Buprenorphine: Treatment for Heroin and Opioid Dependency
The Federal Drug Administration (FDA) recently approved buprenorphine to treat heroin and opioid dependency in the United States. Its unique pharmacological properties offer reduced potential for abuse, diversion, and overdose, making it especially suitable for office-based practice. Buprenorphine may soon provide an important alternative to traditional opiate detoxification and maintenance therapy.
I selected this research topic because of my personal experience with heroin addiction that consumed almost 23 years of my life. During that time, I managed to fail several methadone detoxification treatment programs that resulted in me being maintained on an extremely high dose of methadone for six years. Like many heroin addicts who discover a way to buy time until their next "fix", I used methadone for the wrong reasons and ultimately, found myself with a high-tolerance addiction to heroin and methadone.
I will approach this topic first by reporting on the current situation of opioid and heroin abuse in the U.S., and describe three traditional pharmacotherapy types and the medications used in those therapies. I will then report on the history of buprenorphine, pharmacology, side effects, abuse potential, and effectiveness. I will conclude this report by summarizing the available information, and without a bias opinion because of my personal failures with methadone, compare buprenorphine to existing treatment medications.
Abuse of opioid drugs, from painkillers such as Vicodin and Oxycontin to street heroin, is a serious problem that continues to grow. According to the Federal Substance Abuse and Mental Health Services Administration 2004 (SAMHSA), in the year 2003, about 1.4 million people were dependent on prescription pain relievers and nearly 12 million people used drugs for nonmedical reasons (Kranzler and Ciraulo 56).
A survey performed by the National Survey on Drug Use and Health (NSDUH) found that 1.6% of the U.S. population over the age of 12 years reported heroin use at some time in their lives. In urban areas heroin use among men is approximately three times that of women. In 1990, use increased with the availability of inexpensive, high quality heroin. From 1999 to 2000, heroin-related emergency room cases in the U.S. increased 15%. In 2003, the NSDUH indicated that approximately 119,000 Americans reported current heroin use. Approximately 90% of heroin abusers are predominantly white and more than 50% are employed full-time, and almost 89% have a high school diploma or higher education. Reports show that the greatest use of heroin is in the 21 to 25 year age group (2.0% reported lifetime use) and in the 35-year and older age group (1.8% reported lifetime use). Some areas of the country, such as Boston, have reported dramatic increases in heroin use and overdose in adolescents and young adults associated with increased availability of inexpensive, high-potency heroin that often contains toxic chemical impurities (Kranzler and Ciraulo 56). Among adolescents, heroin use has doubled over the past ten years and has become the second most abused drug next to marijuana (University of Vermont 149).
It is far more common to find misuse of other opioids than heroin abuse. As with heroin, the abuse of nonmedical opioids is predominantly a problem of young adults. The prevalence of nonmedical use of painkillers was reported as 8.6% for lifetime use and 1.2% for use in the past month among persons age 12 years or older. The highest rates were among 18 to 20 years of age and 21 to 25 years of age (15.8% and 13.7%, respectively, reported lifetime use) (Kranzler and Ciraulo 57).
In treating opioid addiction, there are two treatment modalities, psychosocial and pharmacotherapy. The psychosocial approach consists of drug-free behavioral therapy in residential and outpatient settings. Pharmacotherapy relies on the use of agonist, partial agonist, antagonist, and antihypertensive medications to suppress withdrawal symptoms and cravings.
PHARMACOTHERAPY TREATMENT APPROACHES
There are currently three pharmacotherapy treatment approaches that include 1) short-term detoxification, usually with methadone, buprenorphine, or clonidine; 2) opioid substitution therapy, consisting of maintenance treatment with methadone, LAAM, or buprenorphine; 3) antagonist treatment with naltrexone. Detoxification consists of short-term supervised dosing in an inpatient or outpatient setting. Maintenance treatment is a long-term Opiate Substitution Therapy provided in an outpatient setting under a supervised dosing structure.
Methadone Hydrochloride is a synthetic opioid agonist that can suppress withdrawal symptoms up to 24 hours. Since the 1960s, methadone has been the standard pharmacological treatment in the U.S. At present, methadone is the most commonly used drug to treat withdrawal symptoms in detoxification and maintenance treatment.
LAAM (levo-alpha-acetyl-methadol) is a synthetic opioid agonist approved in 1993 by the FDA for the treatment of opiate addiction. Like methadone, LAAM creates a cross-tolerance to other opioids and therefore blocks euphoric effects. Suppression of opiate withdrawal symptoms last 2-3 times longer than with methadone (48-72 hours), therefore dosing can be limited to 3 times per week versus daily clinic dosing visits as with methadone.
Clonidine (Catapress), a nonopioid medication used primarily as an antihypertensive, is another agent now commonly used for detoxification. Since the late 1970s, clonidine repeatedly has shown to suppress some symptoms of the withdrawal syndrome.
Naltrexone (Trexan) and Naloxone (Narcan) are opioid antagonists that bind to the mu-opioid receptor and block the effects of heroin and other opioids. They are non-addictive and do not produce physical dependence or tolerance.
In October 2002, following twenty years of research and clinical trials sponsored by the National Institute on Drug Abuse (NIDA), the FDA approved two sublingual formulations of the Schedule III medication buprenorphine for the treatment of opiate dependence and addiction. Developed through a Cooperative Research and Development Agreement between NIDA and the firm Reckitt Benckiser, Inc., these medications, Subutex (buprenorphine) and Suboxone (buprenorphine/naloxone), are the first and only Schedule III, IV, or V medications to have received such FDA approval and, thus, to be eligible for use under the Drug Abuse Treatment Act of 2000 (DATA), which allows for office-based treatment of opiate addiction. Senator Carl Levin (D-Michigan), coauthor of DATA, said "Approval of this new drug will allow for the long-awaited and appropriate conventional, office-based approach to addiction treatment in this country (Buprenorphine Approval Expands 2).
Buprenorphine was originally developed as an injectable painkiller in the United Kingdom in 1978 under the trade name Temgesic and was soon marketed throughout Europe. In France, it became relatively widely available in 1987 but solely in injectable form. By 1990, its distribution was reduced due to reports of street abuse, and the injectable form was limited to hospital pharmacies. By 1996, it became widely available through unrestricted medical prescription from general practitioners in a sublingually administered form known under the trademark Subutex intended exclusively as a substitute treatment for heroin addiction. By the year 2000, approximately 58,000 addicts were officially on Subutex maintenance compared to only 7,000 on methadone. France was the only European country where buprenorphine was so widely and systematically used in drug treatment (Agar et al. 78). By the year 2004, it was estimated that there was 70,000 patients receiving buprenorphine maintenance treatment in France (Clinical Guidelines 8).
Buprenorphine is an opioid partial agonist at the mu-opioid receptor and an antagonist at the kappa-opioid receptor. This means that, although buprenorphine is an opioid, and thus can produce typical opioid agonist effects and side effects such as euphoria and respiratory depression, its maximal effects are less than those of full agonists like heroin and methadone. At low doses buprenorphine produces sufficient agonist effects lasting up to 72 hours, to enable opioid-addicted individuals to discontinue the misuse of opioids without experiencing withdrawal symptoms.
The agonist effects of buprenorphine increase with increasing doses up to a certain point where the effects plateau and produce the "ceiling effect." Thus, buprenorphine carries a lower risk of abuse, addiction, and side effects compared to full opioid agonists. In fact, in high doses and under certain circumstances, buprenorphine can actually block the effects of full opioid agonists and can precipitate withdrawal symptoms if administered to an opioid-addicted individual while a full agonist is in the bloodstream (Buprenorphine–About 1).
The side effects of buprenorphine are similar to those produced by full opioid agonists and include vomiting, nausea, and constipation. Chronic administration produces opioid dependency characterized by withdrawal upon rapid taper or discontinuation. Intravenous use of buprenorphine can cause significant respiratory depression. There have been deaths reported from the misuse of buprenorphine with other depressants such as benzodiazepines or alcohol (Subutex and Suboxone Approved 14).
Because of its opioid agonist effects, buprenorphine is abusable. In France, buprenorphine without the naloxone agent has been available for years. According to reports from French outreach workers, maintenance patients resell their sublingual prescriptions on the street where they are crushed, dissolved, and injected by street addicts (Agar et al. 79).
SUBUTEX AND SUBOXONE
In the U.S., the two FDA-approved sublingual buprenorphine formulations, Subutex and Suboxone, are under strict treatment protocol designed by SAMHSA and the Center for Substance Abuse Treatment (CSAT). Buprenorphine without the antagonist agent should not reach the streets.
The Subutex formulation is pure buprenorphine. Treatment with Subutex, also known as monotherapy, is generally used in the induction phase of treatment for those dependent on long-acting opioids (methadone and LAAM). Doses are administered at the doctor’s office (under supervision) for 1-2 days after which the patient is prescribed Suboxone on a take-home basis for the stabilization, and detoxification or maintenance phases.
Suboxone is made up of a 4:1 ratio of buprenorphine and naloxone. It is used in all treatment phases for those dependent on short-acting opioids (heroin, Vicodin, Oxycontin). It is the preferred medication for maintenance treatment for all opioids. The naloxone ingredient reduces the likelihood of diversion and abuse. In sublingual form, buprenorphine has moderate bioavailabilty while naloxone has poor bioavailability. This means that the opioid agonist effect of buprenorphine predominates and the antagonist effect of naloxone does not precipitate withdrawal. However, because of naloxone’s good bioavailabilty via the parenteral route, if Suboxone is crushed, dissolved, and injected by an opioid-addicted individual, the antagonist effect will predominate and precipitate withdrawal (About Buprenorphine Therapy 3).
According to a research study lead by Dr. Rolly Johnson of the John Hopkins University in Baltimore, buprenorphine proved as effective as LAAM and high-dose methadone in treating patients addicted to heroin. (Thomas 16).
Buprenorphine is obviously an important alternative to traditional opiate detoxification and maintenance treatment. Its chemical makeup utilizes its potential to suppress withdrawal yet not allow it to be misused.
The pharmacotherapy of the buprenorphine/naloxone (Suboxone) formulation has a built-in safety factor against abuse, diversion, and overdose, a feature not available in methadone or LAAM. Heroin addicts have an unexplainable fear of withdrawal, and for the most part, will avoid using something that will rob them of their "high" and send them straight into their worst nightmare. For this reason alone, I believe addicts seeking Opiate Substitution Therapy for the wrong reasons will avoid buprenorphine. On the other hand, if Subutex (pure buprenorhine) reaches the streets, then we will only repeat the history of abuse in Europe.
Given its three-year history in the U.S., buprenorphine appears to be as effective as methadone and LAAM in treating heroin addicts and painkiller abusers with short-term addictions. Long-term heroin users continue to have better success with methadone and LAAM.
The FDA approval for office-based treatment has an advantage over traditional treatment settings. An individual can obtain a 30-day prescription, for about $10/day, from a local doctor’s office avoiding daily dosing methadone clinics and the negative environment outside their doors and the stigma attached to such clinics.
I started this research paper with the opinion that buprenorphine was just another drug like methadone, that addicts are abusing and substituting for heroin; this is true in Europe. As for the U.S., there were no published reports of abuse at the time of this writing. Give it another couple of years and then revsit the topic. When it comes to figuring out how to abuse a drug, addicts can be very creative. I believe it has major advantages over methadone and if coupled with psychological, emotional, family, and vocational counseling in a residential or outpatient setting with a goal of abstinence, buprenorphine may hold a promising future.
Agar, Bourgorgois, French, Murdoch. “Buprenorphine: “Field Trials” of a New Drug.” Qualitative Health Research Vol. 11 No. 1 Jan 2001 69-84
Bowersoz, Hohn. “Buprenorphine May Soon Be Heroin Treatment Option.” National Institute on Drug Abuse (NIDA) Volume 10 No. 1 10 Oct. 2005
“Buprenorphine – About Buprenorphine Therapy.” Substance Abuse and Mental Health Services Administration, Center for Substance Abuse Treatment 20 Oct. 2005
“Buprenorphine Approval Expands Options for Addiction.” National Institute on Drug Abuse (NIDA) Volume 17 No. 4 11 Nov. 2005
Clinical Guidelines for the Use of Buprenorphine in the Treatment of Opioid Addiction, Treatment Improvement Protocol (TIP) Series 40. Rockville, MD: Department of Health and Human Services, 2004.
Kranzler, M.D. and Ciraulo M.D., Clinical Manual of Addiction Psychopharmacology, Arlington, VA; American Psychiatric Publisings, Inc, 2005.
“Subutex and Suboxone Approved to Treat Opiate Dependence.” U.S. Food and Drug Administration Talk Paper T02-38. 20 Oct. 2005
Thomas, Josephine. “Buprenorphine Proves Effective, Expands Options For Treatment of Heroin Addiction.” National Institute on Drug Abuse (NIDA) Volume 16 No. 2 10 Oct. 2005
“University of Vermount; Medication Appears to be Effective in Treating Teen Heroin Addiction”. Health Insurance Law Weekly 30 Oct. 2005 149. Law Module. Proquest. Saddleback College, Mission Viejo, CA. 11 Nov. 2005
Did you find the addiction treatment information you were looking for? There are more articles and
additional resources on this subject here. Take your time and take a good hard look...