Medications for Addiction Treatment

Naltrexone and Buprenorphine

The National Institute on Drug Abuseexplains that naltrexone works by blocking the receptors in the brain that opiates seek out, rendering those drugs incapable of providing the addictive high. Naltrexone is safest when used after the person has completed medically supervised detox, because using it when opioids are still in the body may cause exceptionally severe withdrawal symptoms.

Naltrexone is considered to be an “ideal”medication for treating opioid abuse, because of the ease of administration, minimal side effects, and low addictiveness and potential for abuse.

While naltrexone works by completely shutting down the opioid receptors in the brain, a drug like buprenorphine functions by partially blocking them; that is why naltrexone is referred to as an “opioid antagonist,”and buprenorphine is called a “partial opioid agonist”(meaning that it activates the brain’s opioid receptors but not to the extent that heroin does, which is why heroin is considered a “full opioid agonist”).

Since buprenorphine is a partial opioid antagonist, it does not cause the same highs as a full opioid agonist would. According to the Substance Abuse and Mental Health Services Administration, this lowers the potential for abuse, as well as the severity of the withdrawal effects once the buprenorphine works its way out of the person’s body. Used this way, buprenorphine can wean individuals off their dependence to full opioid agonists.

The Drug That Could Combat the Heroin Epidemic

On the other end of the spectrum of partial opioid antagonists like buprenorphine are pure opioid antagonists, like the drug naloxone. As Drugs.com puts it, pure opioid antagonists reverse the effects of opioids; contrasted to opioid antagonists like naltrexone that simply deny opiates access to the brain’s opioid receptors, naloxone actively undoes the narcotic effects of full opioid agonists.

This undoing can be very dangerous for patients whose addiction and dependence on opioids is severe, potentially increasing the effect of the inevitable withdrawal symptoms they will endure as they are weaned off opioids. For this reason, naloxone is often bundled with buprenorphine into a drug called Suboxone, which the Washington Postdescribed as “the drug [that] could combat the heroin epidemic.”

Naltrexone has also found applicability as a tool to treat alcoholism. An injectable, extended-release form of naltrexone known as Vivitrol has been called “the most important breakthrough in addiction treatment in the past 25 years.”A medical director tells the New York Daily News that while naltrexone requires a pill to be taken once every day or two days, Vivitrol is administered via injection once a month. According to the director, patients find this method of administration helps them remain sober.