Pain Control in Heroin Addicts

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Pain Control in Heroin Addicts
SHEILA MODI
BEST PRACTICES CONFERENCE
MAY 16, 2012
(Real) Case 1
• R.C., a 44 yo M with active IVDU (heroin) admitted
with R hand abscesses and severe cellulitis, s/p I&D,
on IV antibiotics.
• PMHx:
–
HCV, poorly controlled DM2, sciatica with chronic low back
pain, neuropraxia LUE s/p fall in 2003, chronic LE ulcer,
multiple skin abscesses
• Patient requests transfer of physicians because he
feels his pain is not being adequately controlled and
he feels stigmatized due to his IVDU.
Case 1 (cont’d)
• Subjective:
– Pt c/o R hand pain, but more concerning to him is his lower back
pain/sciatica with pain going all the way from R neck down to R buttocks
to just above his R ankle. He says this is worse than previously. He also
c/o chronic liver pain.
– He denies current heroin withdrawal symptoms, denies diarrhea, diffuse
muscle aches. He does report some yawning and anxiety/irritability. He
feels the opiates he is getting have been sufficient to prevent withdrawal
symptoms.
– He says that in the past, he has taken up to 300 mg morphine per day
which did not control his pain as well as IV dilaudid; he is requesting
dilaudid 2 mg IV q4 hours scheduled. He says he knows that dose is
sufficient to control his pain.
– He is not interested in quitting heroin; the first thing he will do upon
discharge is go use heroin. He states he will not use heroin as an
inpatient because he understands the risks for overdose when combined
with narcotic pain medications. He understands he will not be
discharged with any pain medications.
Case 1 (cont’d)
• Current pain control regimen:
– Acetaminophen 650 mg po q4 hours PRN pain
– Methocarbamol 1000 mg po q6 hours PRN pain
– Oxycodone 5-10 mg po q4 hours PRN pain
– Morphine 2-4 mg IV q2 hours PRN pain
• New pain control regimen:
– Dilaudid 2 mg IV q4 hours scheduled
– Acetaminophen PRN pain, max 2 grams/day
– Patient counseled that this dose will not be escalated
Case 1 (cont’d)
• Follow-up: The patient did well on this dose: he was
happy, cooperative, felt his pain was reasonably well
controlled, and we never escalated dose, he was not
discharged with any pain meds.
• Reactions from other physicians (not exact quotations):
–
–
From the transferring physician: What is wrong with you: why are
you giving a heroin addict IV dilaudid?
From the physician I handed off care to: What is wrong with you:
why are you giving a heroin addict IV dilaudid?
• My reaction: I think I’ll do a best practice talk on this
topic-- we see this all the time, and we all handle it
differently.
Objectives
 Increase our basic understanding of pain and its
relationship to opioid addiction
 Identify our own misconceptions that may prevent
us from adequately treating pain in this population
 Provide general recommendations on how to
approach pain management in these patients
Definition of Pain
 Pain = an unpleasant sensory and emotional
experience, associated with actual or threatened
tissue damage, or described in terms of such.

International Association for the Study of Pain (IASP)
 What this means:
 Pain is subjective
 Has both sensory and affective components


Influenced by genetics, sociocultural expectations, gender, cooccurring medical or psychiatric conditions, and other factors.
Can exist in the absence of actual tissue pathology
Acute vs. Chronic Pain
Acute Pain
Chronic Pain
 Abrupt onset
 Pain may persist for variety of
 Usually associated with an
acute physical condition
 Self-limited, resolves as
underlying cause resolves
 Associated with sympathetic
responses: increased BP and
pulse, sweating, blanching of
skin, hyperventilation; pts
appear distressed
reasons
 Chronic pain causes secondary
problems: sleep disturbance;
anxiety; depression; loss of
normal function in work, social,
recreational areas; increased
stress due to these losses
 Effective treatment for chronic
pain should be multifactorial
 No sympathetic arousal; pts
may not appear distressed
Pain in heroin addicts
 Pain and addiction reinforce each other
 Current opioid addicts have been shown to be less tolerant of pain5,7

Both in threshhold (when pain is reported) and tolerance (how long can
withstand pain)
 Pain experience is exacerbated by subtle withdrawal symptoms, sleep
disturbance, and affective changes.
 Pain is more difficult to treat due to:



Tolerance and cross-tolerance
Opioid-induced hyperalgesia
Multifactorial etiology
 Most pain complaints are driven by real distress4

Patients with co-occurring pain and addiction may have difficulty knowing
where pain ends and cravings for opioids begins
Drug-seeking behavior
• “Drug-seeking behavior” is a widely-used but poorly
defined term, may be explained by:
–
–
–
–
Pseudo-addiction
Pseudo-opioid resistance
Patients with a h/o substance abuse have experienced
immediate distress-reduction; commonly-used long-acting
opioids will not provide this  different expectations between
physicians and patients  frustration by both parties
Patient’s fears of being stigmatized may lead them to hide their
substance abuse history for fear that needed pain medication
may be withdrawn
Source: Rowley D, et. al. Review of cancer pain management in patients receiving methadone maintenance therapy. AM J HOSP
PALLIAT CARE 2011 28: 183
Opioid-induced hyperalgesia
 Caused by up-regulation of NMDA receptors
which cause an increased sensitivity to pain
and reduce the analgesic efficacy of opioids
Current opioid-dependent subjects are less pain tolerant
than controls in the cold-pressor test
 Another study showed that negative affect heightens OIH
in heroin addicts2

•
Sources:
1. Ho A, et. al. Pain response in heroin users: personality, abstinence, and modulation by benzodiazepines. Addictive
Behaviors. 2011 36:1361-1364.
2. Carcoba LM, et. al. Negative affect heightens opioid- withdrawal induced hyperalgesia in heroin dependent
individuals. J Addict Dis. 2011 Jul-Sept 30(3):258-70.
Common misconceptions of health providers that result in
the under-treatment of acute pain


The maintenance opioid agonist (methadone or
buprenorphine) provides analgesia
Use of opioids for analgesia may result in addiction
relapse



Relapse prevention theories state that the stress associated with
unrelieved pain is more likely to trigger a relapse than adequate
analgesia
Concern for respiratory and central nervous system
(CNS) depression
The pain complaint may be a manipulation to
obtain opioid medications, or drug-seeking,
because of opioid addiction
Source: Alford DP, et. al. Acute pain management for patients receiving maintenance methadone or buprenorphine therapy. Ann Int Med 2006 Jan 17;
144(2):127-134.
Doctors provide less pain control for heroin
addicts
 A study of 516 HIV patients with cancer pain
showed:

Pts with a h/o substance misuse were less likely to be
prescribed strong analgesics than those with no such history
and thus reported more uncontrolled symptoms and more
psychiatric distress than other patients
Source: Rowley D, et. al. Review of cancer pain management in patients receiving methadone maintenance therapy. AM J HOSP
PALLIAT CARE 2011 28: 183
Ethics
 Untreated pain can cause psychiatric and medical
morbidity: affective and anxiety disorders, adverse
immune system changes, central neurologic changes
such as spinal cord sensitization (violates “do no
harm”)
 Offering opioid treatment to these patients utilizes
principles of beneficence and justice.
Recommendations
Key principles in acute pain management in
opioid dependent patients
 For patients on chronic opioid therapy (either methadone or other
opioids), the established daily dose will not provide analgesia for acute
pain
 Pts will have tolerance and will require higher doses at more frequent
intervals
 Prescribing scheduled, long-acting, or continuous opioids will avoid
compelling the patient to request opioids frequently, which may be
misinterpreted as drug-seeking

Use PRN for dose-titration only
 For individuals in recovery, an intensification of recovery activities may
reduce the risk that medical challenges and opioid therapy will trigger
relapse
 In periods of medical challenge (e.g. illness, surgery, trauma), pts with
active addiction may be especially amenable to entering addiction
treatment
Patients on Methadone Maintenance Therapy
• Continue methadone at same dosage and use a
different medication for acute pain
•
Use opioids
–
–
•
Adequate pain control will generally necessitate higher doses of
opioid analgesic administered at shorter intervals.
Analgesic dosing should be continuous or scheduled, rather than
as needed. Allowing pain to reemerge before administering the
next dose causes unnecessary suffering and anxiety and increases
tension between the patient and the treatment team.
Also use other analgesics (e.g. acetaminophen) and adjuvants
(e.g. TCAs)
Source: Alford DP, et. al. Acute pain management for patients receiving maintenance methadone or buprenorphine therapy. Ann Int Med 2006 Jan 17;
144(2):127-134.
Pain control in cancer patients on MMT
• 12 patients:
– 80% had difficult to control pain
– All patients required adjuvants in addition to opioids (e.g.
paracetamol, NSAIDs, neuropathic agents)
– Multiple analgesic agents required in 70% of patients
–
2 patients (17%) documented as having drug-seeking
behavior (1 for benzos, 1 for opioids)
Source: Rowley D, et. al. Review of cancer pain management in patients receiving methadone maintenance therapy. AM J HOSP
PALLIAT CARE 2011 28: 183
Patients on Buprenorphine Maintenance
 Buprenorphine is a partial agonist which binds avidly to mu
opioid receptors and will block action of other opioids
 Possible strategies:

Discontinue buprenorphine (but there will be prolonged effect) and
aggressively titrate opioids to sufficiently high doses to overcome the
blockade. Recommend IV fentanyl which also binds avidly to mu
opioid receptors.


This should be done by an experienced clinician, with naloxone on hand,
and close monitoring
Take their maintenance daily dose, increase it, and give it q6 hours.

However, doses of 16-32 mg per day will saturate the mu receptors (and
only partially activate them) so there is a ceiling to buprenorphine’s
analgesic effect.
Patients who are active heroin
users
Equivalent doses
 Dilaudid 1 mg IV = 20 mg po morphine
 Dilaudid 2 mg IV q4 hours = 240 mg po morphine
per day
 What is the equivalent dose of heroin?
Heroin dosing
•
Heroin 5 mg IV = methadone 20 mg po = morphine 30 mg po1
•
Average “hit”= 20-25 mg IV heroin3 (~600 mg po morphine)
•
•
•
Average user 466 mg/day IV heroin = 2,796 mg morphine po/day2
•
•
•
Varies depending on tolerance and purity
1 gram street heroin DOES NOT EQUAL 1 gram pure heroin
so these calculations are merely approximations
Other sources quoted slightly lower doses, e.g. 300 mg heroin/day =
1800 mg morphine po3.
No one knows for sure….
Sources:
1.
2.
3.
Anderson IB and Kearney TE. Medicine cabinet: use of methadone. West J Med 2000 January; 172(1):43-46.
Perneger TV, et. al. Patterns of opiate use in a heroin maintenance programme. Psychopharmacology 2000 July; 152: 7-13.
http://www.justiceforkurt.com/investigation/dmdpt/table3.shtml
Recommendations for pain control in heroin
addicts
 Give patients complaining of pain the benefit of the






doubt
Up-titrate opioids until pain control achieved
Schedule dosing of opioids (use PRN only for uptitration)
Switch to long-acting preparations early
Switch from IV to po early
Do not also use benzos
Closely monitor (and re-assess after visitors)
Sources
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Anderson IB and Kearney TE. Medicine cabinet: use of methadone. West J Med 2000 January;
172(1):43-46.
Perneger TV, et. al. Patterns of opiate use in a heroin maintenance programme. Psychopharmacology
2000 July; 152: 7-13.
http://www.justiceforkurt.com/investigation/dmdpt/table3.shtml
Savage SR, et. al. Challenges in using opioids to treat pain in persons with substance use disorders.
Addiction Science & Clinical Practice. 2008 June: 4-25.
Alford DP, et. al. Acute pain management for patients receiving maintenance methadone or
buprenorphine therapy. Ann Int Med. 2006 January 17; 144(2): 127-134.
Rowley D, et. al. Review of cancer pain management in patients receiving methadone maintenance
therapy. Am J Hosp Palliat Care 2011 28: 183.
Ada Man Choi Ho, et. al. Pain response in heroin users: Personality, abstinence, and modulation by
benzodiazepines. Addictive Behaviors 36 (2011) 1361-1364.
Cohen MJM, et. al. Ethical perspectives: Opioid treatment of chronic pain in the context of addiction.
The Clinical Journal of Pain 2002; 18:S99-S107.
Basu S, et. al. Pharmacological pain control for HIV-infected adults with a history of drug dependence.
J Subst Abuse Treat. 2007 June; 32(4):399-409.
Ballantyne JC, et, al. Review: opioid dependence and addiction during opioid treatment of chronic
pain. Pain 2007. 129; 235-255.
http://www.emcdda.europa.eu/attachements.cfm/att_35646_EN_COWS.pdf
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