Opioid Prescribing in Dentistry

In order to manage their patients' pain after invasive dental procedures, every practicing dentist must prescribe medication on occasion. Many of these analgesic medications are associated with a high likelihood of physical dependence, as well as a relatively high risk of addiction. As frequent prescribers of pain medication—specifically drugs in the opioid class—it is critical that dentists understand the underlying issues of how these medications work and how they can be abused, as well as exercise sound clinical judgment in identifying patients who might possibly have or develop a physical or psychological dependence on these drugs.

Trends in Prescription Opioid Abuse

The Drug Enforcement Administration reports that approximately seven million Americans are currently abusing prescription drugs that are approved by the Food and Drug Administration (FDA) (Table 1).¹ This exceeds the combined number of people who are abusing cocaine, heroin, hallucinogens, and ecstasy^.1 Subsequently, increased attention recently has been given to the growing epidemic of prescription drug abuse as people throughout the nation, including high-profile celebrities and multitudes of suburban children, die of overdoses.

Opioids are some of the most frequently prescribed medications in the United States, with different brands of hydrocodone (plus acetaminophen) collectively being the most frequently prescribed medications in 2008, and oxycodone (plus acetaminophen) the 25th most-prescribed medication.² While these medications are vital to the treatment of certain types of acute and chronic pain, they also pose a high risk of abuse and addiction with life-threatening consequences.

Three fourths of prescription drug abuse involves painkillers and the prevalence is increasing.¹ The number of patients who have an opioid addiction has nearly doubled from 2000, when 3.8 million Americans were addicted.¹ A study in 2008 reported that 2.9% of 8th graders, 6.7% of 10th graders, and 9.7% of 12th graders had abused Vicodin (hydrocodone 5 mg and acetaminophen 500 mg) and 2.1% of 8th graders, 3.6% of 10th graders, and 4.7% of 12th graders had abused OxyContin (sustained-release oxycodone) at least once in the prior year.³ As a result of the increased incidence of use, the number of new opioid abusers (2,176,000) in 2008 was only slightly less than the new initiates of marijuana use (2,208,000) and cigarette smoking (2,200,000).⁴ This indicates that there are many new users each year, and the prevalence of opioid abuse is predicted to grow.

The increase in prescription opioid abuse may stem from the medications' perceived safety profiles relative to "street drugs," the high quality and potency of the drugs because they are made by pharmaceutical manufacturers, a lesser associated stigma because they are legal when prescribed appropriately, and their relative availability (eg, pharmacies, physicians, dentists, medicine cabinets, friends). Despite the minimal risk of impurities particularly in orally administered legal prescription pain relievers, opioids carry significant liabilities when used inappropriately. With the increase in the prevalence of abuse of these drugs comes a corresponding rise in the number of adverse events, including death, due to the high potency of newer opioid medications as well as an influx of naïve users who have not developed sufficient tolerance to the central nervous system depression caused by these drugs. As a result, a large number of overdoses and deaths are linked specifically to opioids that originated as legally prescribed medications.

The Centers for Disease Control and Prevention (CDC) reports that the number of accidental overdose deaths from opioids or hallucinogens among those 15 to 64 years old increased 83% from 5,921 in 1999 to 10,829 in 2005, and non-fatal unintentional poisonings for those 15 to 64 rose 44% from 376,611 incidents in 2001 to 542,372 in 2007.5 These trends are driven primarily by the growing abuse of opioids.⁵ Recently, the Substance Abuse and Mental Health Services Administration's (SAMHSA) Drug Abuse Warning Network (DAWN) system examined emergency department (ED) visits for non-medical use of prescription drugs (Table 2 and Table 3).⁶ Researchers reported that from 2004–2008 the estimated number of ED visits for non-medical use of opioid analgesics increased 111%, from 144,600 to 305,900 visits, and increased 29% during 2007–2008 alone. The highest numbers of ED visits were recorded for oxycodone, hydrocodone, and methadone. During the 5-year period studied, misuse of oxycodone (eg, OxyContin, Percocet) rose 152% to more than 105,000 ED visits. For products containing hydrocodone (eg, Vicodin, Lortab) ED visits rose 123%, to more than 89,000. Moreover, for the heroin-substitute methadone, ED visits rose 73%, to close to 64,000, and ED visits for hydromorphone (eg, Dilaudid) increased by 259%.⁶

In order not to underestimate the potential for abuse, the prescribing of opioid medications must be carefully evaluated and scrutinized. Despite the serious risks associated with opioid use, these medications are prescribed frequently and often in excessive quantities. To underscore this last point, a recent study in Utah demonstrated that 72% of adults ≥ 18 years old who had been prescribed opioid medication in the previous 12 months reported having leftover medication, and 71% of these people kept the unused pills.⁷

While typically prescribed with excellent intentions to meet a perceived need for pain relief, opioids prescribed by practitioners may be diverted to the streets, particularly if excess medication remains after adequate pain relief has been accomplished. These medications may be abused by the patient, sold or given to others who abuse the drugs, or stolen from medicine cabinets. To limit the possibilities for diversion and addiction, it is essential to ensure that these clinically effective yet potentially dangerous medications are being prescribed only when appropriate, necessary, and in reasonable quantities.

Prescribing Opioids in Dentistry

Although often overlooked as a source of opioid medications, dentists are frequent opioid prescribers. While there is currently no direct evidence, a contribution to non-medical opioid misuse is presumed to be a result of normal prescribing by dentists.

In 2007, the total number of dosage units of opioids dispensed by all practitioners in the United States was 9.4 billion units according to the IMS National Prescription Audit Plus TM.⁸ Despite attempts to monitor the prescribing of controlled substances, there are claims that up to 15% of medications from controlled drug prescriptions are sold on the street^.9 In fact, one third of all drugs that are sold illegally are prescription medications^.9 More specifically, however, many in dentistry might be surprised to learn that dentists were second only to family practice physicians as the specialists prescribing the highest number of immediate-release opioids, amounting to 12.2% of immediate-release opioids in 2002.⁸ Dentists rarely prescribe single-entity opioids, but instead prescribe combination drugs in which a particular dose of opioid is combined with acetaminophen, ibuprofen, or aspirin.^10-15 Wall et al¹⁶ found that analgesic medications comprised more than one third of all prescriptions written by dentists in 2001, second only to antibiotics. Analgesics are the most common medication related to dental visits in patients aged 18 to 30, comprising 40.2% of prescriptions written by dentists in this population^.16 A Drug Utilization Board found that an even higher percentage (53%) of prescriptions written by dentists were for opioids, and that these prescriptions were repeated for the same patient multiple times in some cases.⁹ In this study, a number of the prescriptions exceeded the opioid requirements to treat post-procedural discomfort after most dental procedures.⁹ Thus, it is essential to study opioid prescribing habits by dentists as a potential means of limiting opioid diversion.

While these authors recognize that opioid prescriptions are often deemed necessary to appropriately manage the patient's pain, it may also be suspected that they are frequently prescribed in excess of what is required. There are many factors that may contribute to the prescribing frequency and dosage units of opioids dispensed in dentistry. First is habit. As evidenced by a study¹⁷ in which dentists who had been practicing longer tended to rely more on controlled substances, some dentists may simply be accustomed to prescribing these medications based on their experiences with patients. Despite evidence that non-opioid medications are often sufficient to manage postoperative dental pain and have actually been shown to perform with greater efficacy than opioids in most clinical trials of dental pain,^12,18-21 the dentist may prescribe opioids simply because it is the treatment with which he or she has the most clinical experience and is most comfortable. While all dentists should recognize the necessity to provide adequate pain relief for their patients, many do not acknowledge the efficacy with which non-opioids can manage dental pain, and thus rely heavily on opioid-containing combination drugs.

Second is patient expectations. Many patients assume that there will be a high degree of pain after a procedure and expect and ask the dentist to prescribe opioids to manage this pain. Failing to meet these expectations may result in disagreements with the patient that are unpleasant and require that added chairtime be spent with each patient. Other consequences may include the loss of future appointments with this patient and the potential loss of referrals from this patient or from the patient's general dentist or specialist.

There is frequently a misleading notion in dentistry that because dentists typically prescribe opioids of limited quantity for acute pain, there is minimal risk of addiction. While it may be true that most patients will not become addicts after 15 to 20 doses of opioid combinations, the potential for abuse of this medication remains high. In the survey by Moore et al,²² most oral surgeons reported that they prescribe opioid medications after third-molar extractions. However, many noted that the patient should rely primarily on non-steroidal anti-inflammatory drugs (NSAIDs) and use opioids only after the NSAID fails to eliminate their pain.²² Considering that the average opioid combination prescription is written for 20 dosage units,²² there may often be remaining doses that are not necessary to combat the postoperative dental pain. These pills may be taken by the patient as a recreational drug of abuse or may be stored in the patient's house, incurring a risk of being acquired by a friend or relative for abuse purposes.

Diversion

The patient seen in the dental office who misuses opioids is not always an abuser of the medication himself. Excess pills may be given (diverted) to family members, sold to friends, or sold on the streets. The sale of these excess medications can be quite profitable, especially to 18- to 20-year-old patients, who most commonly undergo third-molar extraction. According to Sejan et al,²³ in 1998, most common street price for Percocet-5^® (5 mg oxycodone plus 325 mg acetaminophen) was $4 per pill, and one can claim up to $1.50 per pill for Tylenol #3^® (30 mg codeine plus 300 mg acetaminophen).²³

Many times, unconsumed opioids are innocently left in one's medicine cabinet in case of emergency need sometime in the future or simply because they are overlooked. These pills may be taken by the patient's children to be abused or sold, or may even be stolen by a houseguest. According to the 2008 National Survey on Drug Use and Health,4 55.9% of people who have used opioids for non-medical purposes report acquiring the pills from family or friends for free. Many adolescents report that their first exposure to this class of drugs is taking these drugs freely from family and friends.⁴ Compounding this number, 14.3% report buying or stealing pills from family or relatives and 18% received the pills from one doctor.4 Only 4.3% actually purchased the drugs from a drug dealer on the streets.⁴

Based on the enormous number of doses of opioids that are prescribed by dental professionals each year (1,146,800,000),⁸ there are undoubtedly pills left over after the dental pain has subsided in many cases. The disposal of such excess medication is not regulated. Therefore, it is highly likely that these pills are major contributors to the large number of prescription opioids that are diverted to the streets. The dentist should, therefore, prescribe opioids with great consideration and caution. Even if the dentist feels that the patient will not become an addict after one prescription of opioids, he or she must recognize that these pills may potentially be contributing to the diversion of opioids to the streets and the growing abuse and addiction associated with opioid medications.

The Drug-Seeking Dental Patient

While there exists great potential to inadvertently disseminate opioids to the streets after prescribing to patients who are not themselves abusing the drugs, addicts or abusers themselves often make appointments to come to the dental office in hopes of obtaining an opioid prescription. In dental school and through other educational materials, each dentist is taught how to recognize the drug-seeking patient. These patients manipulate the doctor through verbal misrepresentation and are often guilty of multiple doctoring. For example, patients may present to an ED to receive opioid medications and may present for multiple emergency dental appointments, often without having the necessary treatment completed that day.²⁴ Other patients may present to a dental office with a history of persistent and multiple oral complaints, complaining of pain in excess of the existing problem and claiming to have allergies to over-the-counter or non-opioid pain medications. They often insist that non-opioid medications have not been strong enough in the past and suggest an opioid that a previous dentist had prescribed. The patient may claim to be too busy that day to be treated, but assures the dentist that he or she will return soon for treatment. The patient, however, does not ever follow through with treatment.²⁵ Furthermore, to obtain even a small amount of medication, some patients will call after hours begging for medication to decrease their pain until their emergency appointment the next day, to which they will not show up. New dentists to a region or very busy practices in which the patient believes that the dentist will not call a physician to verify his or her medical history are primary targets of drug-seeking patients. If the dentist is suspicious of an emergency patient, he or she may consider dispensing only one day's dose of an analgesic and seeing if the patient returns for treatment. In doing this, the pain is managed without contributing significantly to potential abuse of the medication if the emergency is a fraudulent attempt to obtain opioids.²⁴

Some common behavioral signs that may be helpful in identifying an addict include lack of hygiene and disheveled appearance, extraordinary efforts to cover arms and wrists to conceal any evidence of intravenous (IV) drug use, or inappropriate use of sunglasses to conceal dilated (in the case of opioid withdrawal) or constricted (in the case of recent opioid use) pupils or bloodshot eyes.²⁶

Patients who are in early stages of opioid withdrawal and may be looking for a "fix" often exhibit excessive sneezing, yawning, and restlessness. If currently taking opioids, a patient will often have pinpoint pupils, thirst, slurred speech, and a red nose due to frequent scratching caused by the histamine-releasing capabilities of opioids.²⁶

While the above signs are helpful to use as guidelines for identifying a drug-seeking patient, these signs may not always be evident. Drug-seeking patients are often highly educated, manipulative, sophisticated, and successful at obtaining their desired drug. They know the correct terms used in oral pathology and have mastered the ability to mimic the signs and symptoms of dental abscesses, temporomandibular joint pain, or facial pain.²⁵ Thus, it may be very difficult to determine that a patient is seeking medication rather than experiencing pain. When an addict needs to sustain a high, he or she will go to great lengths to obtain the drug and can make a convincing and deceiving argument for his or her case.

Additionally, addicts may be difficult to detect because, despite common misconception, low socioeconomic conditions are not required for the development of drug abuse.²⁶ In fact, in a 2005 survey, almost 10% of dentists reported using drugs during the previous year.²⁷ Because of the fact that opioids are expensive street drugs and are potentially associated with less stigma than most other drugs, many opioid addicts may not fit the stereotypical appearance of an addict. Anecdotal experience reveals that prescription-opioid addicts may be more likely to come from middle- or upper-class families, be educated, and appear well groomed and well dressed. One may be less suspicious of drug-seeking motives when treating a patient who resembles their next-door neighbor. Thus, an extra level of precaution must be used when prescribing opioids because of the fact that opioid addicts are typically difficult to identify and are capable of manipulating the practitioner into believing that a prescription is necessary.

Ethical Considerations

There is an ongoing conflict in the field of dentistry that arises in relation to opioid prescriptions. The dentist's primary obligation is to the patient. In accordance with the American Dental Association Code of Ethics, the dentist is committed to beneficence (do good) and non-maleficence (do no harm).²⁸ Postoperative dental pain is an important means of evaluating the healing process and preventing further unintentional injury. However, unmanaged dental pain may prevent the patient from resuming daily life and the dentist has a responsibility to appropriately manage the dental pain of the patient. Severe postoperative pain may promote the development of hyperalgesia and heightened discomfort in later stages of healing. Such pain may also supplement a patient's apprehension about dental treatment and result in the patient neglecting and delaying dental care in the future.²²

There is also an obligation to avoid facilitating the abuse of opioid medication. One must consider both clinical and social facets of this commitment. These obligations are consistent with the Code of Ethics²⁸ in that all measures are being taken to protect the health of the patient. One should strive to protect the patient from the health risks of addiction or abuse of any drug. The dentist's clinical responsibilities include learning to detect the physical and behavioral signs of drug abuse, and familiarizing oneself with tactics used by patients to obtain drugs for abuse or for diversion to others.²⁶ The practitioner must be prepared to respond appropriately to such strategies and understand the therapeutic complications that may arise during the treatment of a patient who is abusing drugs.²⁶ It is important to understand that the first symptoms of addiction are often denial and the loss of rational self-control, thus making notions of patient competency uncertain. Therefore, the practitioner must have the clarity of purpose to understand that protecting the patient requires ignoring the patient's verbal input when it appears to be compromised by a substance-use disorder, and protecting the patient "despite himself."

Furthermore, the dentist has an obligation to recognize the signs of substance-abuse disorders and refer patients suspected of drug abuse to an addiction treatment program for further evaluation and possible treatment. Failure to do so is analogous to suspecting an oral malignancy and failing to bring the appropriate consultants on board to make a definitive diagnosis and begin therapy. The dentist also has a responsibility to society to strive to minimize the overall amount of opioid prescriptions that are diverted to the streets, thus decreasing the nationwide misuse and abuse of and addiction to opioid medications.

Many consider the responsibility of the dentist to manage the patient's pain and the obligation to minimize potential opioid abuse or diversion to be mutually exclusive. In dentistry, there seems to be a frequent misconception that one must choose between these two goals, and most frequently the dentist chooses to prescribe opioid-combination drugs to manage potential postoperative pain with limited regard to the possibility of diversion. However, these responsibilities do not necessarily require choosing between conflicting treatments. The dentist should strive for adequate pain management while simultaneously assuming the responsibility of limiting the potential for drug abuse or diversion.

Conclusions and Recommendations

In efforts to ensure appropriate opioid prescribing in dentistry, the mentality surrounding pain medication and overall treatment must be modified. Once the source of the patient's pain (usually an infected tooth) is removed, the pain will subside. Atraumatic treatment and care taken to minimize trauma to surrounding tissues are likely to reduce pain significantly. In most instances, NSAIDs have been demonstrated to be more than adequate at relieving postoperative dental pain^{.9,12,15,17-21,29,30} In fact, most comparative studies suggest that NSAIDs are superior to opioids in relieving dental pain, with fewer side effects.^12,15,18-21 When prescribed, opioids should be employed to supplement the analgesic effects of NSAIDs or acetaminophen.

While there are cases that warrant the prescribing of opioid-containing drugs for the management of dental pain, these prescriptions should be written with discretion. Currently, opioids are routinely prescribed in cases that could often be appropriately managed with NSAIDs and are also prescribed in excess quantities in many dental prescriptions.^7,22 Anecdotal and correlative evidence seems to provide substantial support for the notion that dental opioid prescriptions may inadvertently contribute considerably to the growing nationwide abuse of opioid drugs. Contrary to common belief, however, the dentist does not have to choose between providing adequate pain relief to his or her patient and preventing opioid diversion. With attempts to alter the attitudes of patients and dentists, the dentist can manage the pain of the patient through careful procedural techniques, NSAID use, and limited opioid prescriptions of appropriate quantities when deemed necessary. Using good clinical judgment, the dentist can fulfill his or her obligation to manage the pain of the patient, to protect the patient from unnecessary medication and abuse potential, and to maintain his or her societal responsibility to limit the diversion of opioids to the streets.

Further research is needed to determine the frequency with which dental opioid prescriptions are diverted to the streets or abused by patients. Research should also be undertaken to determine the number of excess doses of opioids that are prescribed and remain unused by the patient.

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About the Authors

Stephanie Golubic, DMD, MBE
Orthodontic Resident
University of North Carolina School of Dentistry
Chapel Hill, North Carolina

Paul A. Moore, DMD, PhD, MPH
Professor of Pharmacology
Chair, Department of Dental Anesthesiology
School of Dental Medicine
University of Pittsburgh
Pittsburgh, Pennsylvania

Nathaniel Katz, MD
Adjunct Assistant Professor of Anesthesia
Tufts University School of Medicine
Boston, Massachusetts

Program Director
Tufts Health Care Institute Program on Opioid Risk Management
Boston, Massachusetts

George A. Kenna, PhD, RPh
Assistant Professor of Psychiatry
Center for Alcohol and Addiction Studies
Brown University
Providence, Rhode Island

Senior Scientific Advisor
Tufts Health Care Institute Program on Opioid Risk Management
Boston, Massachusetts

Elliot V. Hersh, DMD, MS, PhD
Professor and Division Director of Pharmacology
Oral and Maxillofacial Surgery Pharmacology
School of Dental Medicine
University of Pennsylvania
Philadelphia, Pennsylvania