This may be completely surprising, but more than half of all schizophrenics depend on narcotics, nicotine or alcohol. In an attempt to figure out a reason behind this astonishing link, researchers found that this addiction can be the result of the very treatments these patients are subjected to. It was suggested that the continuous, but not intermittent, delivery of antipsychotic drugs along with an injection of amphetamine leads to an uncontrollable craving for the sensation brought upon by drug consumption.
Experts believe that antipsychotic drugs block some dopamine receptors within the central nervous system. Its long term use can supposedly provoke a hypersensitivity to dopamine, which translates into a strong reaction to drugs, including amphetamines. During the research, three experiments were initiated on three groups of rats, namely a control group, a group receiving haloperidol continuously, and a group receiving haloperidol intermittently. It was mentioned that haloperidol may be a common antipsychotic drug.
“The secondary effects of antipsychotic drugs are numerous and invasive: facial tics, apathy, depression, weight gain, etc. Schizophrenics suffer, even when treated and many believe they consume other stimulants to appease the secondary effects. But, in fact, it only makes the situation worse. The risk of hospitalization increases and the potential success of the treatment decreases,” explained Anne-Marie Bédard, a Université de Montréal master’s student of pharmacology and lead investigator of the research.
In the first experiment, researchers examined the pursuit of a conditioned reward. The subject animals were used to seeing a light and hearing a sound whenever a reward was delivered, in this case a few drops of water. When this Pavlovian association was learned, the water was but the light and sound could still be activated with a pedal. Also a second pedal playing a similar role was employed, but it was inoperative. Then the rats explored the role of both these pedals before receiving a dose of amphetamine. The group which received continuous doses of haloperidol purportedly pushed on the active pedal more than 150 times to obtain the light and sound.
The group receiving haloperidol intermittently, on the other hand, may have pushed on the pedal around fifty times. During the second experiment, two genes were employed to measure the cellular activity of this extreme behavior. And finally in the third experiment, the rats were placed in a plexiglass cage and their movements were recorded through motion captors. Those provided with continuous doses of haloperidol appeared much more agitated than the two other groups. In conclusion, it was asserted that the chronic consumption of antipsychotic drugs in schizophrenic individuals who consume drugs can intensify their addiction.
The research is published in Neuropsychopharmacology.