Mental health & crisis management 7 APRIL qui z

Opioids and Clinical Opiate Withdrawal Score (COWS)

Box 18-2 Canada's Fentanyl Public Health Crisis

Developed in 1959 for use as a general anesthetic, fentanyl is therapeutically used to provide physical and emotional relief from acute pain, principally for palliative care patients or those with long-term chronic pain who experience breakthrough pain when using other less potent opioids. It has rapid onset and short duration of action; thus it is primarily administered transdermally in a hospital setting to make its use more convenient for those who are severely ill, with each patch designed to slowly release the potent substance over 72 hours.

In 2017, illicit street use of the potent licit synthetic opioid fentanyl became a national public health crisis, with overdose deaths in Canada reaching new levels. A decade before, a less potent licit synthetic opioid oxycontin had likewise become a public health issue, which led to its use being prohibited but without the development of a concurrent treatment strategy for those who had become addicted. In fact, during this time the Harper government appealed all the way to the Supreme Court of Canada in an attempt to shutter the nation's lone supervised injection site; after losing that appeal, the government introduced legislation creating additional barriers to opening any new facility anywhere in Canada.

Historically, whenever a psychoactive substance is prohibited, in its void an alternative arises (Csiernik, 2016). Unfortunately in this case the prohibition of oxycontin, which was accompanied by its manufacturer, Purdue Pharma, paying a $600 million fine for product misbranding, led to an increase in heroin use. However, heroin is both expensive and illicit, whereas fentanyl, a synthetic drug that is 3 times as potent as uncut heroin and 100 times as potent as morphine, is both far cheaper to manufacture and can be legally produced in nations such as China. Across Canada, the cheaper fentanyl was being mixed with heroin, and at times cocaine, so that less of the expensive drug needed to be used and thus drug dealers could increase their profit margins. Combining the two drugs in street-level labs, however, often creates “hot spots” where more fentanyl is incorporated into the mix and thus the risk of overdose is further increased. Along with fentanyl, another synthetic opioid, even more potent, carfentanil began to be used for this purpose, again increasing the likelihood of each injection leading to an overdose.

 

Canada is facing a national opioid crisis. The growing number of overdoses and deaths caused by opioids, including fentanyl, is a public health crisis. This is a complex health and social issue that needs a response that is comprehensive, collaborative, compassionate and evidence-based.

 

Since January 2016 there have been:

· 15,393 Apparent opioid-related deaths, or 11 per day

· 19,377 Opioid-related poisoning hospitalizations, or 13 per day

 

While lower numbers of opioid-related harms have been noted in 2019 compared to 2018, trend analysis indicate no significant decrease and rates have remained high.

 

Rate of opioid-related harms per 100,000 population

Harm	2016	2017	2018	2019
Apparent opioid-related deaths	8.6	11.3	11.9	10.2
Opioid-related poisoning hospitalizations	16.8	18.4	17.6	15.2

 

According to available opioid-related poisoning hospitalization data in 2019:

· 4,435 opioid-related poisoning hospitalizations occurred between January and December of which 62% were accidental;

 

Among accidental opioid-related poisoning hospitalizations:

· 3 in 5 were male;

· 49% were among young and middle aged adults (20-49 years);

· 46% were among older adults (≥ 50 years);

· 25% involved fentanyl or fentanyl analogues;

· 28% involved one or more types of non-opioid substances;

 

According to available Emergency Medical Services (EMS) data in 2019:

· More than 21,000 EMS responses for suspected opioid overdoses occurred between January and September;

 

Based on available data from 9 provinces and territories;

· 3 in 4 were male;

· 75% were among young and middle aged adults (20-49 years);

· 22% were among older adults (≥ 50 years);

 

 

What is the Government of Canada doing about the opioid crisis?

Under the Joint Statement of Action to Address the Opioid Crisis, Health Canada committed to take new action across the Health Portfolio.

 

The Health Portfolio’s actions to address the opioid crisis complement the Government of Canada’s overall approach to drug policy, which is:

· collaborative

· compassionate

· comprehensive

· evidence-based

 

These values are reflected in our Canadian drugs and substances strategy. Led by the Minister of Health, this strategy is a balanced and health-focused approach to drug policy, involving:

· a strong foundation in evidence

· the restoration of harm reduction

· prevention

· treatment

· enforcement

 

The Government of Canada is committed to taking action on Canada’s opioid crisis through a targeted public health response and through:

· Prevention

· Treatment

· Harm reduction

· Enforcement

 

Actions in these areas will be supported by a strong evidence base.

 

Opioid withdrawal

As with alcohol, a protocol has been established to assist with opioid withdrawal. The Clinical Opiate Withdrawal Scale (COWS) was developed for buprenorphine/naloxone induction, though it can also be used in a variety of clinical settings such as assessing acute opioid withdrawal during an opioid detoxification, methadone maintenance, or methadone treatment, as well as during the treatment of chronic pain

Pharmacological Treatment of Opioid Addiction

Methadone (Metadol) is a synthetic opioid that blocks the craving for and effects of opioids. It has to be taken every day, produces high physical and psychological dependency, and, when stopped, produces withdrawal symptoms that those in withdrawal have equated to the pain of bone cancer at its peak. Therefore for methadone to be effective, the patient must take a dose at a prescribed level that will prevent withdrawal symptoms, block drug craving, and block any effects of illicit use of short-acting opioids.

Methadone inhibits ascending pain pathways and alters the perception of and response to pain, and although it has morphine-like actions and cross-tolerance, it does not produce euphoria for opioid users when given orally. This has led to its current primary use in substitution therapy for opioid-dependent individuals. However, tolerance and withdrawal do readily occur in methadone users, though their development is much slower than with other opioids. Methadone's side effects include weight gain, constipation, numbness in the extremities, and, for some, hallucinations when they first begin to use the substance.

Buprenorphine is a partial µ-opioid receptor agonist and, in combination with the opioid antagonist naloxone in a 4 : 1 ratio, is used as an alternative to methadone in opioid drug substitution. When this combination drug known as Suboxone is taken sublingually, it takes from 2 to 10 minutes to dissolve. Used in this manner, the naloxone exerts no clinically significant effect, leaving only the opioid agonist effects of buprenorphine. However, if a patient attempts to inject Suboxone, the opioid antagonism of naloxone causes the user to go into withdrawal. This nearly immediate physical response greatly reduces the abuse potential of the compound drug. Suboxone users report more clarity of thinking, greater confidence, and lower stigma compared to those using methadone. However, Suboxone, like methadone, produces physical dependency and, as with all opioid substances, can slow and even stop respiration, though it is less likely than methadone to produce an overdose ( Orman & Keating, 2009 ;  Tanner, Bordon, Conroy, et al., 2011 ).

Naltrexone (ReVia) was originally developed as an opioid antagonist, and as a relatively pure antagonist, it blocks the euphoric effects of opioids well. It has low toxicity and few adverse effects and does not produce dependence, as it is not a psychoactive substance itself. A single dose provides an effective opioid blockade for up to 72 hours. Taking naltrexone three times a week is sufficient to maintain a fairly high level of opioid blockade. For many patients, long-term use results in gradual extinction of cravings.

Clonidine (Catapres) was initially marketed for high blood pressure, but it was also found to be an effective somatic treatment, combined with naltrexone, for some chemical-dependent individuals. Clonidine is a nonopioid suppresser of opioid withdrawal symptoms and as such does not produce physical dependency when used regularly. A Cochrane review found clonidine to be more effective than placebo for the management of withdrawal from heroin or methadone, though methadone is associated with fewer adverse effects than clonidine (Gowing, Farrell, Ali, et al., 2014).