Opioid Replacement Therapy Risks: Methadone vs Buprenorphine
Is Opioid Replacement Therapy really safe?
That’s a difficult question, with shades of meaning that depends on the definition of “safe”. To answer the question fully, let’s examine the practice of Opioid Replacement Therapy more closely.
What is Opioid Replacement Therapy?
Opioid Replacement Therapy (ORT) is a medical treatment where a patient addicted to heroin or prescription painkillers is given a less-euphoric opioid under medical supervision. It can also be referred to as Opioid Substitution Therapy, or OST.
The two most-commonly-prescribed medications are methadone and buprenorphine. When prescribed and taken correctly, each of these medications ease withdrawal symptoms and reduce cravings. However, they DO come with certain limitations and risks.
The idea of using “safer” opioids to treat opioid addiction is based on the idea that chronic drug abuse profoundly alters the user’s brain. The cravings, drug-seeking, and abuse of opioids becomes a “bio-behavioral” compulsion.
Proponents believe that replacing dangerous illicit drugs with safer legal ones and dirty needles with medically-dispensed pills, films, and liquids reduces the harm to both addicts and society.
ORT’s main focus is NOT specifically to enable the patient to live a completely drug-free life. Rather, it is to allow the former drug addict to live a safer life, one with a greater degree of stability and normalcy. This is why ORT is known as a “harm reduction” strategy.
For those patients who are motivated to move totally away from drugs, their medication can be very gradually tapered, while other types of addiction treatment are utilized.
Benefits of Opioid Replacement Therapy
The World Health Organization, the Substance Abuse and Mental Health Services Administration, the United Nations Office on Drugs and Crime, and the Joint United Nations Program on HIV/AIDS all support ORT. ORT gives opioid addicts a chance to gradually wean from other, more dangerous opioids without experiencing debilitating withdrawal symptoms. Other ways that ORT reduces harm include:
- Up to two-thirds of opioid addicts receiving ORT are able to totally abstain from illicit opioid abuse
- 70%-95% significantly reduce their opioid use
- Medically-assured purity, quality, and dosage
- Daily attendance at a maintenance clinic gives addicts structure, a necessary component of recovery
- Reduces the spread of Hepatitis and HIV, because it allows IV drug abusers to stop using needles
- Encourages drug addicts to enter drug treatment programs
- Lower crime and incarceration rates
- Improves quality of life – ability to hold a job, maintain relationships, etc.
Methadone – the Risks
Although methadone is considered to be safer than heroin, it is an extremely potent opioid –5X stronger than morphine – that carries risks all its own:
- Methadone accounts for just 2% of all opioids prescribed for pain, but is involved in over 30% of all prescription opioid-related deaths.
- Methadone is 4X more likely to cause a fatal overdose than oxycodone.
- It is TWICE as likely to cause a fatal overdose as morphine.
- Pain relief – one of the major components of a methadone maintenance program – only lasts between 4 and 8 hours, but the drug’s dangerous respiratory depression effects last up to 59 hours.
- 40% of single-drug prescription overdose deaths are because of methadone.
- This is TWICE as many as any other prescription pain medication.
- In 1999, 790 people died because of methadone.
- Today, there are approximately 5000 methadone-related deaths annually.
When considering only the mortality risks associated with time spent in methadone maintenance programs, there are a few things to consider.
- Among opioid addicts, ORT using methadone DOES result in a significant decrease in mortality rates, compared to no treatment at all – dropping from 36 deaths/1000 person years to 14 deaths/1000 person years.
- However, this rate is much higher than it should be, because of specific points of methadone ORT – very early in ORT, and immediately following cessation of treatment.
- 21% of methadone deaths during ORT occur in the first week of treatment.
- 88% of those deaths involved methadone in combination with some other substance, usually another central nervous system depressant such as alcohol, benzodiazepines, tranquilizers, or other opioids.
- Overall, the mortality risk during the first four weeks of ORT is a comparatively-high 11 deaths/1000 person years, dropping off considerably after that, for the remainder of treatment.
- The mortality risk more than triples out of treatment, especially during the first four weeks immediately following cessation – over 32 deaths/1000 person years.
Buprenorphine – A Better Alternative?
“The process of craving opioids itself causes people to be so one-dimensional that it is a defect itself. Freed from the obsession to use, people change.”
~ Dr. Jeffrey T. Junig
Buprenorphine is rapidly increasing in popularity as a ORT medication. In 2014, 60%-65% of patients receiving any medication-assisted treatment were prescribed buprenorphine, either alone or with naloxone, in a combination product called Suboxone.
That number is expected to rise sharply, because in December 2016, the United States Department of Health and Human Services made the announcement that it was raising the limit on the number of patients allowed to receive buprenorphine to 275 per qualified provider. The previous limit was just 100 patients.
A Few Words About Suboxone
The addition of naloxone in this formulation helps deter abuse. In fact, at high doses, Suboxone can trigger withdrawal in someone addicted to opioids. According to the US Institute on Drug Abuse, Suboxone is a first-line treatment medication for opioid dependence.
But there is a caveat – the naloxone in Suboxone is only effective when the medication is taken orally. If the drug is misused intravenously, the naloxone is NOT metabolized, resulting in an opioid high.
This is a legitimate concern, because Suboxone is prescribed for at-home use, unlike methadone. Patients taking methadone at a clinic must demonstrate a significant period of sobriety and program adherence, before there is even a possibility of a take-home prescription.
Advantages of Buprenorphine
Even though buprenorphine is far more potent than methadone – up to 30X stronger than morphine – it is a partial-agonist, giving it several advantages over methadone, a full agonist.
Whereas the effects of methadone increase with dosage, buprenorphine’s affects level off at a plateau, meaning it has a “ceiling affect” that does not increase, even with increased dosage.
In other words, a person given buprenorphine cannot get high from ANY opioid.
This is key when it comes to preventing overdose deaths. Because of the ceiling effect, the risk of respiratory depression from opioid overdose is much less than that from methadone. For comparison, in 2011, the American Association of Poison Control Centers reported only 3 deaths due to buprenorphine.
However, it IS still possible to overdose from a polydrug combination of buprenorphine and other CNS depressants such as alcohol or benzodiazepines.
But buprenorphine SAVES lives. In France, use of buprenorphine reduced heroin mortality by 50%. Likewise, Baltimore realized a 37% heroin mortality decrease because of the medication.
When considering only the mortality risks associated with time spent in opioid replacement treatment, buprenorphine also reduces “any cause” mortality. However, as is the case with methadone, the risk of mortality rises sharply during the first four weeks after treatment stops, compared with the remaining time spent out of treatment, nearly tripling – 11 deaths/1000 person years to 32 deaths/1000 person years.
But UNLIKE methadone, there is virtually no difference between the initial four weeks of treatment and the duration of treatment. In other words, simply commencing ORT using buprenorphine does not automatically increase the mortality risk.
Limitations of Buprenorphine
The biggest criticism of buprenorphine is the fact that its ceiling effect means that at low doses, it is not as effective as methadone at satisfying the cravings and withdrawal symptoms experienced by individuals who are accustomed to very high doses of heroin.
At medium and higher dosages, however, buprenorphine and methadone are equally effective.
Of Special Interest to Pregnant Women
Among pregnant heroin abusers, buprenorphine abuse to be a much safer option for ORT than methadone. A 2008 study shows that compared to methadone, buprenorphine ORT results in:
- Longer gestation
- Higher birth weight
- Shorter hospital stays
- A much lower incidence of neonatal abstinence syndrome (NAS) – 40% versus 78%
- Of those infants born with NAS, only 15% of those whose mothers used buprenorphine needed withdrawal treatment, while 53% of those whose mothers used methadone did
Significantly, when ORT using buprenorphine begins matters. When buprenorphine ORT commences before conception, the rate of NAS is 26%, while starting ORT after conception causes the NAS rate to jump to 60%.
Moving On from ORT
One of the most profound differences between using either methadone or buprenorphine during ORT is the fact that buprenorphine can be discontinued at ANY time, whereas methadone dosages must be slowly reduced.
This has strong implications for anyone who wants to move forward in recovery completely substance-free. ORT, like any form of medication-assisted treatment, is a valuable recovery tool for those who need it. But for those who are motivated to achieve total abstinence, ORT should only serve as temporary support, until they are able to stay sober on their own.