A new study from the University of Valencia (UV) has indicated that exposure to ecstasy or cocaine during adolescence enhances the risk of addiction.
"Although MDMA and cocaine are psychoactive substances frequently used by teenagers, very few studies have been done to analyze the short and long-term consequences of joint exposure to these drugs," said Jose Minarro, lead author of the study and coordinator of the Psychobiology of Drug Addiction group at the UV.
The study has shown for the first time that exposure to these drugs during adolescence leads to long-lasting changes that increase the reinforcing power of ecstasy or MDMA, and which last until adulthood.
To reach the conclusion, the researchers studied the joint consumption of different drugs in order to carry out an in-depth examination into the effects of this interaction.
They administered MDMA, cocaine and saline solution to mice over an eight-day period.
"The animals exhibited an increase in vulnerability to re-establishing behaviour (relapse), showing a preference for certain environments previously associated with the pleasant effects of the drug", said Minarro.
The results highlight that the so-called 'reinforcing effects' are greater in adult mice treated with ecstasy or cocaine during adolescence than in adolescent mice not exposed to these drugs.
"Adolescence is a critical stage in development, during which time drug consumption affects plastic cerebral processes in ways that cause changes that persist right through to adulthood", Minarro added.
The study has been published in the journal Addiction Biology.