Ketamine Nasal Spray May Reduce Migraine Pain

A retrospective study at one headache clinic found that intranasal ketamine reduced migraine intensity with relatively tolerable side effects.

Migraine headaches impact about 10% of people worldwide and can be challenging to treat. When this type of headache persists despite treatment, healthcare providers refer to it as refractory chronic migraine.

Ketamine is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist with hallucinogenic, sedating, and pain-relieving effects. While some research suggests the drug might help treat depression, another study found it was ineffective at relieving depressive symptoms.

Since 2000, healthcare providers at Thomas Jefferson University Hospital have been treating chronic pain and headaches with infusions of ketamine. In addition, several randomized controlled trials have found that ketamine may help manage headache pain.

However, ketamine infusions require an IV and careful dose titration and monitoring, which limits its use outside a clinic setting. Finding a better ketamine delivery option could open the door to a new treatment for people with chronic migraines.

That was the goal of a new retrospective study published on May 30 in Regional Anesthesia & Pain Medicine.

Using established patients at the Jefferson Headache Center (JHC), scientists set out to determine whether ketamine delivered intranasally could effectively reduce migraine headache pain and improve quality of life.

Between January 2019 and February 2020, 242 people with refractory headaches used ketamine nasal sprays at a dose of six sprays per day, averaging 10 days of use per month. The scientists then conducted interviews with 169 participants to determine if the treatment had any impact.

Among the interviewed participants, just over 49% reported that ketamine nasal spray was “very effective” at managing pain, and 35.5% said their quality of life was “much better.”

However, 74% reported experiencing at least one adverse event. The most common adverse events were fatigue and double or blurred vision, followed by confusion, dissociation, vivid dreams, or hallucination. Still, slightly over 65% continued to use the ketamine spray.

Despite the promising results, the study authors suggest that healthcare providers should only consider using ketamine in people who are significantly impacted by migraine due to the addictive nature of the drug.

The authors also say that while ketamine nasal spray provided pain relief for some people with chronic migraine in this retrospective study, placebo-controlled trials are needed to fully understand the efficacy, risks, and benefits of this novel treatment.