Stress and substance abuse are bosom buddies. From anecdotal evidence of over-worked recovering addicts spiraling back into addiction to neurological research, the relationship between stress and drug abuse has long been established. Historically, these findings have led to stress management courses and other interventions aimed at helping addicts more successfully manage their stress, but as more research emerges, medical treatments to prevent stress-induced relapse are looking more likely. Researchers from Brown University recently identified the process by which stress causes relapse, which has opened the door to a new potential treatment option. Stress and Drug Addiction \u2013 The Psychology The psychology behind stress-related drug-seeking behavior is much more clearly understood than the neurology. Most drugs of abuse cause some sort of euphoria or profound relaxation in the user, and this direct effect of drugs often makes them superficially effective for stress relief. The individual might go for a drink with some colleagues after work, for example, and use it as an opportunity to unwind after a long day. Similarly, he might go out to a club over the weekend and take ecstasy as a \u201creward\u201d for his week of work. The more this association between stress relief and substances builds up in the mind of the user, the more they become psychologically dependent on the drug. You don\u2019t need to take many mental leaps to understand the psychological link between stress and drug addiction. Drugs are seen as a solution to the problem of stress, but the fact that stress is inevitable means that addiction is extremely likely for anybody using a substance for the purpose of stress relief. Even if the individual stops taking drugs for an extended period of time, a particularly notable source of stress could be enough to drive them back to old habits. Stress and Drug Addiction \u2013 The Neurology To understand the impact of drug addiction, you need to understand how the body and brain ordinarily deal with stress. In response to a stressor, the brain releases two groups of chemicals, hormones and neurotransmitters (chemical \u201cmessengers\u201d for the body and the brain, respectively). Your brain first releases a chemical named corticotrophin-releasing factor (CRF), which then triggers the release of adrenocorticotropin (ACTH). This then stimulates the adrenal glands and leads to the production of cortisol, which counteracts the stress the body is experiencing. The presence of cortisol in the blood tells the brain that CRF and ACTH are no longer required, unless the stressor is a particularly serious one. To see if the stress-response system operates differently in individuals addicted to drugs, Dr. Mary Kreek of Rockefeller University and her group of researchers used a drug that blocks the production of cortisol. In people not suffering from drug addiction, the absence of this chemical means that nothing stops the brain from producing CRF or ACTH and as a result, measured ACTH levels increase. However, for current heroin users, the drug had little effect on ACTH levels at all, leading to only a modest increase. If the drug is given during withdrawal from opiates, the level of ACTH increases to twice as much as in non-addicts, showing a much greater sensitivity to stress. It takes around three months of methadone maintenance to bring the body\u2019s stress-response system back to normal. This means that the brain of an addict will respond much more sensitively to stress, making relapse much more likely in these situations. The New Research The psychological explanation for the link between stress and drug relapse offers a useful way to understand the issue, but biological models of how this happens open up the possibility of creating drugs to prevent it. This is the aim of Brown University\u2019s research, which identifies several key pathways in the process of stress leading to a relapse. The researchers found that the kappa opioid receptors in the ventral tegmental area of the brain are activated by stress, which is implicated in the process of stress-induced relapse. This means that an antagonist drug which works on these receptors could short-circuit the stress response and therefore reduce the likelihood of relapse. The experiment to test the effectiveness of this medication has been conducted in rats, and the initial results are positive. The study took once cocaine-addicted rats and placed them under stress to see if they attempted to use cocaine again. Those who received the antagonist didn\u2019t relapse, but the ones who didn\u2019t take the drug took cocaine under stress. Implications for Addiction Treatment If the drug is tested further and has positive outcomes in human trials, it could prevent stress-related relapse altogether. As one of the most common reasons for relapse, this could be an invaluable tool for rehab centers all across the country. It\u2019s important to note that it wouldn\u2019t be a \u201ccure\u201d in any sense of the word, but it would help users stay abstinent long enough for psychological treatment to have an effect. For that reason, this could become a landmark piece of research in substance abuse treatment.