In traditional rehab, 30 days was once the standard. Unfortunately, this had little to do with medical science; it was an arbitrary limit placed by insurance companies on how long they would pay for treatment. And, because the human mind naturally favors quick solutions that involve a minimum amount of pain, the number stuck.

Studies conducted by the (National Institute on Drug Abuse) are offering hard evidence that, when it comes to rehabilitation for drug abuse, the longer the stay, the lower the chances of relapse afterward. In 1999, for example, Bennet Fletcher, one of the organization’s senior research psychologists, published a study in the Archives of General Psychology which showed that cocaine abusers who spent less than 90 days in rehab had a relapse rate of 35%. For those who stayed 90 days or longer, the rate dropped down to roughly half that, at 17%. 

While 90 days is no more a magic number than 30 days, the evidence is conclusive that the odds of relapse are inversely correlated to the amount of time spent in rehab; see a list of statistics backing that up on this page. The reasons why are both biological and psychological.

The Biological Reasons Why a Longer Stay in Rehab is Better

When someone is a long-term abuser of drugs or alcohol, it has a physiological impact. When drug use is discontinued, the damage begins to reverse. This is a process that takes time, for both the brain and the body.

Neuroplasticity and Long-Term Rehab

Neuroplasticity is a scientific term that refers to the brain’s ability to change, which allows it to adapt to its environment. For every habit of thought or action that we have, there is an associated network of connected neurons throughout the brain that “codes” for that habit.

Every time the habit is repeated, the synapses, or gaps in between the neurons, release the neurotransmitter dopamine. Dopamine causes these gaps to grow narrower, strengthening the neural circuit and making the habit easier to repeat the next time around. If the habit ceases to be repeated, the lack of dopamine release causes the synapses to widen again, causing the circuit to atrophy, or weaken.

This explains why the development of a skill—a set of related habits in service of a goal—requires regular practice, and why falling “out of practice” leads to a decline in skill. And, because dopamine is connected to pleasure, it also explains why habits that are inherently pleasurable develop quicker and are harder to break than those that are not.

The process by which someone becomes addicted is a process of neuroplasticity that has been hijacked, producing maladaptive changes in the physical structure of the brain. The things that we get addicted to are things that cause dopamine releases at a level beyond that which the brain has been designed by evolution to handle. That means that the neural circuits that wire for addiction cravings and habits of acting out become unnaturally strong.

When such a person enters rehab, he or she enters an environment in which abstinence is being enforced from the outside. The process of neuroplasticity then begins to reverse itself: starved of dopamine, synapses begin to widen again; the neural circuits that wire for addiction grow weaker. But, because the addiction circuits are unnaturally strong to begin with, they can have a very slow rate of atrophy.

It comes down to simple math: the longer the period of forced abstinence, the weaker the addiction circuits will be, reducing the likelihood of relapse by that much more.

Rehabilitation and the Detoxification Process

When someone is abruptly forced to stop using a substance which they are dependent on, the first thing that happens is that the body begins to flush that chemical out of its system. If the body has built up a high tolerance for the drug, and consequently is used to having a large amount of it, then this can be quite a shock.

The amount of time that the process of detoxification takes varies dependent on the nature of the specific drug that the patient has been using, and can last anywhere from two to four weeks. During that time, the patient usually experiences both physical and mental withdrawal symptoms that range from the merely uncomfortable to the potentially fatal.

Medical treatment is usually required to manage these symptoms. This may involve anything from prescribing medications to help lessen the burden of unpleasant symptoms to constant care to make sure that the patient remains stable. Because of this, most experts agree that detox should always be managed by a professional.

Though forced abstinence is a vital ingredient of any rehab program, it isn’t enough in of itself. As we will see below, the other half of recovery consists of figuring out why the patient uses drugs and then learning new life skills to better cope with these problems. During the detox stage, however, the patient may be simply too sick to do much of this crucial work.

Given that detoxification can take anywhere from half to all of a 30-day time period, ending the program then does little more than give the patient a brief break from their acting out. Tossed back into the same environment and life-situation that they were in before treatment, with no new coping strategies for the stresses that that brings, relapse becomes all too likely.

The Psychological Reasons Why a Longer Stay in Rehab is Better

In any addiction, there is often an element of psychological dependence as well as physical dependence. The high of the addiction is often being used as a coping mechanism for underlying emotional problems. For recovery to stick, these issues have to be discovered and addressed.

In rehab, this is often done with the aid of a counselor. In order for the process to be effective, however, a relationship of trust must be established. Like detox, this, too, takes time. Then there’s getting adjusted to the environment of the treatment center. It is only after this that the deeper work of recovery can begin,

Often, the psychological dependence began as a coping mechanism for childhood trauma. As memories of these incidents surface, or the patient finds themselves in situations that are in some way reminiscent of the original incident, it triggers the emotional centers of their brain to go into panic mode, which, in turn, triggers the need to use.

By talking through these issues with a counselor, the patient undergoes what psychologists call “reprocessing.” This is the same principle behind the practice of sharing one’s spiritual inventory in a 12-step group; by reliving the traumatic event in a safe, controlled way, the patient’s emotional brain has a chance to learn a new way to respond, lessening the need to self-medicate with drugs.

Finally, as the patient prepares to reenter society, he or she must develop a new set of life skills that will enable them to navigate through life without having to rely on drugs. This is also done with the counselor’s help, and can really only be effective if done after all the other steps outlined above.