Medication selection should be driven by rational polypharmacy and take into account such factors as pain type, underlying symptoms, comorbidities, patient preference, and medication side effects.
DALLAS —May 28, 2014—Targeted pain management in multiple sclerosis will be determined by whether the patient is suffering from chronic versus intermittent pain, according to Friedhelm Sandbrink, MD.
Sandbrink, clinical associate professor of neurology at Uniformed Services University in Bethesda, and assistant professor of neurology at Georgetown University in Washington, DC, presented “Pharmacologic Treatment of Pain in Multiple Sclerosis” at the 2014 Annual Meeting of the Consortium of Multiple Sclerosis Centers (CMSC) and the Sixth Cooperative Meeting with Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS).
“The overall message is that with chronic pain associated with multiple sclerosis is that there are different types of pain, and we have to target therapy according to the type of pain the patient is experiencing -- whether it is neuropathic pain vs. musculoskeletal pain, and whether it is steady chronic pain versus intermittent shooting pain,” said Sandbrink.
Medication therapy for pain should be given “in the context of nonpharmacologic treatment,” meaning patients should receive physical therapy and interventional procedures and be taught methods for coping with pain (including cognitive behavioral therapy) and strategies for stress reduction, in addition to medication management.
A stepwise approach is recommended
When selecting medications for the treatment of pain associated with multiple sclerosis, physicians should consider the type of pain the patient is experiencing, any underlying non-MS disorders and coexisting symptoms, comorbidities (such as renal or hepatic dysfunction, bowel or bladder issues, or cardiac complications), the patient’s level of functioning, and the characteristics and side effects associated with each medication being considered.
Sandbrink said medication therapy for chronic neuropathic broad-spectrum pain should include the antidepressant duloxetine for chronic musculoskeletal pain and neuropathic pain, antiepileptics such as gabapentin and pregabalin for the neuropathic pain, and carbamazepine for the sharp, shooting pain associated with trigeminal neuralgia.
Another key issue to consider is if or how to use opioids in clinical practice in this patient population.
For patients with multiple sclerosis who are experiencing neuropathic pain, opioid medications are not recommended as first-line treatment; nerve pain from multiple sclerosis generally does not respond sufficiently to opioid medication to justify its routine use, especially in view of the risks associated with these medications. Thus, it is important to help patients weaned away from the drugs, said Sandbrink.
“However, the individual response to these medications is quite variable, and it is important to use a stepwise treatment approach that gives the greatest pain relief with the fewest side effects,” he said. “Try one medication at a time; if you switch too fast you won’t know what was truly helpful.”
Sandbrink also noted “We have a long list of medications and few guidelines for pain management,” and advised clinicians to consider comorbidities such as depression, anxiety, or sleep disturbance when selecting analgesic medications.
For treating neuropathic pain, the International Association for the Study of Pain (IASP) has issued guidance that recommends the tricyclic antidepressants (TCAs) nortripyline and desipramine, the serotonin and norepinephrine reuptake inhibitors (SNRIs) duloxetine and venlafaxine, and the calcium channel alpha 2â€delta ligands gabapentin and pregabalin as first-line agents.
For localized neuropathic pain, the IASP recommends topical lidocaine, which is available as a patch or gel, as another first-line medication. The use of opioids should be limited to treating acute pain and cancer-related pain, the short-term treatment of episodic exacerbation of severe pain, and when rapid pain relief is needed, as other medications take longer to work.
Sandbrink reminded the audience that when it comes to opioids, “the benefit is short and dependence is an issue. Some patients have worsening of pain over time, when on opioid medication.”
The other big concern
In addition to the patient-centered characteristics of opioid therapy for pain, another important issue that prescribing physicians must contend with is the potential for abuse, misuse, and diversion of these medications. Patients are not always careful in how they store or dispose of their opioid medications, and the drugs can end up being used for nonmedical purposes and cause great harm.
According to data cited by Sandbrink, in 2008 there were 36,450 accidental deaths in the US from drug overdoses, and of 74% of all identified prescription drug deaths involved opioid medication. Opioid prescription drug deaths are responsible for more fatalities than cocaine and heroin combined.
To mitigate this, patients who are candidates for opioid therapy should be assessed and monitored for risk of misuse and abuse, and all treatment decisions should thoroughly documented.
Finally, Sandbrink noted that for patients on high-dose opioid medication and who are at increased risk of overdose, naloxone is available as a rescue kit, and can be lifesaving.