Drug Tolerance: What It Is And Why It’s Dangerous

Almost every article about substance abuse makes reference to terms like “dependence”, “addiction” and “tolerance”. However, you may not be sure what these words mean or how they relate to you or your loved one’s problems with drugs or alcohol. In this article, we’ll take a close look at drug tolerance, how it relates to dependence and addiction, and why seeking professional treatment for substance misuse and addiction is so important.

What is the Definition of Drug Tolerance?

According to the National Institute on Drug Abuse, drug tolerance is “a state in which an organism no longer responds to a drug”. It usually occurs when a person repeatedly uses alcohol or drugs, including some prescription medications.

As time goes on, the body stops responding to the substance in the way it did the first time the individual used the substance. Where illicit drugs or alcohol are concerned, the brain may not experience the euphoria it once did.

The time it takes for tolerance to develop and the degree of tolerance a person experiences vary depending on several factors. For example, some drugs lead to tolerance faster than others while genetics help to determine how an individual’s body will react to substances.

When people use drugs or alcohol in an effort to achieve euphoria or intoxication, the phenomenon of tolerance drives them to use larger amounts or use them in riskier ways. Therefore, a person who developed a high tolerance to heroin by smoking it may start injecting it.

A person who no longer feels the effects of beer may consume multiple shots of liquor in a short period so they can get drunk. Some people also mix various types of substances to get the effects they want after tolerance to one drug develops. All these actions increase the risk of negative side effects including overdose.

Adderall addiction treatment, as shown by Adderall pills spilling from prescription container

Drug Tolerance Vs Dependence

You may be wondering about the difference between drug tolerance and drug dependence. There are certain receptors in the body that activate in the presence of specific substances. When tolerance develops, those receptors don’t respond in the same way anymore. That’s why individuals don’t experience the effects they once did.

In contrast, when a person becomes dependent on a substance, the body only functions normally when the substance is present in the usual amount. Therefore, the individual may experience withdrawal symptoms if they stop taking the drug or they suddenly reduce their dosage.

Withdrawal symptoms vary depending on which drug is involved and they can range from mild to severe. Withdrawal from some substances can be life-threatening in the absence of medical support.

Tolerance and dependence can lead to addiction. This is a chronic disease that is characterized by compulsive drug or alcohol seeking and continued usage despite negative consequences. People who are addicted to substances need to seek professional help to achieve and maintain sobriety.

Types of Tolerance

Tolerance can take several different forms.

Acute Tolerance

This refers to the process by which the brain and central nervous system act immediately to mitigate the effects of a particular substance. Tolerance typically develops over several weeks but some drugs can cause a rapid onset.

The substances which are most likely to cause acute tolerance are nicotine and hallucinogens such as mushrooms, DMT, Ecstacy, and LSD. Cocaine and antidepressants can also lead to tolerance with just one dose.

Pharmacodynamic Tolerance

This is when the brain actively works to mitigate the effects of a foreign substance. The brain can adjust nerve cells, reuptake and receptor sites, and transmission processes to permit desensitization.

What essentially happens is that the brain produces an antidote to the substance or increases the number of receptor sites so as to diffuse the substance more widely and lessen the effects.

Select Tolerance

A lot is still not known about this type of tolerance. However, select tolerance refers to when the brain mitigates only some effects of a substance. For example, some people who use heroin may stop getting high but other parts of the body may be severely affected. Select tolerance can be dangerous if a person takes higher doses of a substance in an attempt to experience euphoria. Without realizing it, they could be setting themselves up for a deadly overdose.

Behavioral Tolerance

Long-term substance users often learn how to demonstrate behavioral tolerance. This is when they adjust their actions, appearance, and mannerisms to hide their drug use. Some people can suddenly appear sober in the face of a threat such as an authority figure and then go back to appearing high once the threat has passed.

An individual who is high may also be temporarily able to focus on a sudden or dramatic event. In the presence of a threat, the high diminishes or is eliminated. With behavioral tolerance, the areas of the brain which aren’t affected by the substance in question are engaged when necessary and then they revert to their normal state.

Dispositional Tolerance

This refers to when the body’s ability to dispose of a substance is enhanced after repeated use. The kidneys may excrete the drug into the urine more readily or the liver may break it down more easily.

In either case, a smaller amount of the drug reaches the crucial parts of the body, and the effects are, therefore, diminished. Individuals need to take larger doses if they want to achieve the effects they once did.

Inverse Tolerance

This phenomenon is pretty much the same thing as the Kindling Effect. It is not well understood but it involves changes in the way chemicals are processed by the brain and central nervous system. The body becomes either sensitized or desensitized to a particular substance. If long-term alcohol use harms the liver, the body will be less able to process alcohol.

This can lead to sensitization where the body becomes more vulnerable to the effects of alcohol. Meanwhile, desensitization occurs when the effects of a substance become more intense. Inverse tolerance can worsen the severity and duration of withdrawal symptoms.

Reverse Tolerance

Reverse tolerance refers specifically to the increased sensitivity an individual may experience toward a particular substance because the body is unable to process the substance. This phenomenon usually occurs in people with chronic alcoholism whose livers have ceased to function normally. This means alcohol remains in the blood longer and at higher concentrations, leading to significantly increased sensitivity.

Drug Tolerance and Prescription Drugs

Where prescribed medicine and tolerance are concerned, tolerance isn’t always a negative thing. It can be a normal adaptive response to repeated use of a particular medication since the body is always striving to achieve and maintain homeostasis.

If a medication loses its effectiveness over time, tolerance will be considered negative. However, tolerance can also be positive. Think of how unwanted side effects such as fatigue or nausea often go away over time or how allergy shots manage to be effective. This is all due to the development of tolerance.

Some medications are more likely to lead to tolerance than others. Most often, these are drugs that affect the brain and nervous systems such as opioid painkillers, over-the-counter sleeping aids such as Benadryl, and sedatives including valium. If a patient becomes dependent on a drug, their doctor will usually come up with a tapering schedule so they can gradually ease off the drug. This helps to prevent withdrawal symptoms.

Drug Tolerance

Risks of Developing Drug Tolerance

The main danger associated with most types of drug tolerance is that the body doesn’t function as it normally would. People who are addicted to drugs or alcohol are, therefore, driven to use more and more to offset the effects of tolerance. This leads to a dangerous cycle that can be very hard to break since the body will eventually become accustomed to each new dosage.

Even people who are using prescription painkillers or sleep medications can develop tolerance if they continue using.  Developing drug tolerance can lead to:

  • A flare-up in symptoms if medication becomes less effective
  • An increase in negative side effects if larger doses are needed for symptom relief
  • The development of a substance use disorder
  • A cross-tolerance to other drugs
  • Overdose
  • Addiction

Tolerance and Seeking Drug Treatment

Regardless of whether you’re using prescribed medications or illicit substances, you need to seek help at the earliest opportunity if you feel you need to take increasingly larger doses. Otherwise, you could develop an addiction to the substance you’re using.

Talking to an addiction treatment professional will ensure you’re accurately diagnosed, and you get the help you need.

Very often, substance abuse treatment begins with detoxification. Prolonged use of drugs or alcohol will result in a buildup of toxins in the body. The detox process rids the body of these toxins and prepares the mind and body for rehabilitation. During detox, individuals are likely to experience uncomfortable withdrawal symptoms. These may include:

  • Muscle aches
  • Nausea
  • Vomiting
  • Diarrhea
  • Insomnia
  • Sweating

Depending on the drug involved, these symptoms can be dangerous, painful, and/or life-threatening. In such situations, individuals are strongly advised against attempting to detox at home alone. Instead, it’s recommended that they enter a treatment center and undergo medically supervised detox.

Withdrawal symptoms vary considerably from one individual to another based on their history of drug use or abuse, health status, and other factors. However, having medical personnel on hand 24/7 ensures the process is as safe and comfortable as possible.

They can provide medication and other interventions aimed at minimizing both the physical and psychological effects of withdrawal.

Notably, completing detox brings an end to drug tolerance. If the individual takes the drug again, the effects could be very dangerous especially if they take the dosage to which they were previously accustomed. This can easily lead to overdose. People who complete detox and relapse immediately are at much higher risk of fatal overdose.

This is why addiction treatment professionals usually recommend that individuals go straight into rehabilitation when they complete detox. Detox isn’t enough to ensure long-term sobriety.

People who have become addicted to a substance need to learn how to cope with triggers and manage difficult emotions without turning to drugs or alcohol. This is the only way they can remain sober.

For many people, residential treatment is the best option but others benefit from less intensive programs such as partial hospitalization or some form of outpatient therapy. Even after this, individual counseling and peer support groups can be invaluable. Developing the skills for tolerating long-term recovery is extremely important.

Get the Help You Need with Find Addiction Rehabs

If you’ve been prescribed medication by a doctor and it is no longer working, you should contact that physician. It’s possible that you may have developed a drug tolerance. Your doctor will be well-placed to determine what the next steps should be. Depending on the severity of your condition, they may refer you to an addiction treatment professional.

However, it can be very difficult to know where to turn when you need help in overcoming your dependence on alcohol or illicit substances. You can still begin by talking to your doctor.

With more severe dependence and addiction disorders, it is likely you will need specialist care and need access to the widest range of options possible. You don’t have to be afraid or ashamed to reach out to experts who are trained to help.

By contacting Find Addiction Rehabs, you can be provided with a list of treatment centers that cater to people with your specific requirements and preferences. Fill out the contact form on our website or call us at any time of the night or day and we’ll do everything we can to help you.

In some situations, we can place individuals in a facility within 24 hours. Drug tolerance, dependence, and addiction don’t have to ruin your life. Get the help you need and deserve today!

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