The rising sale of luxury toilet paper is taking its toll on British pipes, according to a study.
The average cost of unblocking a loo is £90, British Gas said.
Research conducted for British Gas found the products were partly to blame for a 10% rise in bathroom blockages it has dealt with this year.
Its report said low-priced and recycled paper broke down in minutes, while luxury brands took up to half-an-hour.
Moisture wipes, designed for use by children, had failed to break down after five days, British Gas said.
The plumbing arm of British Gas unblocked more than 35,000 toilets in the first six months of 2004, the company said.
Sainsbury's low price - 3 mins
Andrex Regular - 6 mins
Andrex Aloe Vera - 26 mins
Izal medicated - 30 mins
Newspaper - 60 mins
Andrex Moist wipes - 5 days
Other wipes - 5 days
SOURCE: British Gas survey
It added that the average cost of calling out a plumber to fix the problem was £90 each time.
British Gas commissioned an independent test to compare how long various brands took to break down in water, suspecting the luxury products now available to consumers were partly to blame.
It found a "low price" tissue from a supermarket took three minutes to disintegrate, while a brand of recycled paper from the same chain took four minutes.
The thicker tissues took up to 30 minutes break down, while two brands of moist wipes still had not disintegrated by the time the experiment ended five days later.
Alan McLaughlin, a spokesman for British Gas, said even newspaper broke down quicker than the moist wipes.
"We had newspapers included in the experiment mainly to amuse ourselves really because it harked back to the days of the outside privy," he said.
"To see some products lasted longer than newspaper was slightly shocking. It's clearly not kind to your behind."
The rising popularity of the products was putting the UK's toilets under "considerable strain", but it was "very reassuring" to see recycled and budget toilet rolls performed best in the study, he said.
Despite the results, he acknowledged that the choice of product a customer made would essentially come down to personal preference.
"Some are better for comfort while others appear to be better for your pipes - and your pocket," he said.
A spokeswoman for Andrex, whose products were tested in the study, said: "It would be impossible for us to comment specifically on this test because we have not been made aware of the conditions under which it was conducted."
"In our experience the biggest cause of blocked drains is due to the condition of the drainage system itself," she said.