Both methadone and buprenorphine are FDA-approved long-acting opioid drugs used to treat opioid dependence through a medication-assisted treatment plan that includes both pharmacological and therapeutic methods. Opioid drug abuse and addiction constitute a massive public health crisis in the United States. The Substance Abuse and Mental Health Services Administration (SAMHSA) publishes that close to 4.5 million people in the country abused opioids in the month prior to the 2014 National Survey on Drug Use and Health (NSDUH) and almost 2 million battled opioid drug addiction.
Opioid drugs are prescribed as effective pain relievers; however, their use can be habit-forming. Misuse of opioids can create a euphoric and addictive “high,” making them prime targets of abuse. Medications like Suboxone (a combination buprenorphine product) and methadone are both regulated by the Controlled Substances Act (CSA) by the Drug Enforcement Administration (DEA). Methadone is considered to have a higher risk for diversion, abuse, and addiction, and it is therefore classified as a Schedule II controlled substance while buprenorphine products like Suboxone are classified Schedule III.
Both methadone and Suboxone can be useful tools during an opioid addiction treatment program when used as directed and as part of a complete treatment plan; however, both have possible risks and side effects as well.
Specifics of Methadone
Methadone is marketed under the brand names Methadose, Diskets Dispersible, Dolophine, and Methadone HCl Intensol in tablet, liquid, tablet for suspension, and solution formulations, Mayo Clinic reports. Methadone is a long-acting opioid analgesic that is also used to treat chronic pain that requires around-the-clock management on a long-term basis. When prescribed for the treatment of opioid dependence, it is dispensed through federally regulated clinics usually once a day.
Since its half-life is much longer than most other opioids of abuse (like heroin, fentanyl, hydrocodone, and oxycodone, for instance), it is often used to help a person wean off opioid drugs, avoid difficult withdrawal symptoms and minimize cravings as a component of a medical detox program. It may also be used for medical maintenance of opioid dependence as a replacement for illegal and opioid drugs often abused by injection, such as heroin.
Methadone is a full opioid agonist that can still be abused and has a risk for dependency in and of itself, however. The DEA publishes that as of 2012, nearly 2.5 million people in the United States admitted to misusing methadone at least once in their lifetime. Methadone abuse can lead to physical dependence and addiction as well.
Buprenorphine and Suboxone Information
Buprenorphine brand name products include Subutex, Butrans, Buprenex, Suboxone, Bunavail, and Zubsolv, which come as tablets, filmstrips, sublingual tablets, or as a patch. Buprenorphine products such as Suboxone may be prescribed by medical providers in an office setting and dispensed out of a doctor’s office or local pharmacy instead of through specially regulated clinics like methadone, per the FDA.
Suboxone is a combination product that contains both the long-acting and partial opioid analgesic buprenorphine and the opioid antagonist naloxone, usually in a 4:1 ratio. Naloxone blocks opioids from filling up opioid receptors in the brain, and generally, the naloxone component of Suboxone will not be activated unless a person tries to alter the medication and then abuse it by injection. If Suboxone is abused in this way, the naloxone will essentially “kick out” the opioid drugs from the brain, rendering them ineffective.
Buprenorphine is also only a partial agonist, meaning that it doesn’t fully activate the opioid receptors in the brain the same way that full agonists do. After a certain amount of the drug is taken, it also reaches a plateau, and no matter how much more of it is taken, it will no longer have any agonist effects.
Suboxone is generally used a little later in an opioid dependence treatment program and not as a direct opioid replacement. Instead, it will need to be taken after all other opioid agonists are completely out of the bloodstream, usually after detox, in order to ensure that the naloxone component does not precipitate withdrawal symptoms. The naloxone component and “plateau effect” are believed to work as abuse-deterrents, although it is still possible to abuse Suboxone and potentially suffer from addiction involving buprenorphine.
Abuse and Addictive Potential of Methadone and Suboxone
While both buprenorphine and methadone may be prescribed to treat chronic pain, Suboxone is primarily a medication approved to treat opioid dependence. The DEA reports that methadone is typically abused at rates higher than buprenorphine products; however, both are diverted and misused.
On the street, methadone is called fizzies, chocolate chip cookies, or amidone, while Suboxone is often referred to as stop signs or prison heroin. Suboxone and buprenorphine products are regularly abused within the US prison system by inmates, The New York Times warns, as these products can be easily disguised and smuggled into jails. Suboxone can still produce a “buzz” that is generally not considered to be as powerful as the high created by full agonists (including methadone), but it can still be desirable for individuals who struggle with opioid dependence and addiction.
When someone is dependent on an opioid drug, chemicals in the brain are changed, and when these drugs process out of the body, withdrawal can occur. Opioid withdrawal is not usually life-threatening, but the physical side effects are uncomfortable and mimic those of the flu. Emotions are also negatively impacted by opioid withdrawal, and depression, anxiety, sleep difficulties, trouble thinking clearly, and irritability are common.
Suboxone may also be misused in an effort to self-medicate these opioid withdrawal symptoms and cravings, but it is also habit-forming. This practice may only serve to deepen the dependence and therefore the duration and intensity of withdrawal in the long run. In addition, abuse of Suboxone can precipitate withdrawal, which means it can induce withdrawal symptoms to start more rapidly and be more intense than they would have been on their own.
As methadone is a full agonist, and buprenorphine only a partial agonist, methadone is likely more addictive than Suboxone; however, both carry the risk for abuse, dependence, and addiction. Physical dependence sets in with chronic use or misuse of an opioid drug. While dependence is generally a factor in addiction, it does not mean a person is necessarily addicted.
Behavioral changes, including compulsive drug use, inability to control how often and how much of the drug is taken, taking the drug despite known consequences, and impairment of daily life functioning as a result of drug abuse, are all side effects of long-term methadone or Suboxone abuse and addiction.
Potential Pitfalls of Methadone and Suboxone
Both methadone and Suboxone carry a real risk for fatal overdose. Prescription opioids accounted for over 33,000 fatal overdoses in 2015, the Centers for Disease Control and Prevention (CDC) reports. Methadone overdoses are declining (down just over 9 percent from 2010 to 2015), which may be related to the fact that the drug is being prescribed less for pain and is being more closely monitored when used for opioid dependence treatment. Buprenorphine overdose deaths are more rare, but the prescribing information for Suboxone warns that overdose may occur and can be fatal, especially if the medication is taken intravenously or in conjunction with benzodiazepines or other central nervous system depressant drugs or substances (like alcohol, for example).
Methadone has a long elimination half-life of 8-59 hours, the FDA reports, but the analgesic properties usually wear off in 4-8 hours. This may entice a person to take more before the entire dose of the drug is out of the system, which can lead to toxic overdose. Respiratory depression, sedation, cardiac complications, coma, and even death may be the result of an opioid overdose.
When used as intended and directed while under the watchful eye of a trained medical professional, both methadone and Suboxone can be effective tools for the treatment of opioid dependence. Methadone may be beneficial during detox to replace opioids like heroin and mitigate withdrawal symptoms. Suboxone can help individuals to remain compliant with treatment and abstinent while helping to manage withdrawal symptoms and cravings, and working to minimize instances of relapse. Suboxone may have less potential for abuse than methadone due to its abuse-deterrent properties.
Neither methadone or Suboxone should be used as a standalone treatment for opioid dependence. Instead, they should be part of a treatment plan that also includes behavioral therapies, counseling, and supportive care.