The watchdog has issued advice to retailers not to stock Rampant TTs, marketed by Manchester-based 247 Enterprises.
Stores that refuse to comply could get a black mark against their name in future licensing applications.
Portman’s independent complaints panel ruled that Rampant Tts’ packaging didn’t make its alcoholic nature clear and encouraged down-in-one consumption.
Its publicity material was judged to promote sexual success and encourage irresponsible consumption.
The product’s website was also found to have breached the code by showing consumers who appeared to be drunk and under 25, including an image of a woman holding up a sign saying: “I’m off my tits”.
247 Enterprises director Dave Fash said: “These pictures were of people who weren’t anything to do with the company and we took them down as soon as Portman first wrote to us.
“It’s a bit of a joke, to be honest. I’m disappointed because there are loads of other products like this on the market. We’ve done as much as we can in line with the Portman Group, but they’ve just got nothing better to do.
“The test-tubes are only about 10% of our sales portfolio, so it’s not going to have a very big effect on us as a company.”
Portman chief executive David Poley said: “This company has shown a profound disregard for the industry’s responsibility standards.
“It’s totally unacceptable to publicise some of the worst aspects of consumer behaviour in alcohol promotions.
“This type of dubious marketing could worsen drinking culture and invites criticism of the industry.”
The complaint was made by the Gin & Vodka Association.