Sept. 28, 2016 -- Ketamine, typically thought of as an anesthesia medicine or even a club drug, is now generating a lot of interest among pain management specialists as a useful approach to hard-to-treat migraines and chronic pain.
The use of ketamine against these chronic pain conditions was discussed in separate sessions at the American Academy of Pain Management 2016 annual meeting. In a presentation, Duren Michael Ready, MD, a headache specialist at Baylor, Scott & White Health in Temple, TX, cited research showing that a 25-milligram ketamine nasal spray reduces severity of aura in migraines, and that a 10- to 50-milligram dose is safe for “breakthrough pain” -- sudden flares of severe pain.
In addition, ketamine can address depression, which is often seen in pain conditions such as migraines. According to Ready, 50 milligrams of ketamine nasal spray is effective for treatment-resistant depression.
Ketamine is not for all patients, Ready says. "It's not something you want to pull out for everyone, but it might it be useful for someone not getting better with typical treatments.”
He stresses that ketamine should be prescribed carefully. "You want to kind of limit how often patients use it,” while also making sure they're working to prevent chronic migraines, he says.
Neurologist Hisham Hakim, MD, chairman of the American Spine Center in Birmingham, AL, agrees.
"We need to bring in unusual treatments for those tough cases, such as patients with chronic resistant headache," he says.
In addition to using a topical ketamine cream, migraine patients can use the nasal spray. "These are not doses at a level that will produce sedation, but at levels that can help block the pain," Ready says.
In a separate presentation, Ben Keizer, PhD, of the San Antonio Military Medical Center in Texas, and Justin Boge, DO, of the Evans Army Community Hospital in Fort Carson, CO, discussed, among other things, using ketamine in veterans with a chronic pain condition known as complex regional pain syndrome and post-traumatic stress disorder (PTSD).
They cited reports of the "remarkable" antidepressant effects of low-dose ketamine and successful ketamine treatment of patients with PTSD. It's unclear whether the biggest impact is on the PTSD or the chronic pain, they noted.
A possible treatment for a patient with both PTSD and complex regional pain syndrome could be ketamine therapy along with psychotherapy, Keizer and Boge write. Many doctors "have transitioned from saying 'that's a really powerful anesthetic' to saying 'if we use it in the right dose and in the right arena, it can be very helpful' " for pain, says Robert Bonakdar, MD, director of pain management at the Scripps Center for Integrative Medicine in La Jolla, CA.
Ketamine helps quiet the "hyperexcitability" that can come not only with chronic migraine and chronic pain, but also with other pain conditions (such as phantom limb pain) and functional pain disorders (such as fibromyalgia, irritable bowel syndrome, and chronic pelvic pain), Bonakdar says.
And it can work fast for treatment-resistant depression, he says -- some initial studies show it can bring improvement “within an hour.”
These findings were presented at a medical conference. They should not be considered final, as they have not yet had a "peer review" process, in which outside experts scrutinize the data before it's published in a medical journal.