A licensing regime for premium rate TV phone service providers is to be set up following complaints that viewers have been ripped-off.
Brainteaser, hosted by Alex Lovell, is normally shown on weekdays
Regulator Icstis met broadcasters to discuss allegations some shows did not give callers a chance of winning.
It has asked programme makers to carry out a thorough review of all current and forthcoming premium rate services.
Earlier broadcaster Five suspended quiz shows using premium rate services after an audit showed winners had been faked.
Concern centred on Five's show Brainteaser, produced by Cheetah Television, a subsidiary of Big Brother creators Endemol.
Viewers were asked to solve a word puzzle within five minutes but when the audience failed to get the right answer, fictional names of winners were listed on screen.
On one occasion a member of the production crew went on air posing as a "winning contestant".
The problem came to light when Five began a review of its premium rate telephone services.
TV watchdog Ofcom is to investigate, while Five's chief executive Jane Lighting apologised to viewers, saying she was "shocked and disappointed" that their standards had not been maintained.
Endemol issued a statement apologising, backing the suspension and saying it would work to rectify the situation.
Five is working out how many callers were affected on the five occasions winners were faked, and will be giving them a full refund of the cost of the call, said the channel.
Following Thursday's meeting with broadcasters, producers and telephone service operators, Icstis chairman Sir Alistair Graham said a full review of services should be carried out as an "absolute priority".
He said the licensing regime could be introduced within three months.
"There is no doubt that public trust and confidence in these services has been damaged by the allegations that have been made in the last few weeks," said Sir Alistair.
"It is in everyone's interest to ensure that services are reliable and trustworthy as well as entertaining and fun."
Other measures announced were a systematic monitoring of premium phone services and the publication of clear rules on competitions.
Icstis is already investigating six shows: Channel 4's Richard and Judy, the BBC's Saturday Kitchen and ITV programmes the X Factor, Ant and Dec's Saturday Night Takeaway, Soapstar Superstar and I'm A Celebrity.
ITV's Saturday Night Takeaway is one show under scrutiny
Allegations of irregularities include viewers being encouraged to enter competitions after the winners had been chosen.
On Tuesday, ITV suspended all its premium-rate phone-in competitions and votes in a move which saw its quiz channel ITV Play taken off air.
Industry magazine Broadcast said media analysts at Credit Suisse estimated the suspension could be costing the broadcaster £1.5m.
The BBC's Saturday Kitchen is also being examined after viewers were asked to phone in to appear on the following week's programme, despite it being filmed just minutes after the live show.