Record numbers of people are dying from drug poisoning, new figures reveal.
There was also a sharp jump in fatalities involving cocaine last year, while the number of deaths linked to anti-depressants was at its highest level for 15 years.
There were 3,346 drug poisoning deaths registered in England and Wales in 2014, the highest since comparable records began in 1993. Two thirds involved illegal drugs.
The mortality rate from drug misuse was the highest ever recorded, at 39.9 deaths per million population. Statisticians said the increase in mortality rate for all drug-related deaths for both men and women is likely to be related to the availability and consumption of heroin and morphine.
Campaigners described the figures as "tragic", while public health officials said they showed a global increase in availability and purity of heroin was taking effect.
The Office for National Statistics (ONS) figures cover accidents and suicides involving drug poisonings, as well as deaths from drug abuse and dependence.
Drug-related fatalities now appear to be concentrated among the middle aged. For the first time the highest mortality rate from drug misuse is for people aged between 40 and 49. The pattern is in line with figures showing people receiving treatment for drug misuse are getting older.
Deaths involving cocaine increased by almost 50% to 247, with research suggesting an increase in purity has been a factor in the trend.
There were 517 deaths involving anti-depressants in 2014, the highest number since 1999.
Deaths involving heroin and/or morphine increased by almost two-thirds between 2012 and 2014, from 579 to 952, with increases seen across nearly every age group.
The ONS highlighted evidence that suggests an increase in purity and volume of the substance following a "heroin drought" in 2010/11, while also citing falls in the cost of the drug as a possible factor.
There were 67 deaths involving new psychoactive drugs (NPS) - sometimes referred to as "legal highs" - and a record 258 linked to diazepam, which is used to treat anxiety.
Fifty fatalities involved ecstasy, following reports raising concerns about "super strength" versions of the party drug.
The drug misuse mortality rate increased in England but fell in Wales. Regionally, it was highest in the North East, and lowest in London.
Yasmin Batliwala, chair of drug charity WDP, said the figures demonstrate that "we are simply not doing enough to tackle drug misuse in this country", adding: "The lack of a current and targeted national drugs strategy is a blatant demonstration of this failure."
Simon Antrobus, chief executive of substance misuse charity Addaction, said"These tragic figures paint a stark picture of the shifting landscape of drug misuse in England and Wales.
"Drug treatment services across the country have seen an increase in the number of people seeking help for opiates and/or crack cocaine and this is only likely to increase further as the effect of increased opiate availability and purity is felt."
Rosanna O'Connor, of Public Health England, said the rise in deaths caused by heroin use is a "great concern".
She added: "The increased global availability and purity of heroin is clearly having an impact in England. Fewer people are using heroin but the harms are increasingly concentrated among older, more vulnerable users."
The Department of Health said any death related to drugs is a "tragedy", adding: "Our drugs strategy is about helping people get off drugs and stay off them for good, and we will continue to help local authorities give tailored treatment to users."