The Clinical Guide to Supportive and Palliative Care for HIV/AIDS

A Clinical Guide to Supportive and Palliative Care for HIV/AIDS • Chapter 11: Substance Use ProblemsGeneral Pain Management IssuesIn patients with substance use histories, as with other patients, the provider must develop anunderstanding26 picasof the pathophysiology of the pain in question and a rational, incremental approachto its pharmacological management. (See Chapter 4: Pain.) After taking a careful historyof the pain complaint (site; quality; exacerbating and relieving factors; temporal quality; onset;associated symptoms and signs; impact on life and psychology; and effect of current treatments),the provider can determine whether the pain is of nociceptive or neuropathic origin. This distinctionis important as it can have treatment implications. Nociceptive pain results from stimulationof afferent receptors and can cause myriad painful sensations: localized or diffuse; somatic(involving skin, muscle, bone and soft tissue) or visceral; mild to severe. Neuropathic painderives from damaged or otherwise compromised nerves and tends to result in shooting, stabbing,burning, electric shock-like pain, or discomfort that is caused by minimal stimulation tothe skin (allodynia).As is true in any patient, effective pain management in the substance-using patient involvesmultiple modalities and usually requires contributions from all members of the palliative careteam. The pharmacological approach is best guided by the World Health Organization (WHO)three-tiered ladder–starting with non-narcotic analgesics (step one); followed by weak narcotics(step two); and finally moving to strong opioids (step three). (See Figure 4-1 in Chapter 4:Pain.) Adjuvant analgesics can be added at any step (e.g., for neuropathic pain). It is importantto be aware, however, that in a patient who has developed tolerance to narcotics, strong opiates(step three) may be needed sooner, at greater frequency, and at higher doses, than would otherwisebe expected. It is better for the primary care provider to work and be comfortable with oneor two drugs in each class (doses, pharmacokinetics, conversions, side effects, interactions etc.)than to have only a superficial knowledge of all of them. As a general rule, it is best to push lowerlevel treatment to the maximum before advancing to the next level. In cases of moderate tosevere pain, therapy can rightly begin at step two.While taking reports of pain seriously, providers should also act to minimize the likelihood ofabuse. This often means opting for the alternative that is least tempting to the patient, avoidinguse of a stronger, more readily abused drug for mild to moderate pain if an alternative is availablethat is less likely to be abused. For example, codeine is weaker, less euphorigenic, moreconstipating, and of lower “street value” than oxycodone, morphine, or hydromorphone. Althoughthis is not a firm rule, long-acting drugs tend to be less likely to be abused than short-actingones, and certain formulations (e.g., the transdermal fentanyl patch) may be less prone to abusethan others (e.g., brand-name oxycodone pills, which have a higher “street value” than genericoxycodone).As noted above, the concepts of tolerance and dependence are very important in assessing andtreating pain in substance users. (See Tables 11-4 and 11-5.) Because of tolerance, patients willhave higher narcotic requirements than patients who are opioid-naïve, meaning that opioidswill have to be prescribed at higher dosages and more frequently. This is sometimescounterintuitive to providers who are reluctant to prescribe opioids to patients with histories ofopioid abuse. However, unless the provider accounts for the patient’s actual dosage needs, thetreatment will be guaranteed to fail. Moreover, a common scenario which then unfolds is thatproviders may interpret patients’ requests for higher doses or early prescription refills as signsof drug-seeking, thus confirming their prejudices about manipulative behavior in substance users,when in fact this patient response is entirely predictable based on the pharmacology ofopioid medications.XIU.S. Department of Health and Human Services • Health Resources and Services Administration • HIV/AIDS Bureau 261