials have been developed that overcome many of the problems associated with the previous generation of soft contact lenses when used for overnight wear.

The new lenses are made from materials known as silicone hydrogels that allow around six times more oxygen to reach the eye compared to ordinary soft lenses. There are currently two such lenses available in the UK: Focus Night & Day and PureVision. They are available to correct short-sightedness (myopia) and long-sightedness (hyperopia) and they have been trialled by patients in studies carried out in many countries.

Silicone hydrogel lenses may be prescribed for daily wear, or for overnight use for up to 30 nights of continuous wear. Your contact lens practitioner may suggest daily wear or a shorter wearing time depending on your individual needs. Not everyone may be suitable for 30-day continuous wear.

Wearing contact lenses on a continuous basis can be very convenient but the risk of serious complications (such as eye infections) with silicone hydrogel lenses, although thought to be very low, is yet to be determined. You should carefully discuss the benefits and risks of this option with your contact lens practitioner before proceeding.

The success of any new contact lens is also dependent on appropriate use by the wearer and it is therefore very important to adhere to the wearing times recommended by your practitioner. All contact lens wearers should pay attention to the comfort of their lenses, the appearance of their eyes and the quality of their vision. If you experience any problems such as redness, pain or blurred vision, you should remove your lenses straight away and consult your contact lens practitioner at once.

If you use continuous wear lenses you should have an up-to-date pair of spectacles for when you need to remove the lenses, such as if the eyes are irritated or during periods of ill health. It is now recognised that swimming while wearing contact lenses, showering and hot-tub use can be associated with complications and should generally be avoided.