Addiction and dependence Disclaimer: This presentation contains information on the general principles of pain management. This presentation cannot account for individual variation among patients and cannot be considered inclusive of all proper methods of care or exclusive of other treatments. It is the responsibility of the treating physician, or health care provider, to determine the best course of treatment for the patient. Treat the Pain and its partners assume no responsibility for any injury or damage to persons or property arising out of or related to any use of these materials, or for any errors or omissions.

Objectives Discuss the difference between addiction and dependence Review withdrawal, pseudoaddiction, and tolerance 2

Research in the last decade has shown… Risk of developing addictive behaviors as a consequence of medical use of opioids for chronic cancer pain is low Patients, family members, and healthcare workers commonly overestimate the risk of addiction Patients, family members, and healthcare workers often confuse physical dependence and addiction Together, these concerns contribute substantially to physician reluctance or unwillingness to prescribe opioids and patient reluctance to use them Oxford Textbook of Palliative Medicine (2010)3

So, what are the rates of addiction? What proportion of patients using opioids to manage chronic cancer pain will become addicted to opioids? – A. 40% – B. 25% – C. <10% – D. <1% – E. <0.5% 4

Risk of addiction in medical use of opioids The correct answer is E: less than one-half of 1 percent According to the World Health Organization: – A systematic review of research papers concludes that only 0.43% of patients with no previous history of substance abuse treated with opioid analgesics to relieve pain abused their medication and only 0.05% developed dependence syndrome Fishbain et al (2008): Among chronic pain patients with no history of opioid abuse/addiction, incidence of abuse/addiction is 0.19% Ensuring balance in national policies on controlled substances: guidance for availability and accessibility of controlled medicines. World Health Organization (2011). What percentage of chronic nonmalignant pain patients exposed to chronic opioid analgesic therapy develop abuse/addiction and/or aberrant drug-related behaviors? A structured evidence-based review. Fishbain DA et al: Pain Med:

Defining addiction and dependence Addiction: Psychological dependence leading to craving, impaired control over drug use, and compulsive use to get psychic effects despite harm – Behaviours associated with addiction Compulsive drug-seeking Unauthorized use or dose escalation Use despite harm to self or others Oxford Textbook of Palliative Medicine (2010)6

Dependence Dependence: The phenomenon of withdrawal when an opioid is abruptly discontinued – Physical dependence is a normal response to chronic therapy – Prevent withdrawal by titrating the opioid dose down slowly Reduce daily dose by 25% each day Oxford Textbook of Palliative Medicine (2010)7

Withdrawal Signs and symptoms of withdrawal Anxiety Nervousness Irritability Alternating chills and hot flushes Wetness: salivation, watery eyes, runny nose, sneezing, sweating, and gooseflesh At peak intensity of withdrawal, patients may experience: – Nausea and vomiting – Abdominal cramps – Insomnia – Multifocal myoclonus or abrupt spasms (rare) Oxford Textbook of Palliative Medicine (2010)8

Pseudoaddiction When the dose of opioids is not enough to relieve pain, some patients may become anxious about opioid availability and may demonstrate some behaviours that you see in patients with addiction, such as – Asking for the next dose before it is due – Taking medications not prescribed to them – Taking illegal drugs – Using deception to obtain medications Oxford Textbook of Palliative Medicine (2010)9

Pseudoaddiction These behaviours go away after the dose has been increased and pain has been relieved It is important to distinguish pseudoaddiction from addiction: patients with pseudoaddiction stop seeking medications once their pain has been effectively treated Oxford Textbook of Palliative Medicine (2010)10

Tolerance Decreasing response to a drug as a consequence of its continued use An increased dose is required to achieve a similar effect Tolerance to opioids is not common – Increases in opioid requirements are usually related to disease progression Oxford Textbook of Palliative Medicine (2010)11

Take home messages Risk of developing addictive behaviors as a consequence of medical use of opioids for chronic cancer pain is low The risk of addiction is commonly overestimated by patients, family and healthcare workers alike Healthcare workers should be able to distinguish pseudoaddictive behaviors from addictive behaviours When discontinuing morphine, avoid symptoms of withdrawal by titrating the opioid dose down slowly 12

References African Palliative Care Association. Beating Pain: a pocketguide for pain management in Africa, 2nd Ed. [Internet] Available from: African Palliative Care Association. Using opioids to manage pain: a pocket guide for health professionals in Africa [Internet] Available from: Amery J, editor. Children’s Palliative Care in Africa [Internet] Available from: Africa-Full-Text.pdf Kopf A, Patel N, editors. Guide to Pain Management in Low-Resource Settings [Internet] Available from: pain.org/files/Content/ContentFolders/Publications2/FreeBooks/Guide_to_Pain_ Management_in_Low-Resource_Settings.pdf The Palliative Care Association of Uganda and the Uganda Ministry of Health. Introductory Palliative Care Course for Healthcare Professionals