Reverse tolerance, also known as drug sensitization, is, in essence, the opposite of physical tolerance to intoxicating substances. Traditional tolerance develops when frequent drinking or drug use changes the brain’s structure and function, and metabolism adjusts to the constant presence of drugs or alcohol. This effect results in a person requiring increasingly higher doses to achieve the sought-after results.
On the other hand, reverse tolerance occurs when a person starts to become intoxicated on smaller doses of a substance. Researchers have linked reverse tolerance to alcohol, opiates, nicotine, and antidepressants to specific glutamate receptors in the brain. These receptors have been associated with the development of physical tolerance to drugs and alcohol, as well.
Causes of Reverse Tolerance
When people use alcohol or certain drugs in excess, their tolerance will usually increase. The liver, however, is not what becomes more tolerant of higher doses of substances such as alcohol. Thus, gradually, over time, it may no longer produce an adequate amount of enzymes, proteins that serve many vital functions.
This development is caused by the fact that many cells essential for breaking down alcohol have been destroyed. Therefore, a decline in liver function leads to reduced tolerance and may be a hallmark sign of late-stage alcoholism in a chronic alcohol abuser.
Other Forms of Tolerance
Most people are unaware there are several forms of tolerance to substances that can develop, each of which has some effect on the addiction process. It is true that tolerance often drives many addiction-susceptible people to use increasing amounts of a substance to satisfy their needs. However, there is more to it. The following describes six other forms of tolerance.
When acute tolerance occurs, the brain and CNS (central nervous system) enact processes to reduce the effects of a substance immediately. A typical example is nicotine. Nicotine use can cause acute tolerance, but, in some instances, it may increase tolerance throughout the day for those who smoke it.
Other examples include hallucinogens, such as LSD, magic mushrooms, etc. During acute tolerance, in most instances, the effects of these drugs will be diminished by a decrease in receptor sites in the brain related to a specific substance of a particular class of substances.
Individuals who are prolific drug or alcohol users may develop behavioral tolerance. This form is characterized by changes in appearance and behavior to conceal the severity of their substance abuse. Some long-term, excessive substance users have become adept at rapidly appearing to be when they encounter a threat, such as that posed by law enforcement.
This improved state of functioning may then regress when the perceived threat is gone. This effect can also occur when a person who is intoxicated encounters unexpected dramatic or traumatic circumstances. In this situation, the brain can refocus itself on the threatening event, and the high will be diminished or eliminated.
These effects are reminders that the human brain is a remarkable organ that is proficient at rapidly acclimating to various chemical interferences and circumstances. It is believed that behavioral tolerance is facilitated by regions of the brain unaffected by substance use that allow the person to recover from the effects of being intoxicated, at least temporarily.
The brain cannot dispose of psychoactive drugs and alcohol on its own. In most cases, the brain depends on the interaction between neurochemicals and receptors, but some substances can interrupt this process, which results in the brain becoming powerless to respond.
Regarding dispositional tolerance, the body is obligated to accept this responsibility. It achieves this by boosting metabolic rate so that blood can circulate the toxic substances more rapidly for the liver to expedite the elimination process. This action reduces the effects of the substance. Similar to what we think of as normal or traditional tolerance, the user requires increasing use of the substance to experience the desired results.
Inverse tolerance is a somewhat strange effect and is not wholly understood. This type of tolerance has two primary characteristics that make it challenging to investigate and understand. Inverse tolerance is basically the same thing as what is known as the Kindling Effect. This effect is linked to changes in the brain and CNS regarding how chemicals are processed.
When a person struggles with addiction quits and relapses several times, they are at risk of developing kindling. This condition is characterized by a worsening of withdrawal symptoms each time the individual attempts to discontinue substance use, which can dramatically impact recovery efforts. Alcohol is a common substance associated with the Kindling Effect.
Pharmacodynamic tolerance occurs when the brain begins to enact processes intended to diminish a foreign substance’s effects. For example, nerve cells, receptor and reuptake sites, and transmission processes can be altered by the brain to increase desensitization to a substance. This action can serve as a sort of intoxication antidote by distributing the chemical across a broader field of sites, therefore mitigating the effects.
Like inverse tolerance, how select tolerance occurs is not fully understood. However, it refers to the fact that, in some cases, the brain will mitigate some of the effects a substance induces, but it may not affect all of them. For example, some individuals who smoke marijuana for an extended period will become less able to achieve feelings of euphoria. This occurs despite the fact that other parts of the body, such as the throat, lungs, and cannabinoid receptors, are still being affected.
This condition could be hazardous in instances in which increasingly higher doses of a substance are being used to compensate for the development of a select tolerance to a particular substance. Moreover, a heroin user may not be experiencing the “high” they are seeking, and yet the drug continues to have wreak havoc on other parts of their body.
When users engage in this behavior, they place themselves at an increased risk for overdose because they are oblivious to the fact that toxicity levels are higher than they seem.
All Forms of Tolerance Can Be Harmful and Hazardous
The main problem with most forms of tolerance is that their development prevents the body from functioning correctly. As a result, addicts are often encouraged to consume more of a substance as they try to circumvent the effects of tolerance. Such action serves to perpetuate an escalating pattern of abuse that requires intervention as soon as possible.
Unfortunately, even people who use prescription drugs, sleep aids, or other chemical-based therapeutic medications are susceptible to the development of various forms of tolerance, as well as and dependence and addiction.
Getting Help for Addiction
If you or someone you love are suffering from drug abuse and tolerance, we urge you to seek professional help as soon as possible before the problem worsens. Addiction is now considered to be a lifelong, potentially relapsing disease, but, fortunately, it can be treated effectively, and harm done can be reduced. Individuals who experience this condition need evidence-based, professional help in the form of behavioral therapy, counseling, and group support.
Just Believe Recovery offers integrated treatment programs that address substance abuse, mental health disorders, and the underlying causes of addiction. We aim to provide those we treat with the education, tools, and support they need to succeed at recovery and promote long-term sobriety and wellbeing.
If you are ready to begin your recovery journey and reclaim the healthy and fulfilling life you deserve, contact us today to find out how we can help!