Energy-saving lightbulbs are causing problems for epileptics, who complain that they cause symptoms resembling the early stages of a fit.
MPs have been receiving worried letters and emails from epileptic constituents who say they suffer light-headedness and discomfort when they turn on the lights.
Epilepsy Action, a support charity, said epileptics were complaining that the lights bring on the same symptoms as those they experience before a seizure.
The Energy Saving Trust said yesterday that it did not believe the energy-saving lightbulbs were to blame for the effects. "We have no evidence that they cause a problem," said Philip Selwood, chief executive. "There have been issues in the past about the frequency of some of these bulbs but that has been resolved."
Experts are at a loss as to why the bulbs are affecting epileptics in this way because most do not flicker at an "epileptogenic frequency". They say research is urgently needed to discover the reason for the reported side-effects.
Geoffrey Cox, MP for Torridge and West Devon, who has been contacted by constituents concerned about the impact of the fluorescent bulbs, said research was needed to find out how many people with epilepsy were affected.
"Epileptics in my constituency are concerned that the energy-saving lightbulbs are affecting them adversely. I was sufficiently concerned about this to ask a question in Parliament," he said.
Ivan Lewis, the Health minister, said that "some people living with lupus and epilepsy and other long-term conditions may be affected by energy-saving lightbulbs, but no assessment has been made of the number of people affected."
There are many different types of energy-saving lightbulbs, and experts are unclear if the colour of the light or the flicker of the bulb has an effect.
"Compact fluorescent lamps take a long time to come to full brightness. Whether the uneven spectral power distribution is the reason for people's aversion to these lamps, I don't know, but aversion is certainly quite prevalent," said Dr Arnold Wilkins, a research psychologist at the University of Essex, who specialises in lights and photosensitivity.
Epilepsy Action said it was only just beginning to hear about the problem.
"There is not much doubt that people with epilepsy are concerned that it can cause seizures. People who know about epilepsy feel they are going to have a seizure. We don't really know why, and have just picked up on this. It is something that has just cropped up recently and we are trying to get to the bottom of it," said an Epilepsy Action spokesman.Reuse content