Shoreline Sober Living, San Diego, CA
Cross-Tolerance: Drugs & Substances

The term cross-tolerance refers to the state when an individual builds a level of resistance against the effects of a drug or substance that subsequently transpires to building a tolerance to other substances or drugs.

Cross-tolerance tends to occur among drugs that have similar effects due to them effecting the same cell-receptors. Separating these drugs into their own categories is known as drug classification and can be useful for identifying the risks and effects associated with each substance.

Drugs are often categorised into various types by analysing their biological compound, the effects or the associated risks. Due to there being several possibilities of how to categorize these substances, there is often much overlap causing the same drug to occur in one or more types. As a result, there is not a conclusive way to structure the different categories of drugs and substances.

Find a list below of some of the most popular occurrences of cross-tolerance among different drug classifications.






Often referred to as, ‘downers’, depressants include a series of substances including alcohol, opioids and benzodiazepines. Contrary to popular belief, depressants do not make you feel depressed, but slow down messages sent to and from the central nervous system.

These effects result in a reduction of concentration and when consumed in small doses, causes the user to feel more at ease. A study conducted by the European Journal of Pharmacology found that severe consumption of ethanol resulted in a cross-tolerance to the hypothermic effect of morphine.







Inhalants are substances that are inhaled to induce a psychoactive effect on the brain. Often referred to as huffing, the most common examples of inhalants used are paint thinners, nail polisher remover and gasoline. Cross tolerance among inhalants is rare but can be seen specifically between paint thinners and nail polisher.

Cross-Tolerance Examples

Alcohol and benzodiazepines: are one of the most common combinations seen among cross-tolerance. These two substances often come into close contact with one-another due to benzodiazepines being used to treat those suffering from severe alcoholism. Benzodiazepines are effective at treating alcohol-dependent users, as research suggests that minor amounts of benzodiazepines caused a severe reduction in the quantity of alcohol consumed. On the other hand though, benzodiazepines also pose a known threat of increasing cravings for alcohol.

Heroin and other opioids drugs: is another common example of cross-tolerance among drugs. Users of heroin often discover when using other opioids, a tolerance has been built up towards other opiate drugs, again due to these drugs all affecting the same receptors in the brain. The cross-tolerance of heroin and other opioids often leads to treatment of similar drugs including methadone in an attempt to side-track withdrawal but this methodology can often lead to a higher chance of becoming addicted to the supposed treatment instead.

The Dangers of Cross-Tolerance

The dangers of cross-tolerance can lead to taking other drugs in either higher dosages or higher quantities in order to reach the original levels of euphoria needed to get high. As a result, cross-tolerance can be extremely dangerous and anyone suffering from cross-tolerance or drug withdrawal in general should need professional medical help.

Speaking to a sober living provider in your local area can dramatically increase your chances of overcoming cross-tolerance and providing you a route to sobriety. A supportive community and around the clock care with a structured program helps increase recovery rates from drug and alcohol use substantially.

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