Last year there were 581 deaths, the second highest number recorded. Official statistics showed the 2012 total was up 199, or 52%, on the figure for 2002.
More than one-third of those who died last year were over the age of 35, and three-quarters were men.
David Liddell, director of Scottish Drugs Forum, said the figures highlight the need for a greater distribution of naloxone - an emergency antidote for opiate overdoses.
He said: "The continued high level of deaths highlights the need to reduce fatalities especially among heroin users, who remain - by far - the group most likely to die from drug use in Scotland.
"The high level of deaths among older opiate users - 63% of all deaths are among people aged 35 and over - remain a significant concern and re-emphasise the need for services to be more targeted towards the needs of this group of people, who are likely to have a range of complex needs.
"The Scottish Government's programme to distribute naloxone is one of the measures to help cut the drug deaths toll, but more needs to be done to ensure greater distribution and take-up.
"Our view is at least 40% of the estimated 59,600 people with very serious drugs problems need to be provided with naloxone to make a substantial impact on the deaths."
The statistics were published by the General Register Office for Scotland. Among the report's main findings was the conclusion that the 581 deaths registered last year was down three, or 0.5%, on 2011's high of 584.
Methadone was implicated in, or potentially contributed to, 41% of last year's drugs-related deaths.
Deaths where so called "legal highs" were implicated have also been recorded. Last year, there were 47 deaths where they were involved. In five of those cases, they were the only drug present.
There were 199 drug-related deaths of people aged 35-44, 34% of last year's overall total. In the 25-34 age bracket, there were 171 drug-related deaths, or 29%.
Men accounted for almost three in four drug-related deaths, or 72%. Of the total number of deaths last year, heroin and/or morphine potentially contributed to 221 fatalities. Methadone was implicated in or may have contributed to 237 deaths. While this was down by 38 on the 2011 figure, it still represented a "large increase" compared with 2008 to 2010, statisticians said. In 68 deaths, methadone was the only drug implicated, alongside alcohol in some cases.
Community Safety Minister Roseanna Cunningham said: "The Scottish Government is dealing with a legacy of drug misuse that stretches back decades. As in previous years, the statistics today show many of these deaths are older drug users who have become increasingly unwell throughout the years.
"It is encouraging fewer young people are dying. This is in keeping with wider statistics on drug use that show a decrease amongst the general population, and that use by young people is at its lowest for a decade.
"There has also been a substantial drop in the number of deaths where methadone alone is implicated, a fall of 39% from 112 in 2011 to 68 in 2012."
Dr Roy Robertson, of the National Forum on Drug-related Deaths, said: "It is always disappointing to see the depressing loss of life from drug-related causes."