Researchers assess the evidence basis for medications used to treat spine-related pain in older adults

Spine-related pain is increasingly common in older adults. While medications play an important role in pain management, their use has limitations in geriatric patients due to reduced liver and kidney function, comorbid medical problems and polypharmacy (the simultaneous use of multiple drugs to treat medical conditions).

Now a new review study has found acetaminophen is safe in older adults, but non-steroidal anti-inflammatories (ibuprofen) may be more effective for spine-related pain. Non-steroidal anti-inflammatories should be used short-term in lower dose courses with gastrointestinal precaution while corticosteroids show the least evidence for treating nonspecific back pain.

Additionally, nerve pain medications (gabapentin and pregabalin) can be used in older persons, with caution to dose and kidney function. Newer antidepressants (duloxetine) more so than older ones (nortriptyline) can help with spine-related pain, with attention to possible sedation and dizziness. Some muscle relaxants (baclofen and tizanidine) can be used in older persons, again accounting for kidney and liver function. Opioids have limited use in common spine-related pain, but can be used with caution in cases that don't respond to treatment.

Most older people experience neck or low back pain at some point, bothersome enough to see their doctor. Our findings provide a helpful medication guide for physicians to use for spine pain in an older population that can have a complex medical history."

Michael D. Perloff, MD, PhD, corresponding author, assistant professor of neurology at Boston University School of Medicine (BUSM) and a neurologist at Boston Medical Center

The researchers performed a literature review to assess the evidence-basis for medications used for spine-related pain in older adults, with a focus on drug metabolism and adverse drug reactions. They then provided their recommendations based on safe and effective dosing.

Among their findings:

• Pain medicines gabapentin and pregabalin may cause dizziness or difficulty walking, but may have some benefit for neck and back nerve pain (such as sciatica) in older adults. They should be used in lower doses with smaller dose adjustments.
• Some muscle relaxants (carisoprodol, chlorzoxazone, cyclobenzaprine, metaxalone, methocarbamol, and orphenadrine) are avoided in older adults due to risk for sedation and falls. Others (tizanidine, baclofen, dantrolene) may be helpful for neck and back pain, with the most evidence for tizanidine and baclofen. These should be used in reduced doses, avoiding tizanidine with liver disease and reducing baclofen dosing with kidney disease.
• Older antidepressants are typically avoided in older adults due to their side effects, but nortriptyline and desipramine may be better tolerated for neck and back nerve pain at lower doses. Overall, newer antidepressants (namely duloxetine) have a better safety profile and good efficacy for spine-related nerve pain.
• Tramadol may be tolerated in older adults, but has risk for sedation, upset stomach, and constipation. It may be used in lower doses after alternative medications have failed and works well with co-administered acetaminophen. Opioids are avoided due to their side effects and mortality risk, but low dose opioid therapy may be helpful for severe refractory pain with close monitoring of patients clinically.

According to the researchers, complementary medicine, physical therapy, injections and surgery all have a place to help older persons with spine-related pain. "Medications used at the correct dose, for the correct diagnosis, adjusting for preexisting medical problems can result in better use of treatments for spine pain," added first author Jonathan Fu, a 2022 MD graduate from BUSM.

These findings appear online in the journal Drugs & Aging.