Skull Splitter is named after the seventh Viking earl of Orkney
A House of Commons motion has been tabled aimed at protecting a Scottish ale called Skull Splitter.
The Orkney Brewery fears the product could be withdrawn from sale following a report commissioned by alcohol watchdog the Portman Group.
It has been claimed its Viking-branded bottles have an aggressive theme.
Orkney and Shetland MP Alistair Carmichael said losing the name would be a serious setback, and called for the complaint to be rejected.
Skull Splitter, an 8.5% ale created more than 20 years ago, is sold internationally.
The brewery said the ale was in fact named after Thorfinn Hausakluif, the seventh Viking earl of Orkney, nicknamed "Skull Splitter".
Mr Carmichael said the name would be inappropriate if it were a low-priced drink aimed at youngsters.
But he said it was an award-winning beer which is bought by "discerning drinkers who appreciate its quality and who drink it responsibly".
Orkney Brewery's parent company, Sinclair Breweries Ltd, earlier said it was "stunned" by the complaint and hoped for "common sense".
The Portman Group confirmed a complaint was being investigated.