Types Of Drug Tolerance: Metabolic, Functional, And More

Repeated drug or alcohol use causes the body to adapt over time, a process known as tolerance. As drug or alcohol tolerance builds, the same dose that once produced a noticeable effect stops working as well, pushing people to use more just to feel what they used to feel from a smaller amount.

This pattern can spiral quickly. As doses increase, so does the risk of overdose and serious health complications, and the body becomes increasingly dependent on the substance being present. Tolerance isn’t the same thing as addiction or physical dependence, but it’s often the earliest warning sign, and left unaddressed, it can lead to both.

What Are The Types Of Drug Tolerance?

Desensitization and tolerance can happen with alcohol, opiates, stimulants, benzodiazepines, prescription painkillers, and amphetamine, to name a few. Tolerance occurs when the substance of choice is used heavily and over a period of time.

Regardless of the type of substance being used, there are a few different types of tolerance that can occur.

Acute Tolerance

Acute tolerance occurs during a single use of a drug but with repeated doses and in quick succession, and oftentimes with high concentrations. This type of tolerance might occur during a drug or alcohol binge.

Behavioral Tolerance

Behavioral tolerance occurs when a person is able to hide their drug or alcohol use through certain demonstrated behaviors or in certain situations. For example, an experienced drinker may be able to maintain a sober disposition when speaking to law enforcement.

Metabolic Tolerance

This type of tolerance refers to how long a drug lasts. In some instances, the more often you use a drug and the more of it you take, the faster your body will metabolize it and get rid of it with digestive enzymes.

Learn more about metabolic drug tolerance.

Functional Tolerance

Functional tolerance occurs when a person’s brain functions become adaptive to the behavioral and bodily changes that a person exhibits while they are using drugs or alcohol. This is similar to pharmacodynamic tolerance in which a person’s brain chemistry becomes acclimated to the presence of the drug being used and loses some of its abilities.

Find out more about functional drug tolerance.

Is Tolerance The Same As Addiction?

Tolerance and drug addiction are not the same condition, though they are related and often found occurring in unison. Furthermore, tolerance can exist with or without drug dependence. Not all drugs are addictive, and some are more addictive than others, but it is generally possible to develop tolerance to any drug or alcohol when used enough. However, using a drug a lot can build a tolerance to it but not necessarily a dependence or addiction, if that particular substance does not have addictive properties.

How Drug Tolerance And Alcohol Tolerance Differ

Drug tolerance and alcohol tolerance share the same idea but work differently in the body. Alcohol is consumed and travels through the digestive system, while most drugs are smoked, snorted, or injected and typically travel straight to the central nervous system. This is why the effects and side effects of a drug are usually felt much longer than the effects of alcohol. A tolerance to alcohol is also more susceptible to certain influences, such as how much food a person has eaten prior to drinking during a particular instance.

Can Drug Tolerance Be Reversed?

Tolerance can generally be reduced, though a person may not fully return to their original baseline sensitivity. The most effective way to lower tolerance is to stop using the substance entirely, ideally for an extended period, which allows the body to gradually recalibrate.

This intentional pause is sometimes called a drug holiday. In certain cases, a doctor may even recommend one for a prescription medication to help restore its effectiveness. However, reducing or stopping any prescribed medication should only be done under a provider’s guidance, since doing so on your own can carry real risks.

Can You Treat Drug Tolerance?

Stopping a substance allows the body to gradually reset its tolerance over time, but doing this without medical support can be dangerous, especially with physical dependence involved, since withdrawal can range from uncomfortable to life-threatening.

Professional addiction treatment offers the safest path forward, addressing both tolerance and the underlying addiction driving it.

Effective treatment options include:

• individual counseling to address personal issues driving substance use
• family counseling to repair relationships and build support systems
• behavioral therapy to change thought patterns and behaviors around drug use
• medical detox to safely manage withdrawal symptoms under doctor supervision
• medication-assisted treatment to reduce cravings and ease the recovery process
• 12-step programs like AA or NA for community support and accountability
• peer support groups to connect with others in recovery
  relapse prevention training to develop coping strategies for staying sober

Browse our directory or reach out to the Substance Abuse and Mental Health Services Administration (SAMHSA) for more information about addiction recovery.