The last survey, carried out in 2003, said that men were drinking an average of 17.2 units a week, while women consumed 6.5 units.
But a report by Health Scotland this week is expected to suggest people could be drinking twice that amount.
Experts blame the growing popularity of high-strength wines and beers, as well as a tendency for people to drink larger measures, both in bars and at home.
NHS Health Scotland believes previous surveys of alcohol use may not be accurate because of these changes in drinking habits.
The new report out this week – called How Much Are People in Scotland Really Drinking? – comes after The Scotsman this month revealed that alcohol abuse is costing Scotland more than 2.25 billion a year, double the previous estimate.
A Scottish Government spokesman said a new alcohol strategy was being published this summer.
He said: "It is examining all areas, taking a wide-ranging look at possible measures that might tackle Scotland's alcohol problems."