Dependency upon a certain substance is feeling the need to take the drug in order to feel better. It is the persistent and compulsive use of a substance that can result in developing a tolerance to the drug. A dependency can slowly grow when someone feels like without the drug he or she would not be able to be psychologically healthy or happy. A psychological, and often physical, dependence grows upon a substance that has consistently created feelings of euphoria, or at the very least, feelings of contentment from feeling loss or depressed without the drug.

As mentioned, a dependency can lead to tolerance. Developing tolerance is when a person’s body and mind become more and more accustomed to the substance, such that they need more of the drug to produce the same high. Both dependency and tolerance are significant indicators of an addiction, and when a person experiences dependency and tolerance, there can be serious medical and psychological implications.

Cross dependency is the dependence upon one drug that gets transferred to another drug of a similar class. For instance, if someone is taking prescription drugs and he or she begins to take heroin, the dependency will continue to grow regardless of the drug he or she is taking because of both these drug types are opiates. Dependency is evident when a person uses a different drug in order to alleviate withdrawal symptoms from use of the first drug. For instance, when a person uses cocaine but switches to heroin to feel better while coming down from cocaine use.

Cross dependency is sometimes used in favor of treatment. For instance, when a person is being treated for an addiction to heroin, he or she may given controlled weekly doses of methadone, which is also an opiate, as a means alleviating heroin withdrawal symptoms. The aim of the treatment is to slowly wean a person off the drug while providing education on healing addiction, therapy, and other forms of medication, if needed.

Another phenomena similar to cross dependency is cross tolerance. This is the experience of developing tolerance to one drug while also having certain levels of tolerance to other types of drugs. For instance, if a person has a tolerance to an amphetamine, he or she might also develop a tolerance to methamphetamine. Both types of drugs are stimulants and can have similar chemical structures. For this reason, a person can develop a tolerance to both types of drugs at the same time.

If a person with cross dependency and cross tolerance were to enter drug addiction treatment, the detoxification period might be more challenging and intense. He or she will have to detox from the various drugs with which there is a dependency and tolerance. Also, tolerance and dependency usually occur only after long-term, chronic use of a substance. These experiences happen when nerve cells in the body are chemically and structurally changed as a result of extensive drug use.

If you or someone you know is struggling with a chronic addiction, contacting a mental health provider can save a life. Call a drug counselor or treatment center for assistance today.

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