The watchdog has issued advice to retailers not to stock Rampant TT, 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 TT 's 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
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
with 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.
"The test-tubes are
about 10% of our sales portfolio, so it's not going to have a very big effect on us as a company."