What is photo-kerato-conjunctivitis?

This is a painful eye condition caused by excessive exposure to UV radiation.

It is exactly the same as "snow blindness" in skiers, from excessive UV reflected from snow, and "arc welder's flash" experienced by people working with metal welding equipment, who have not worn protective glasses. It is very painful - like having sand in your eyes - and it is caused by damage to the delicate transparent cells on the surface of the eye (the cornea) and the lining of the eyelids. Fortunately, only the superficial layers of the eye are affected; the lens and retina are not damaged (the UVB does not reach the deep structures of the eye) and so it does not cause permanent blindness.

The pain is protective (it makes sufferers close their eyes) and healing begins at once, when the harmful UV light is removed. Unless there have been serious burns, the eyes heal remarkably quickly. The damaged cells are replaced within days and the pain disappears.

Most cases open their eyes again within 2 - 3 days and all symptoms are gone within a week or so, with no medication being necessary. If there has been skin damage to the eyelids this may take a little longer and veterinary examination is essential in case the damaged skin has become infected. We have heard reports of some cases with a sticky discharge from the eye and/or peeling of the skin around the eyelids.

"Help! I think my reptile has this problem, what shall I do?"

Please don't panic. Please check out the following points:

1. Is your reptile ill? (Inactive, not basking, not feeding?)

If your reptile is ill, the first thing you must do is seek specialist veterinary advice. There are many causes of illness in reptiles which have nothing to do with exposure to UVB light....A sick reptile urgently needs to be examined by a veterinary surgeon experienced with reptiles.

2. Does your reptile refuse to open its eyes, or have swollen eyelids? (Symptoms of photo-kerato-conjunctivitis)

Please understand that there are many other causes of eye problems in reptiles. Turtles and tortoises are particularly susceptible. Similar symptoms can occur with eye infections, certain vitamin deficiencies and even dust or sand in the eyes. Your reptile should be examined by a reptile specialist vet to rule out other causes - which may need specific treatments such as antibiotics. If you are concerned that the lamp may have contributed to the problem, print out some of the information from this page to show your veterinarian.

However, if your reptile is showing these symptoms AND you have recently installed one of the lamps featured in this report - especially if your reptile can get close to the lamp - yes, it is possible that your pet has developed photo-kerato-conjunctivitis.

• It will do no harm, in the short term, to switch off the new UVB lamp for 1 - 2 days. (The sun does not shine every day, even in the tropics.) Do not switch off the (non UVB) basking light or heating! If the UVB lamp was the source of the problem, recovery may be seen (but do not wait 1-2 days before seeking veterinary help, if your reptile is ill.)
• Double check the distance of your lamp from the reptile. Check out the manufacturer's instructions regarding minimum basking distances and also read our reports carefully, to see whether at the distance your lamp was set, the UV radiation could have been excessive. If you plan on continuing to use the lamp, ensure that when you use it again, it is placed at a suitable distance.
• Were you using an aluminium reflector? This can boost the UVB beneath a lamp to extremely high levels. Check the details in our report.
• Was your reptile able to move into a sheltered area away from the UV lamp? It is essential that every set-up provides areas of shade; a UVB gradient is as essential as a heat gradient.
• If your reptile has stopped eating and drinking, there may be a risk from dehydration, particularly with young hatchlings. Seek veterinary advice about offering small drinks of water (usually by dropper; never force fluids into the mouth as there is a risk of getting water into the lungs)
• Once a reptile has completely recovered from photo-kerato-conjunctivitis, UVB lighting should be provided again, this time at more suitable levels. Some owners may wish to re-introduce the lamp which caused the problems, but at a more appropriate distance. Others may wish to replace the lamp with one which does not contain the "phototherapy" phosphor described in our reports.

It might seem appropriate to re-introduce UVB gradually. We suggest that initially, the appropriate level of UVB could be offered for a shorter period of time than normal, building up to the "full day" over a period of a week or so. Obviously, we would recommend that you observe your reptile very carefully for any further problems.

"How should I respond to this report?"

(Revised - September 2009)

1. When reports of photo-kerato-conjunctivitis first started appearing, back in 2007, very few people knew what the problem was, and we encouraged reptile keepers to pass on the information to their veterinarians, their reptile clubs and groups, and internet forums.
The condition is still not widely recognised. Because the most well-known companies selling the "problem" lamps responded promptly (either withdrawing lamps from sale or increasing recommended basking distances and pre-burning the lamps in the factory, to reduce their output) the number of reported cases fell rapidly throughout 2008, and we're glad to say, cases are now rare.
Manufacturers worldwide are becoming aware of the problem with "non-terrestrial", abnormally short-wavelength UVB and responsible companies are ensuring that their lamps do not emit such radiation. This is excellent news, but it is still important that reptile keepers and their veterinarians are aware of the symptoms and remain watchful - particularly when new products are being introduced to a collection. Please don't hesitate to share what you've learned about this subject.

2. If your own reptiles have developed photo-kerato-conjunctivitis, and you have reason to believe that this was due to your use of any UV lamp currently sold for reptiles, you may wish to write a case history. If so, we suggest that you send one copy to us, and one to the contact address for the company who manufactured your lamp. (This can usually be found on the company's website.) Please include your name and address in your report, although we will keep this completely confidential. We also suggest you inform your veterinary surgeon, and the store where you purchased the lamp. We believe that this is important, as it will help prevent further cases. Many veterinary surgeons will not have seen a reptile with photo-kerato-conjunctivitis before, and will be interested to hear of the report. Pet stores may also be glad to know about it.

3. You are welcome to give a link to us - http://www.uvguide.co.uk - but please do NOT copy and paste anything from this report. This could easily be misleading, taken out of context. It's also unfair on the people who have kindly offered their distressing pictures of much-loved pets. These belong only in this report.

We have not tested every lamp of every brand in the world - nor can we hope to, nor should we have to! We are not in the pet reptile lighting industry! We hope our findings are helpful, however. We are endeavouring to test new lamps from major companies but we still have a number of new products awaiting testing. If you buy a new lamp, read all the accompanying data carefully. Always follow the manufacturers' instructions and double check your distances, temperatures at the basking spot, and provision of shade. And above all... observe your reptile and his response to the lamp.