The ad, by Rainey Kelly Campbell Roalfe/Y&R, promotes Virgin Mobile's 3p text messaging tariff, and depicts bored patients using their thumbs to wreak havoc on nurses and fellow patients.
An ITC spokeswoman said the complainants found the execution offensive because it mocked mental illness and hospital workers.
The ITC is also considering 31 complaints about an Irn-Bru spot by The Leith Agency, in which a baby is tempted out of the womb by a can of Irn-Bru, and 80 complaints about a Lil-lets ad by Us, where a young female TV presenter discusses their ease of insertion and removal with her sidekick, an older man.
In this week's rulings on programmes, the ITC fined TV shopping channel Shop America £60,000 for seven breaches of the code since its launch in 2000, all relating to misleading ads.
Channel 4 was also censured for the drama show 'As If', in which one of the characters took a job as a pizza delivery person for Pizza Hut, and appeared throughout the programme in a uniform, on a moped and carrying pizza boxes heavily branded with Pizza Hut logos.
But the ITC rejected 50 complaints that the animals and insects used in 'I'm a Celebrity Get Me Out of Here' were treated cruelly.
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