Buprenorphine
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Buprenorphine for the Treatment of Opioid Dependence

Update on buprenorphine for the treatment of opioid dependence


Laura Murphy, RPh, BScPhm, PharmD
Altum Health, University Health Network, Toronto

Pearl Isaac, RPh, BScPhm
Centre for Addiction and Mental Health, Toronto
Leslie Dan Faculty of Pharmacy, University of Toronto

Eva Janecek, RPh, BScPhm
Centre for Addiction and Mental Health, Toronto
Leslie Dan Faculty of Pharmacy, University of Toronto		Anne Kalvik, RPh, BScPhm
Centre for Addiction and Mental Health, Toronto
Leslie Dan Faculty of Pharmacy, University of Toronto

Sarah Woodworth, RPh, BSc(Pharm)
Leslie Dan Faculty of Pharmacy, University of Toronto

Beth Sproule, RPh, BScPhm, PharmD
Centre for Addiction and Mental Health, Toronto


Buprenorphine has been available as a prescription opioid in Canada since 2008. It is marketed as Suboxone® by RB Pharmaceuticals, Canada, in combination with naloxone in a sublingual tablet. This medication has been available for several years in many parts of the world, including the United States. In Canada it is indicated for substitution treatment in opioid drug dependence in adults.

Buprenorphine treatment provides an alternative to methadone maintenance treatment in Canada. As with methadone treatment, patients prescribed buprenorphine should be carefully monitored within a framework of medical, social, and psychosocial support as part of a comprehensive opioid dependence treatment program.1
Pharmacist involvement in buprenorphine treatment can include the supervision of drug administration, monitoring patients, communicating with the treatment team, providing encouragement and support, and dispensing take-home doses (‘carries’).

Involvement in the treatment of opioid dependent patients with buprenorphine has the potential for pharmacists to expand their scope of practice and provide a satisfying professional opportunity to participate in the recovery of individuals dependent on opioids. This area of practice may be of particular interest to those pharmacists involved in the provision of methadone maintenance treatment. Opioid dependence is a complex disorder; therefore pharmacists who take training specific to buprenorphine therapy and other treatment options will be best able to provide pharmacy services to these patients.

With buprenorphine maintenance treatment, as with methadone maintenance treatment, patients benefit from physicians and pharmacists working together effectively to provide optimal treatment.

Recently, clinical practice guidelines were developed by the Centre for Addiction and Mental Health (CAMH) to provide clinical recommendations for the initiation, maintenance and discontinuation of buprenorphine/naloxone maintenance treatment in the ambulatory treatment of adults and adolescents with opioid dependence in Ontario.2

Information in this article has been updated from its first appearance in OCP Pharmacy Connection (Jan-Feb 2008) to reflect these new guidelines. The Guidelines are available from the CAMH, OCP or CPSO websites, and should be reviewed before dispensing buprenorphine.

Key Messages for Buprenorphine
  • Suboxone® is an opioid prescription medication containing buprenorphine 2 mg and 8 mg (in sublingual tablets) in fixed combination with naloxone 0.5 and 2 mg respectively (to deter injection drug use).
  • Sublingual dissolution of Suboxone® sublingual tablets usually takes 2 to 10 minutes.
  • Buprenorphine:
  • is efficacious as substitution therapy in the treatment of opioid dependence.3-5
  • is an alternative to, but not a substitute for, methadone maintenance treatment.6
  • acts primarily as a partial agonist at mu-opioid receptors.1
  • is considered safer in overdose than methadone, although if combined with other CNS depressant drugs (e.g., benzodiazepines) respiratory depression can occur.7 If clinical symptoms of overdose occur, higher doses of naloxone or other measures for treatment may be required.8
  • may have a lower potential for abuse and dependence than pure agonists such as morphine9-10, although abuse does occur.9-11 The addition of naloxone to the Suboxone® product formulation is intended to further reduce the risk of injecting, but does not eliminate the risk.
  • can be titrated to a stable dose within days, in contrast to methadone which typically may take weeks to achieve the optimum dose.
  • prescribed at maximal doses may not be sufficient for all patients. When the maximum daily dose does not stabilize a patient, consideration should be given to using methadone.
  • may induce withdrawal in patients dependent on opioids if administered too soon after last use of full opioid agonist.
  • has also been successfully used for medical withdrawal treatment (detoxification) from opioids7,12 and for the treatment of pain13 (both are unapproved indications in Canada).
Regulatory Framework for Buprenorphine

Buprenorphine/naloxone does not require a special prescribing exemption, unlike methadone, so prescriptions may be written by any practitioner licensed to prescribe narcotics. The College of Physicians and Surgeons of Ontario (CPSO) expects all physicians who wish to use buprenorphine to treat opioid-dependent patients to have training/education on this drug, and addiction medicine generally, prior to initiating buprenorphine treatment.
Prescriptions for Suboxone® have the same requirements as other "straight narcotics", however, in addition it would be good practice to also indicate:
  • start and stop dates
  • days for supervised administration
  • days for take home doses
As with other opioids, dispensing procedures for buprenorphine/naloxone must comply with the Narcotics Safety and Awareness Act, 2010, as part of Ontario’s Narcotic Strategy for monitored drugs.14
The new Guidelines highly recommend that pharmacists who provide buprenorphine services undertake training. These pharmacists must be aware of the unique nature of buprenorphine dispensing and specific issues that exist in dispensing medications for the maintenance treatment of substance dependence. Training resources are included at the end of the article.

How Buprenorphine Works

Buprenorphine is a synthetic opioid with a unique profile: it is a partial mu-opioid receptor agonist.1 Buprenorphine has a lower intrinsic activity at the mu-opioid receptor than a full agonist (e.g., methadone or oxycodone). This means that there is a “ceiling effect” to its opioid agonist effects at higher doses15 making it safer in overdose and reducing its potential for abuse. In addition, there is little increase in efficacy with doses above 16-32 mg daily. Although it is a partial agonist, buprenorphine has a very high affinity for (i.e., binds tightly to) the mu receptor. This tight binding means that buprenorphine can block the effects of other opioid agonists (e.g., methadone or oxycodone), and precipitate withdrawal in those physically dependent on opioids by displacing agonists from opioid receptors.1 The tight binding is also associated with a slow dissociation from the mu receptor resulting in a long duration of action.1 This is why buprenorphine is associated with a milder withdrawal syndrome and has been used to assist in detoxification from other opioids.7,12
Buprenorphine’s partial mu-opioid agonist activity is beneficial in the treatment of opioid dependence because:
  • It reduces craving for opioids.
  • It may block the effects of other opioids (e.g., morphine, oxycodone, heroin).
  • It can attenuate opioid withdrawal.
Pharmacokinetic Characteristics Specific to Buprenorphine16

Buprenorphine’s pharmacokinetic properties allow it to be utilized as a feasible substitution treatment for opioid dependence. Buprenorphine has poor oral bioavailability due to extensive metabolism by intestine and liver. Sublingual administration allows absorption through the oral mucosa and thus prevents breakdown via first-pass metabolism. Suboxone® tablets are formulated to be dissolved under the tongue. The onset of action is slow with peak effects from sublingual administration occurring 3-4 hours after dosing. Buprenorphine is converted in the liver primarily by cytochrome P450 (CYP) 3A4 to an active metabolite (norbuprenorphine) with weak intrinsic activity. Both norbuprenorphine and buprenorphine are subject to hepatic glucuronidation. The mean elimination half-life is indicated as 37 hours in the product monograph2, with evidence in the literature of large inter-individual variation (24 to 69 hours) following sublingual administration.16 Most of the dose is eliminated in the feces, with approximately 10–30% excreted in urine.
The slow onset of action and extended duration of action are both desired features in a treatment for opioid dependence. It is possible that buprenorphine can be given on an alternate day or three times weekly dosing schedule once the patient has been stabilized on a daily buprenophine dose.

Notes about naloxone:
Naloxone, a pure opioid antagonist, is contained in Suboxone® tablets in combination with buprenorphine, with the intention of deterring patients from dissolving and injecting the tablet. When injected, naloxone may attenuate the effects of buprenorphine or cause opioid withdrawal effects in opioid-dependent individuals. However, the effect may be limited by the short half-life of naloxone and the relatively stronger binding by buprenorphine to the receptors.
When Suboxone® is used sublingually, naloxone is largely unabsorbed and does not exert pharmacological activity.16
Naloxone in Suboxone® tablets does not appear to influence the pharmacokinetics of buprenorphine.16

Clinical Assessment Considerations

Clinical considerations for the use of buprenorphine must include a distinction between a diagnosis of “opioid dependence” and “physical dependence”. “Opioid dependence” can be considered the same as “addiction” which is characterized by a loss of control over opioid use, continued use despite knowledge of harmful consequences, compulsion to use and/or cravings. “Physical dependence” to opioids refers to the physiological adaptations that occur with regular exposure to opioids, which result in the development of tolerance and the appearance of withdrawal symptoms when the opioid dose is lowered or stopped. Many patients on chronic opioid therapy become physically dependent but not addicted. Physical dependence alone does not indicate a diagnosis of opioid dependence.
Contraindications to buprenorphine/ naloxone are:
  • Allergy to buprenorphine/naloxone
  • Severe liver dysfunction
  • Acute severe respiratory distress
  • Paralytic ileus
  • Decreased level of consciousness
  • Inability to provide informed consent
Dosing Information

The product monograph states that Suboxone® must be given daily with supervised dosing by a health professional (e.g. a pharmacist) for a minimum of 2 months.1 The exception to this is in circumstances in which the pharmacy is not open on weekends, in which case suitable patients may receive take-home doses for Saturday and/or Sunday.1 In the CAMH Guidelines, this is further qualified by stating that additional take-home doses earlier than two months could be provided if the physician decides that a patient would benefit from this and that the patient has a degree of clinical stability that would make them eligible for take-home doses. The patient must be made aware that this is against the Health Canada label, as well as all of the possible additional risks of receiving take-home dosing early in treatment such as overdose, careless storage and unintended ingestion by others, injection and diversion. Physicians must document their rationale for the early take-home doses and their discussion with the patient about the risks. Take-home doses should be increased gradually and the patient carefully monitored. Refer to the Guidelines for further information.

Induction

Therapy is initiated when the patient is experiencing opioid withdrawal symptoms:
  • at least 6-12 hours (preferably 12 hours) after use of short-acting opioid (e.g., heroin, oxycodone)2, or
  • at least 12-24 hours (preferably 24 hours) or longer after the use of a long-acting opioid (e.g., OxyContin® when swallowed whole).
  • For methadone maintenance patients wanting to switch to Suboxone®, waiting 3-5 days after the last dose of methadone before starting buprenorphine/naloxone is recommended. The methadone dose should be tapered down to 30 mg or less before buprenorphine treatment is initiated to minimize the possible precipitation of intense withdrawal symptoms.
  • At least 48 hours may be needed for patients discontinuing fentanyl patch use.
  • Initially a single dose of 2 to 4mg is given under supervision. An additional 4 mg may be administered later on in the same day depending on the individual patient’s requirement.
Initial doses may be:
  • prescribed by physician, dispensed and dosing observed by pharmacist, or
  • prescribed by physician, dispensed by pharmacist, dosing observed in physician’s office, or
  • prescribed, dispensed and observed in the physician’s office.
Case: Mr. M
Mr. M arrives at the pharmacy Tuesday morning for his first scheduled dose of Suboxone®4mg. He has recently stopped his chronic opioid therapy and reports that his last dose of OxyContin® was approximately 12 hours prior. The pharmacist confirms that he is showing/experiencing signs of opioid withdrawal, including mild headache and some mild nausea. The pharmacist observes Mr. M take his Suboxone® 4mg sublingual dose as prescribed and ensures that the SL tablet has dissolved completely. The pharmacist dispenses two additional Suboxone® 2mg tablets, as prescribed, for Mr. M to take home in case his withdrawal symptoms re-appear in the evening. Approximately 45 minutes later that same day, Mr. M returns to the pharmacy and reports worsening symptoms including sweating, increase in his headache, runny nose, abdominal upset with increased nausea, as well as diarrhea.
Due to the timeframe of Mr. M`s worsened symptoms of withdrawal, the pharmacist counsels Mr. M that is likely experiencing symptoms of precipitated opioid withdrawal from his first dose of buprenorphine. Mr. M admits that he actually had his last dose this morning, since was worried about how long he would have to wait for his Suboxone® dose to ``kick in``.
Mr. M asks the pharmacist if he should take the additional 2mg dose now, to help with his worsened symptoms of withdrawal?

Precipitation of opioid withdrawal symptoms may occur when the patient is initiated on buprenorphine/naloxone if they are not yet in satisfactory opioid withdrawal. In these situations, buprenorphine, the high affinity partial mu agonist, displaces the full mu agonist opioid from the mu receptors triggering a decrease in receptor activity and lead to a worsening of opioid withdrawal symptoms. If buprenorphine is taken when a patient is in sufficient opioid withdrawal, the partial agonism will cause relief of the withdrawal symptoms. Consideration should be given to reassessing the patient one hour after the first dose of buprenorphine to assess for possible precipitated withdrawal. Additional doses of Suboxone are not recommended for precipitated withdrawal, rather, symptomatic management of withdrawal symptoms is preferred. The prescriber should be notified of the situation and Suboxone® induction rescheduled, typically for the next day. Abstinence from other opioids should be encouraged during this time.

Maintenance

The dose should be increased progressively according to the individual patient’s needs and should not exceed a maximum daily dose of 24 mg according to the product monograph.1 Average maintenance doses have generally been found to be 8-12mg per day.2 The dose is titrated according to reassessment of the physical and psychological status of the patient.1 Stable doses of Suboxone® can be reached in a few days.
Once a patient has been stabilized on a maintenance dose, there is the option to reduce the frequency of administration for suitable patients (e.g., if doses have not been missed or when an alternative to take-home doses is needed for work or travel).17 Alternate day doses are given at double the daily dose (e.g., 16 mg q2days for a patient maintained on 8 mg per day). An example of three times weekly administration for a patient maintained on 8 mg per day would be: Monday and Wednesday doses given at twice the daily dose (i.e., 16 mg) and a Friday dose at 3 times the daily dose (i.e., 24 mg). The dose given on any given day should not exceed 24 mg.

Observed Dosing

Case: Mr. Y
Mr. Y is a 54 year-old male with a history of opioid dependence, who is maintained on buprenorphine/naloxone (Suboxone®). He has a history of opioid-taking behaviours that are associated with an increased risk of overdose, including taking more opioid analgesics than prescribed when he was using OxyContin®, and stock-piling his previously prescribed methadone carries.
According to his pharmacy records his buprenorphine had been prescribed as 8 mg SL on Monday, Wednesdays, and 12mg on Fridays. During a visit with his physician 4 weeks after starting,Suboxone®, Mr. Y reports he is actually taking 1/2 of an 8mg tablet every day. He stated that his pharmacy permits him to take 1/2 of the tablet home for the days he does not have observed dosing.
During a discussion with the physician, the pharmacist reported that they had not given permission for him to take 1/2 of the observed dose home, but that it takes a very long time to observe Mr Y taking the whole dose, and that it was possible he took the initiative to take a split portion of the dose home.

Water can be provided to patients before their dose to moisten the mouth and potentially decrease the time it takes for the tablet to dissolve. The 8 mg tablets, although not scored, may be split to speed up dissolution, but all pieces should be placed in the mouth to dissolve at the same time. Observed dosing includes checking under the tongue to ensure dissolution of the SL tablet in order to decrease the risk of diversion. A pharmacist can provide take-home doses or portions of doses only if it is indicated on the prescription.

Supervised dosing by pharmacists ensures patient adherence with buprenorphine therapy and that medications are being taken appropriately, which may help achieve positive outcomes for patients in opioid dependence treatment programs, and especially those with a history of aberrant medication-related behaviours outlined in this case. Observed dose dispensing services are part of a structured opioid treatment program and can act as an effective mechanism to stabilize patients.

Recommended dispensing procedure for pharmacists:
  • Confirm identify of patients using photo identification, especially when the patient is not known to the pharmacist.
  • Assess patients for intoxication and compliance prior to dosing.
  • Dosing is best done in a private area of the pharmacy where the patient can sit undisturbed by other patients, yet still be observed by the pharmacist.
  • Push tablets through foil wrapping into medication cup to minimize handling.
  • If the Suboxone® dose consists of more than one tablet, all tablets can be placed under the tongue together.
  • Dissolution of Suboxone® tablets is not immediate and may require up to 10 minutes to completely dissolve under the tongue. After 1-3 minutes, pharmacists should check under the tongue to assess for dissolution, this is the most important time for reducing the possibility of dose diversion, e.g. once the tablet begins to dissolve it becomes more difficult to divert. Pharmacists should keep in mind that a chalky residue may remain after the drug has been absorbed.
  • Drinking water or other fluids immediately prior to taking Suboxone® may moisten the mouth and enhance dissolution of tablets and speed up the dosing administration process.
  • Patients should be instructed not to swallow their saliva or suck on the tablets while the tablets are dissolving.
  • Patients should refrain from drinking fluids or eating for approximately 5 minutes after tablets have dissolved in order to ensure that the full dose of medication has been absorbed.
  • If the patient vomits after taking the dose, there is no effect on buprenorphine absorption once the tablet has dissolved.
  • Finally, pharmacists should consider using a treatment agreement with the patient in order to communicate information regarding practical issues pertaining to pharmacy routine and services, as well as expectations of the patient and pharmacy staff. A sample treatment agreement is available in the CAMH Guidelines Supplement 5: Buprenorphine/Naloxone Dispensing.2
Take-home doses

Take-home dosing can be considered based on the assessment of clinical stability, length of time in treatment and the patient’s ability to safely store the drug. The decision regarding take-home doses should involve collaboration between the patient, pharmacist and physician. Patients with take home doses should be assessed and reviewed on regular basis. (See also the dosing information section above.)
Pharmacists may consider having an initial pharmacy/patient treatment agreement that would include information on safety issues with patients starting to take doses home.

Take home doses should be kept in the original strip packaging. Use of childproof closures are recommended. Take home doses need to be securely stored.

Management of Missed Doses

Compliance with buprenorphine treatment needs to be monitored by the pharmacist. Any missed doses should be communicated to the prescriber. The pharmacist should consult the prescriber to develop a plan on how to continue with buprenorphine treatment after more than 5 missed consecutive doses. Recommendations for new starting doses are available in the CAMH Guidelines2 based on the patient’s buprenorphine dose and number of consecutive doses missed.

Management of Intoxicated Patients

Case: Ms. P.
It is Friday evening and Ms. P arrives at the pharmacy for her observed daily dose of buprenorphine/naloxone. She has been maintained on Suboxone® 24 mg daily for the past 3 months. When the pharmacist greets her at the counter, she is wearing sunglasses and stumbling as she walks. After further assessment, the pharmacist notices that her eyes are reddened, she is slurring her words, and is slightly confused. With further questioning, the pharmacist confirms that Ms. P is intoxicated with alcohol. She received her last dose of Suboxone® on the previous day.
Ms. P asks the pharmacist if she can return later in the day to receive her observed dose of Suboxone®.

Prior to dosing administration, dispensing pharmacists should assess patients for possible intoxication. For purposes of patient safety, patients should not receive a dose of buprenorphine/naloxone if they appear intoxicated or sedated. In some cases, pharmacists will need to decide to hold or delay administration. It is recommended that the prescribing physician be contacted to make a collaborative decision on patient management. Patient safety is paramount. Due to the long duration of action of buprenorphine/naloxone, it is reasonable to hold one day’s dose and reassess the next day. Education should be provided to the patient to reinforce safety risks of buprenorphine/naloxone, especially when used in combination with alcohol (or sedatives).

To help prevent such a situation, it is recommended that pharmacists communicate with patients at initiation of Suboxone® treatment and on an ongoing basis to discuss a protocol for management if patients present to the pharmacy for their observed Suboxone® dose while intoxicated. Pharmacists should be familiar with signs and symptoms of intoxication in order to enable them to recognize and make a judgement on the degree of intoxication.

Continuity of Care

Communication must occur among pharmacists and other health care providers (as with methadone maintenance treatment) to ensure that there are no omissions or overlaps in buprenorphine dosing. This is important when a patient is switching pharmacies, or is admitted or discharged from institutions such as hospitals or jails.

Unapproved Uses For Suboxone

Withdrawal Treatment
Although not officially approved for opioid detoxification, buprenorphine treatment has been shown to be well accepted by patients and effective for use in detoxification from opioids.18,19 Buprenophine has also been used to assist those in the final stage of withdrawal from methadone. In this case the dose of methadone should be tapered down to 30 mg or less before treatment is switched in order to avoid precipitating withdrawal.

Pain Treatment
Buprenorphine has been prescribed in the context of treatment of pain and chemical dependence.13

Adverse Effects

It is important to distinguish adverse effects from withdrawal symptoms that can be precipitated by buprenorphine.
As discussed above, after the first dose of buprenorphine there may be some precipitated opioid withdrawal symptoms, such as headache, gastrointestinal upset, nausea, diarrhea, runny nose, sweating.
Adverse effects during buprenorphine treatment are dose related and similar to other opioids. Most common are constipation, headache, CNS depression (e.g, sedation) euphoria, sweating, nausea, insomnia and orthostatic hypotension.

Toxic effects can be caused by buprenorphine alone or in combination with other CNS depressants.
Since buprenorphine is a partial agonist, there is a ceiling effect on respiratory depression, however, very high doses of buprenophine in some individuals have been associated with severe symptoms. Respiratory depression, when it occurs, may be delayed in onset and more prolonged than with opioids such as morphine, and reversal with naloxone is more difficult due to buprenorphine’s very tight binding to opioid receptors. Other treatment approaches may be necessary (e.g., assisted ventilation).

Drug Interactions
Serious respiratory depression has occurred when buprenorphine has been combined with CNS depressants including other opioids, alcohol, benzodiazepines, certain antidepressants, sedating H1-receptor antagonists, barbiturates.1
Special caution is recommended with the use of benzodiazepines and buprenorphine as this combination has resulted in respiratory depression, coma and death.1
Medications with CNS effects should be avoided and patients counselled regarding the risks associated with alcohol and benzodiazepine use.1

Buprenorphine is primarily metabolized by CYP3A4. Inducers (e.g., phenytoin, carbamazepine, rifampin) or inhibitors (e.g., ketoconazole, fluvoxamine, erythromycin, indinavir, saquinavir) of this enzyme would be expected to interact with buprenorphine. Ketoconazole, a powerful inhibitor of CYP3A4, has received particular attention and it has been reported to significantly increase peak plasma concentrations of buprenorphine.16 Careful patient monitoring and adjustment of buprenorphine dose when necessary, is recommended.

Special Patient Populations:

Pregnant Patients
The role of buprenorphine in pregnancy has not been clearly elucidated and Suboxone® is not approved for use in this population.1

Studies have shown that buprenorphine is efficacious, well tolerated and safe in pregnancy.20, 21 Neonatal withdrawal can occur, although some sources indicate that symptoms are mild or absent in many cases.7;22 Although buprenorphine may prove to be a suitable option for the treatment of opioid dependence during pregnancy, the role and safety of naloxone in this setting is not known. Buprenorphine without naloxone may be an option for some patients through Health Canada’s Special Access Programme. The current standard of care for the treatment of opioid dependence in pregnancy is methadone treatment.

Patients with Renal or Hepatic Failure
The dose of buprenorphine does not have to be significantly adjusted in renal impairment.16 It is possible that the dose may need to be modified in chronic liver disease.16

Abuse of Buprenorphine

Buprenorphine is considered to have a lower potential for abuse due to its pharmacological properties (i.e., partial opioid agonist activity) compared to opioids which are full agonists, e.g oxycodone or morphine. However, abuse has been reported in countries where both buprenorphine alone and in combination with naloxone are available.9-11

Buprenorphine has been abused by crushing and then administration by snorting or by the intravenous route.
Supervised daily dosing in the first 2 months of buprenorphine treatment is intended to reduce the risk of diversion. Pharmacists may minimize diversion through careful dispensing and dose monitoring, watching for “double doctoring” and communicating possible diversion (e.g., lost or stolen carries) to the physician.

Use of diverted buprenorphine by opioid-naïve people can result in overdose, particularly when combined with alcohol, benzodiazepines or other CNS depressants. Diversion for use in a person dependent on methadone or other opioids can cause them to experience precipitated withdrawal.



Conclusion

Buprenorphine is available as Suboxone®, approved for the treatment of opioid dependence. This sublingual formulation is combined with naloxone to deter intravenous use. Pharmacists in Ontario have an opportunity play an important role in the management of Suboxone® treatment with other members of the treatment team.

Opioid substitution therapy, whether with buprenorphine or methadone, has been shown to be far more effective than detoxification in improving health and drug outcomes in the treatment of opioid dependence.22 Buprenorphine has several advantages when compared to methadone: it is safer in overdose, optimal dosing can be achieved quickly, it may be associated with less abuse and diversion, it may be easier to taper, it may be associated with less stigma and may be more convenient for the patient. New clinical practice guidelines are available from CAMH on the use of buprenorphine/naloxone for opioid dependence. They provide evidence-based clinical recommendations developed by a multidisciplinary committee, and are available from the CAMH, OCP or CPSO websites.2

Buprenorphine may be considered a first line therapy, especially in those with a shorter history of opioid dependence and lower levels of opioid agonist needs. However, those that do not do well on maximum doses of Suboxone® (24mg daily) may need to switch to methadone with its greater dosage range.

There is growing evidence that the problem of prescription opioid abuse is increasing in Ontario.25 The number of individuals seeking detoxification treatment from OxyContin® at CAMH increased significantly from 2000-200426 and there has been an 80% increase in the demand for addiction treatment for prescription opioid dependence over the last five years in Ontario.27 The College of Physicians and Surgeon's of Ontario released a document in August 2010 entitled "Avoiding Abuse, Achieving a Balance: Tackling the Opioid Public Health Crisis". Pharmacists are vital health-care team members, central to the increasing problem of prescription opioid abuse and addiction. The profession needs to take a lead role and actively engage in being part of the solution to this problem.28 The Canadian Guideline for Safe and Effective Use of Opioids for Chronic Non-Cancer Pain (http://nationalpaincentre.mcmaster.ca/opioid/) provides guidance for pharmacists in managing patients on chronic opioid therapy. Developing expertise in the pharmacological treatment of opioid dependence is also an important component of this engagement.

Involvement in buprenorphine treatment provides pharmacists with increased opportunities to provide pharmaceutical care to patients with opioid dependence. Pharmacists who already provide methadone services may be in a position to expand their scope of practice and further participate in the recovery of their patients with opioid dependence. Pharmacists in most cases see the patient more frequently than the prescribing physician. This means that direct open communication between the physician and pharmacist is essential for the optimal care of patients receiving Suboxone® treatment. Possible barriers for patients to access treatment include the cost of Suboxone®. Another challenge is the ability to provide a suitable, confidential area in the pharmacy where patients can wait while the Suboxone® dose is dissolving under the observation of the pharmacist.

Pharmacists who take buprenorphine training are best able to provide support and encouragement and to help prevent, identify and resolve drug-related problems in their patients on Suboxone® treatment. Good communication between the pharmacist, physician and patient will result in optimal patient care before, during and throughout Suboxone® treatment.

Buprenorphine Training Resources

The CAMH Opioid Dependence Treatment Core Course now includes training on both methadone and buprenorphine. (www.camh.net/education/l)
The CAMH manual “Methadone Maintenance: A Pharmacist’s Guide to Treatment” is currently being updated and the new edition will include buprenorphine maintenance treatment. It should be available later this year.
While waiting to take full training, pharmacists can access the Reckitt-Benckiser online Suboxone Education Program at www.suboxonecme.ca.


Reference List
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13. Heit H, Gourlay DL. Buprenorphine. New Tricks With an Old Molecule for Pain Management. Clin J Pain 2008;24:93–97.
14. Ontario’s Narcotic Strategy, MOHLTC: http://www.health.gov.on.ca/en/pro/programs/drugs/ons/about.aspx
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