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Agonist vs Antagonist Drugs

Written by Shannon Weir, RN | Updated on Sep 28, 2023

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Medically reviewed by Dr. Patrick J. Gallus, DO

As you search for the right detox treatment, you may come across terms that you are not familiar with. Understanding drug addiction and how different drugs work in the body is important for long-term recovery. With a high dose methadone detox program, you can begin the recovery process in a safe, comforting environment.

How Agonist vs Antagonist Drugs Work

Most addictive drugs fall into two categories that are based on the way drugs are effective, which means that the drug is either agonist vs antagonist drugs. An agonist drug is one that works to imitate the effects of the brain’s neurotransmitter, while an antagonist works to block the brain’s neurotransmitters.  In addictive drugs, such as opiates, dopamine is the most targeted neurotransmitter. The release of dopamine is the reason for the euphoric feeling.

Direct and Indirect Binding Agonists

Agonists fall into two types: direct binding and indirect agonist. A direct binding agonist is one that attaches directly to the receptor sites and acts like a neurotransmitter. One example of a direct binding agonist is the drug apomorphine, which binds to dopamine receptors. The result is that the user experiences the same effects as if dopamine was released in the brain. An indirect agonist increases and enhances the amount of neurotransmitters affected, but has no specific agonist activity at the receptor. In short, an indirect agonist achieves its effect by working through other means. An example of an indirect agonist is Cocaine.

Direct and Indirect Antagonists

As in agonist, antagonists fall into two categories: direct and indirect acting antagonists. A direct acting antagonist binds to and blocks neurotransmitter receptors, preventing the neurotransmitters themselves from attaching to the receptors. An example of this is the drug Atropine. An indirect antagonist prevents the production or release of neurotransmitters. An example of an indirect antagonist is the drug Reserpine, an anti-psychotic medication that treats psychotic symptoms and high blood pressure.

Suboxone, Methadone, and Naltrexone

Suboxone, Methadone, and Naltrexone are drugs used in addiction treatment. Specifically, Suboxone is a combination of buprenorphine, an opioid medication and partial agonist, and naloxone, also a narcotic and antagonist, which works to reverse the effects of other drugs. Suboxone is an agonist and opioid blocker. Moreover, a Suboxone detox program is a safe way to reduce withdrawal complications.

Methadone is another drug that is common in drug detox treatment. Methadone works as an opioid agonist and will reduce physical withdrawal symptoms and cravings during detox from other opiates. Moreover, if you use other opiates while taking Methadone, it will block the euphoric effects of opioid abuse.

Naltrexone is an opioid antagonist that blocks the receptors and prevents the euphoric effects from using opiates. Unlike Suboxone and Methadone which are taken for drug detox, Naltrexone is taken after the individual stops using opiates. Naltrexone should not be used while the individual is still using opiates, as it can result in severe side effects. While Naltrexone will reduce cravings – as will Suboxone and Methadone – it will not treat withdrawal symptoms, nor will it prevent opiate use.

To find out more about agonist vs antagonist drugs detox medications, call Gallus Detox Center at (888) 306-3122. Take the first step in overcoming drug addiction and call us today.

Shannon Weir, RN

Shannon Weir, RN is the Chief Nursing Officer at Gallus Medical Detox Centers. She has been a Registered Nurse for 30 years, Shannon’s experience ranges from critical care to flight nursing, medical detox, sexual assault exams, and SWAT nursing. Shannon has been with Gallus Medical Detox Centers since 2010 and is a vital part of our organization.

Last medically reviewed on June 17, 2016

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Dr. Patrick J. Gallus, DO
Mar 26, 2024
Dr. Patrick J. Gallus, DO
Mar 25, 2024
Dr. Patrick J. Gallus, DO
Mar 20, 2024

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