Anticonvulsants as an Alternative to Opioids in Managing Chronic Pain
Chronic pain is an increasingly prevalent issue, affecting almost 1.5 billion people worldwide1. It has always been a challenging problem to deal with, and for over many decades, physicians have commonly prescribed opioids to help manage this pain2. However, opioids have highly addictive properties2. Because of this, medical professionals are shifting towards alternative treatments for managing chronic pain. One type of treatment that is still pharmacological in nature is prescribing non-opioid medications such as anticonvulsants3. These are considered to be “adjuvant medications,” meaning that they have analgesic properties3. Research has shown anticonvulsants to vary in how effective they are in managing chronic pain.
Wiffen et al. (2000) conducted a meta-analysis of twenty three randomized controlled trials where anticonvulsants were used to manage acute, chronic, and cancer pain. Looking at six different anticonvulsants over the various studies, the researchers found that overall, anticonvulsants were not highly analgesic4. However, there were a handful of instances where anticonvulsants, in particular carbamazepine, had an analgesic effect for patients with chronic neuropathic pain4. Since this meta-analysis is now 20 years old, there have been more recent meta-analyses by the same authors on newer randomized controlled trials. Wiffen et al. (2011) looked at fifteen different studies, finding again that carbamazepine is a fairly effective anticonvulsant in managing chronic pain5. The researchers, however, noted that more research is needed for a better understanding of how this treatment can be a viable option for managing chronic pain, such as by examining the effects of different doses5.
Moore et al. (2014) conducted another literature review but specifically looked at the anticonvulsant, gabapentin, for chronic neuropathic pain6. Examining randomized, double-blind studies, the researchers focused on the analgesic effects of gabapentin. An important finding of theirs was that a majority of patients reported at least a 35% reduction in pain intensity with gabapentin compared to a 21% reduction with a placebo6. However, these results varied between different types of chronic pain conditions, as well as the dosage of gabapentin prescribed6. Overall, there does seem to be some efficacy in using the anticonvulsant, gabapentin, but additional research is needed in order to determine what type of chronic pain this anticonvulsant would be most optimal in managing.
Finally, a more recent review by Derry et al. (2019) looked specifically at the anticonvulsant, pregabalin, for managing chronic pain7. The review determined that prescribing oral pregabalin for people with chronic neuropathic pain displayed promising results7. However, this was only true for those experiencing pain after shingles or diabetes and not for those experiencing pain due to injuries such as strokes7. Evidently, pregabalin is an efficient alternative for managing chronic pain, but for only specific types of chronic pain, similar to Moore et al. (2014)’s findings about gabapentin6,7. This indicates that different anticonvulsants are optimal for different types of pains.
Given that much of the current literature finds varied effects of using anticonvulsants, it appears as though there is a need for increased research on this therapy for managing chronic pain. There are many different types of anticonvulsants, and each medication produces different analgesic effects. Thus, additional research is necessary in determining which anticonvulsant is optimal for each type of chronic pain. By doing so, medical professionals can then be certain in prescribing this pharmacotherapy as a better alternative for managing chronic pain.
References:
(1) Cirino, E. (2018, September 2). Causes of Chronic Pain. Retrieved from
https://www.healthline.com/health/chronic-pain
(2) Module 2: Treating Chronic Pain without Opioids. Retrieved from
https://www.cdc.gov/drugoverdose/training/nonopioid/508c/index.html
(3) Center for Substance Abuse Treatment. Managing Chronic Pain in Adults With or
in Recovery From Substance Use Disorders. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2012. (Treatment Improvement Protocol (TIP) Series, No. 54.) 3, Chronic Pain Management. Available from: https://www.ncbi.nlm.nih.gov/books/NBK92054/
(4) Wiffen PJ, Collins S, McQuay HHJ, Carroll D, Jadad A, Moore A, Fairman FS.
Anticonvulsant drugs for acute and chronic pain. Cochrane Database of Systematic Reviews 2000, Issue 3. Art. No.: CD001133. DOI: 10.1002/14651858.CD001133.
(5) Wiffen PJ, Derry S, Moore RA, McQuay HJ. Carbamazepine for acute and chronic
pain in adults. Cochrane Database of Systematic Reviews 2011, Issue 1. Art. No.: CD005451. DOI: 10.1002/14651858.CD005451.pub2.
(6) Moore, R. A., Wiffen, P. J., Derry, S., Toelle, T., & Rice, A. S. (2014). Gabapentin for
chronic neuropathic pain and fibromyalgia in adults. The Cochrane database of systematic reviews, 2014(4), CD007938. https://doi.org/10.1002/14651858.CD007938.pub3
(7) Derry S, Bell R, Straube S, Wiffen PJ, Aldington D, Moore R. Pregabalin for
neuropathic pain in adults. Cochrane Database of Systematic Reviews 2019, Issue 1. Art. No.: CD007076. DOI: 10.1002/14651858.CD007076.pub3