The number of drug-related deaths in the UK rose by almost 12% to 2,182 last year, figures showed today.
Heroin and morphine were involved in more than half (52.9%) of the deaths, up from 45.3% in 2008, and more than four in five were accidental overdoses, the National Programme on Substance Abuse Deaths report showed.
The increase in the number of deaths, up from 1,952 in 2008, showed the UK still has a "major problem", the researchers said.
The figures, based on information reported by coroners, showed the number of deaths in England last year was 1,524, up from 1,374 in 2008, while figures for Scotland remained broadly the same - up to 479 from 477.
The number of deaths in Wales (102), Northern Ireland (65) and the islands (12) all rose, up from 62, 30 and nine respectively.
Professor Hamid Ghodse, director of the International Centre for Drug Policy (ICDP) at St George's Hospital, London, which released the report, said the continuing rise was "very concerning and shows that we must not waver in our efforts to prevent the loss of life".
"The effectiveness of both drug abuse prevention and treatment is reflected in the mortality data, so we know we still have a major problem," he said.
"An immediate impact in reducing drug-related deaths could be achieved by improving the availability of effective treatment and rehabilitation services.
"However, in the long run, finding primary prevention strategies that work may be crucial if we want to have a major effect on drug-related mortality."
In the UK, more than three-quarters of the deaths were of men (1,698) and almost two-thirds were of people aged 25-44 (1,415).
But the proportion of deaths from cocaine, amphetamines and ecstasy were all down, with the report authors describing this as a "result of the increasing use of 'legal highs"'.
The Brighton and Hove coroner reported the highest proportion of drug-related deaths in the UK, with 23.55 for every 100,000 people aged 16 and over, while East Lancashire was second with a rate of 14 per 100,000, and North Tyneside third with 13 per 100,000.
Increased seizures of legal highs derived from methcathinone, commonly known as bubbles and meow-meow, were also reported last year, the report's authors said.
Mephedrone was detected in a total of 38 deaths and was the sole direct cause of death in at least two of these, the report found.
In one case, mephedrone and methadone were jointly the cause of death, and in a further two cases, mephedrone was implicated but there were also underlying health issues.
The drug impacted with other substances on the individual's mental health and led to hanging in a further two cases and was a contributory factor in another two deaths by natural causes, the report showed.
The 29 remaining cases were awaiting the completion of inquiries by the coroner or procurator fiscal.
Other figures released today, by the Office of National Statistics (ONS), showed the total number of deaths from drug poisoning fell from 2,928 in 2008 to 2,878 last year.
The highest number of drug misuse deaths occurred in the 30-39 age group for both sexes, the ONS figures showed.
A total of 880 deaths involved heroin or morphine last year, down 2% from 2008, while the number of drug poisoning deaths involving methadone rose by 8% to 408 over the same period.
Cocaine-related deaths also fell between 2008 and 2009.
Whereas the ONS figures cover all deaths registered in England and Wales, the National Programme on Substance Abuse Deaths (NPSAD) report covers inquests on the relevant deaths in a calendar year for which an inquest has been completed by the following June.
The NPSAD report also covers psychoactive drugs, such as prescribed and over-the-counter medicines, as well as deaths resulting from drug abuse and overdoses involving illicit drugs.Reuse content