Addiction is a long term condition with high rates of mortality and morbidity. Prevalence of opioid-associated problems including addiction is reported to be increasing in Australia and chances are high for medical practitioners to come in contact with the drug abuse patients. Opioid substitution treatment is solution for this crisis and there is enough substantial evidences to back up this statement. If implemented effectively, it will benefit individual patients and in long run, public health if adopted by greater number of medical practitioners.
Opioid substitution treatment is most effective when it is used as a part of patient’s rehabilitation program. One should exercise caution while prescribing such treatment as it is not suitable for everyone. Common drugs in use are methadone, naltrexone and buprenorphine with or without naloxone. Regular monitoring is important to ensure the efficacy and safety of the treatment. It also aids in preventing patients from dropping out and relapsing.
Relevant drug abuse history is mostly provided by the care givers, family members, friends or EMS providers. Possession of pill bottles, drug supplies or eyewitness accounts also aids in diagnosis. Administration of a trial dose of naloxone by EMS is often helpful in confirming the diagnosis. Important aspects that have to be taken into consideration for ascertaining drug abuse include ingestion time, quantity and identification of co-ingestants.
Abuse and dependence
Urine drug testing (UDT) is a routine test conducted to check for the presence of drugs in suspected cases. The UDT result can be obtained in 1-4 days. Sweat and hair samples are also used for the test in some cases. Blood alcohol levels are also checked.
Complete blood count test and analysis of electrolytic imbalances are routinely performed. Urine drug screen is not recommended
Half-life, bio transformation and excretory path of the drug are vitals factors in accurate drug abuse detection. Comprehensive UDT is performed in suspected drug abuse cases. Thin-layer chromatography (TLC) though inexpensive is not recommended owning to its failure to detect commonly abused drugs including fentanyl. Though more sensitive than TLC, enzyme immunoassay and radioimmunoassay are also less specific as the molecules with similar functional groups cross-react with antibodies. Gas-liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS) are very sensitive and specific in diagnosis but have major drawbacks. Running tests for diagnosis are time consuming, labor intensive, and expensive.
IV drug abuse are always associated with additional risks of contracting blood borne infections and in such case the following tests are recommended to rule out the possibility of such infections.
Assessment of physical dependence
Manifestation of withdrawal symptoms lasting for 30-60 minutes after an intramuscular injection or IV of naloxone of (0.2-0.8 mg) proves physical dependence. This procedure is highly recommended especially before starting of opiate antagonist maintenance therapy after detoxification as the development of withdrawal symptoms persuade patients to discontinue the treatment.
As per federal governments regulations, the drug testing results are submitted directly to medical review offices to avoid misdiagnosis.
Medical interventions are necessary to treat acute cases of opioid intoxication, overdose, and withdrawal. Treatment strategies followed in chronic opioid abuse include opioid agonist therapy (OAT), psychotherapy, and pain management in patients undergoing maintenance therapy.
General supportive measures upon admission for opioid intoxication is as follows
Naloxone is the drug of choice for first-line treatment of opioid overdose. At home naloxone treatment is initiated in many countries and is met with success. Implementation of such programs should be throughly supervised to prevent further complication due to lack of immediate medical care and ineffective management of associated side effects.
Community-based programs offered naloxone and other opioid overdose prevention services to over 53,000 caregivers and patients who abuse drugs in 1996. FDA has approved the use of naloxone (Evzio) autoinjector which delivers 0.4 mg dosage (as IM or SC in the anterolateral aspect of the thigh) to treat opioid overdose at home. The device is equipped with an audio and video instructions and it also instruct users to undergo emergency medical care directly after use   .
Opioid maintenance therapy
Improvement and management of withdrawal symptoms is central in case of opioid maintenance therapy. This is achieved by using legally procured opioid agonists in place of heroin or other opioids. This strategy will help in successful management for many risk factors associated with drug-abusing lifestyle.
Methadone maintenance therapy (MMT)
The need for multiple daily heroin doses can be effectively replaced with MMT. Methadone is a synthetic opioid agonist which requires only a single dose a day to remain effective. It is mainly used to counterbalance the drug-abusing lifestyle of the victims and help in reducing criminal behaviors and needle sharing practice thereby decreasing the risk of contracting HIV and other blood borne diseases. MMT has been a standerd treatment option for opioid maintenance therapy for more than 30 years.
Methadone is a highly regulated Schedule II medication, which is available only at specialized methadone maintenance clinics. It can house only 15-20% of US heroin addicts and often create controversy in populace fearful of addicts in different recovery phases. In addition to that effectiveness of methadone clinics is under question owing to several reasons including inability of patients to present themselves in clinics and due to the fear of stigmatization associated with it.
Buprenorphine maintenance therapy (BMT)
Recent introduction of BMT has resulted in commendable improvements in the medical management of opioid-dependent patients. Buprenorphine (mu-opioid partial agonist), like methadone has similar mode of action and is effective in containing the withdrawal symptoms. Advantages of BMT over MMT is that it has a wider margin of safety in case of accidental overdose. This is termed as "ceiling effect" as buprenorphine becomes ineffective at higher doses. Owning to its safe nature it is available by prescription as a Schedule III medication. One major concern regarding the use of buprenorphin is the possible oral or intravenous drug abuse. Combination of buprenorphine with naloxone in a 4:1 ratio (Suboxone, Zubsolv) or a 6-7:1 ratio (Bunavail) is used to circumvent this issue. Naloxone is not effective when administered orally and when consumed intravenously it will lead to withdrawal symptoms thereby discouraging the patients from misusing it.
Limitation of BMT
Only certified physicians who meet the criteria outlined in the Drug Abuse Treatment Act of 2000 are allowed to follow BMT. An 8-hour certificate course on this subject will permit clinicians to include buprenorphine in their treatment. The upper limit of patients under buprenorphine is 30 per physician but this limit will soon be increased . The efficacy of BMT over existing treatment was proved in a recent study by Ling et al on patients using buprenorphine implants to overcome opioid dependence. The study proved that the physiological and psychological difficulties associated with maintenance therapy is much less as evidenced by less opioid use asseed through UDT.
l-alpha-acetylmethadol (LAAM) therapy
LAAM therapy for opioid-dependence maintenance treatment which was used initially is discontinued now owning to risks associated with it like prolonged QT interval, incidence of cardiac arrhythmia and death. LAAM was given a black box label by the FDA and is recently banned in the European Union.
Prevention of opioid dependence relapse
Relapse after long periods of abstinence has been reported in individuals experiencing stress. These issues can be evaded by prescribing beta-adrenoceptor antagonist propranolol (beta blockers) as early as after 1 month and as late as 2 years after abstinence. The efficacy of this approach has been proved in a randomized, placebo-controlled trial. Similarly efficacy of injectable, sustained-release form of naltrexone (Depotrex) in preventing stress induced relapsee has also been proved. Catechol-O -methyltransferase (COMT) inhibitors can also provide similar effects. Patients with prominent deficits in apt decision-making can be benefited and prevented from relapsing following this treatment.
Opiate withdrawal is less lethal when compared to barbiturates and benzodiazepines withdrawal in terms of resultant morbidity or mortality. Finalizing the course of detoxification (safe withdrawal form opioids) program, including the decision to perform it as outpatient or inpatient therapy depends several criteria like presence of co morbid medical and psychological problems, social support and involvement of multiple drugs.
Common drugs used in detoxification include
Clinical trials have proved that buprenorphine and methadone treatment is superior to alpha-2 agonists in detoxification. Buprenorphine has a shorter duration of withdrawal symptoms when compared to others.
Psychotherapies and support groups
Standard drug counseling should always be practiced along with detoxification program for achieving complete withdrawal and to prevent relapse. Psychotherapies focusing on cognitive behavioral, supportive, or analytical aspects of patient under methadone programs has found to have positive influence. The efficacy of psychosocial intervention in opioid detoxification was assessed by Cochrane by carefully evaluating 1592 patients undergoing treatment under 11 different studies. Addition of psycho social interventions (behavioral, counseling, and family therapies) regardless of the specific psycho social approach to the pharmacological treatment where found out to significantly reduce dropouts cases and relapses.
Patients with chronic pain (noncancer) who are prescribed with higher doses of opioids owning to their previous drug abuse history are at higher risk of developing addiction. Alternate treatment of pain is thus of paramount importance in such OAT patients.
The physicians ability to choose the most effective treatment increases with clinical experience. Several options are available and the decision to choose one should be made after considering all the associated risk factors. Some of the commonly followed approach include continuation of BMT and titration of a brief-lived opioid analgesic for a positive effect and dividing buprenorphine doses to 6-8 hours break to take advantage of its short-acting analgesic properties. Giving an opioid analgesia treatment when required and stopping BMT and when there is more need for opioid analgesia restarting BMT will be highly recommeded. For inpatient treatment MMT should be adopted along with administration of short-acting opioid as pain medication. Naloxone should be used in case of emergency. Upon discharge continue treatment with BMT.
Improvement in social functions ,reduction of drug abuse and performance at work and school are the factors considered while measuring the success in prognosis. The type of agent used along with external factors (medical care, work status, legal situations, family and psychological problems) will also influence the outcome of prognosis. Relapse rate after opioid treatment varies from 25-97% as evidenced by several studies. Professionals have a much higher success rate when it comes to positive prognosis when compared to patients with poor educational level and income. Cigarette smokers tend to have a higher elapsing rate than nonsmokers.
Research in this field have indicated the role of certain factors contributing to specific substance abuse and in development of related problems. However there is a lack of direct evidence to pinpoint an specific reason for development of any specific drug abuse disorder.
Etiological factors relevant in substance abuse include:
Automation of Reports and Consolidated Orders System (ARCOS) from 2004 to 2011 revealed that there is 100% increase in medical use of opioids and 20% decrease in codeine use. Percentage increase in prescription of other opioids is as follows
Drug Abuse Warning Network`s (DAWN) retrospective data analysis in drug abuse revealed a 384% increase in buprenorphine abuse from 2006 to 2011. Percentage increase of other opioid abuse between 2004 and 2011 is as follows
DAWN`s data also points out that nonmedical drug abuse related to opioid analgesics resulted in 420,040 of the approximately 1.4 million ED visits in 2011.
Key finding in Dart and co worker`s data analysis on Researched Abuse, Diversion, and Addiction-Related Surveillance (RADARS) System from 2002-2013 is listed below. Hydrocodone, hydromorphone, fentanyl, morphine, oxycodone, and tramadol where the prescription opioids selected for the study.
The Centers for Disease Control and Prevention (CDC) in 2012 reported that opioid analgesics were responsible for 72% (16,007 of 22,114) of the pharmaceutical overdose deaths and heroin overdose was responsible for another 5925 deaths.
The major findings from the report of US poison control centers in 2013 on drug abuse is as follows
The report of Centers for Disease Control and Prevention (CDC) in 2012 on drug abuse pointed out that
Propoxyphene, a frequently prescribed narcotic often paired with acetaminophen is found to have a high risk of serious cardiac toxicity. However reports of propoxyphene exposure still continues despite its withdrawal from US market on November 19, 2010 .
Local prescribing tendencies is the deciding factor in etiology of drug overdose cases admitted in ED. Most experienced clinician may find polypharmacy overdoses involving opioids challenging but ability to diagnose the difficult cases through pharmacologic reversal of the opioid component is helpful in management of such cases.
Neurotransmission in the central nervous system (CNS) and peripheral nervous system (PNS) are altered in the presence of opioid. Three main types of opioid receptors along with many less defined receptors with considerably minor effects are activated upon opioid administration.
Opioids use Mu and kappa receptors of CNS and PNS to intercede their physiological effects such as analgesia, respiratory depression and miosis (pupillary constriction). Mu receptors are also involved in evoking euphoria and Kappa receptor activation has a sedative effect. Sigma receptors, which mediate dysphoria, hallucinations, and psychosis; and Delta receptors, which mediates euphoria, analgesia, and seizures are the other two influential opiate receptors.
Opioids group of drugs are generally classified into two groups
Mode of action of opioids is as follows: The perception of pain is decreased upon opioid administration. It should be noted that it has no effect in modulation the stimulus associated with the pain. Opiods are easily absorbed by the mucosal structures of gastrointestinal and respiratory tract rendering an instant effect. Opioid agonists act by lowering the sensitivity to external stimuli and by inducing euphoria.
Subcutaneous ("skin popping") and intravenous ("mainlining") injection are the common methods adopted by street users to administer heroin and morphine . Raw opium is usually consumed or smoked and the powder is sometimes sniffed ("snorted"). Time to attain the maximum effect of opioids is as follows : intravenous route (10 minutes), inhalation of butorphanol, heroin (after 10-15 minutes), intramuscular route (30-45 minutes), oral route (90 minutes) and for dermal application of fentanyl ( 2-4 hours). In case of oral administration, absorption usually take place in the small intestine. Delayed absorption is often reported in case of toxic doses mainly attributed to the delay in intestinal transit time induced by the drugs.
Majority of opioids are metabolized into inactive compounds in liver and is subsequently eliminated from the body through urine. Lipid soluble drugs (e.g. fentanyl, buprenorphine) are stored in adipose tissues of the body. Patients with liver diseases (e.g., cirrhosis) experience a prolonged episode of drug effects owning to the impaired hepatic metabolism. Drug accumulation and toxicity are the common complication reported in such patients. Similarly impaired renal function can also lead to toxic accumulation of drug or its active metabolites (e.g., normeperidine).
Practicing clinicians should seriously consider all the risk factors associated with prescribing opioid medications to prevent a possible abuse or dependence. Information from family, friends and previous health care providers should also be weighed upon before reaching conclusions. Screening of risk factors in patients should be a routine procedure before commencing a long term opioid based therapy. The factors to be screened includes
Screening tools are available to assist physicians in identifying patients requiring intense monitoring under long-term opioids treatment for chronic pain management . Scientifically validated tools includes
Identification of patents with high level risk factors is thus made easy and will help physicians to decide against giving an opiod based treatment at least until the risk factors are addressed properly.
As the accuracy of these screening tools is not 100%, results obtained should not be used to deny treatment, but rather be used to identify patients requiring constant monitoring under long-term opioid treament.
Addiction is a chronic condition with relapsing and remitting nature. It is associated with chronic morbidity and high risk of mortality. Most of the patients presented before medical practitioners have a history of illegal drug addiction.
Opioid addiction (dependence syndrome) is a condition characterized by compulsive drug abuse despite the knowledge of harmful consequences. Continuation of opioid abuse even after sustaining overdoses or associated infections are classic examples. Drug-related impairments (e.g. sedation, overdose) and accidents are common among patients exercising excessive or unsanctioned use prescribed opioid.
Opioid substitution therapy employing drugs like methadone helps in successful management of addiction. This therapy has substantial evidence base to prove its efficacy in improving physical and societal health outcomes. Significant reduction in crimes related to drugs, transmission of blood borne infections and mortality are often observed in patients undergoing substitution therapy. Opioid substitution therapy aids in De-addiction and minimizing health related risks associated with the drug abuse. World Health Organization, recognizing its effectiveness, has included methadone in its Essential Medicines List for treating opioid addiction    .
Opioids commonly known as opiates are a group of drugs mainly used to treat pain. It includes drugs like morphine and codeine which are obtained from the opium poppy plant. Synthetic or partially synthetic chemicals like Vicodin, Percodan, oxycodone and heroin also belong of this group.
Opioids can be administered orally, can be inhaled, injected or smoked. Prescription medication opioid are used as suppositories in some instances. Using prescription pain medications like oxycodone, codeine, and morphine for recreational purpose is regarded as abuse. It should also be noted that using opiods like heroin is illegal and may invite unnecessary legal problems. Consumption of opioids leads our brain to produce intense temporary gratification. Abuse of opioids can rapidly lead to addiction with subsequent life threatening health problems including brain damage especially in case of long term abuse. Addiction will often urge the user do whatever things to procure drugs despite of serious consequences. Addition can affect the patient at two levels
Physical - the body of daily user craves for the drug
Mental - the abuser actively craves for pleasure induced by drugs
Effects of opioid abuse is dependent on the type of opioid and on the way it is consumed. Even a very little use of opioid can lead to addiction. In long run, opioid abuse may hamper brain`s ability to produce the natural pain killers and dopamine (“feel-good” chemical).