Patients using the treatment reported reduced headache intensity and better quality of life.
Intranasal ketamine could serve as an acute treatment for refractory chronic migraines and help improve patient quality of life, according to new research data published in Regional Anesthesia and Pain Medicine.1
Previous studies have shown ketamine to be an effective treatment for headache management when given as a subanesthetic infusion, but this method of administration requires monitoring by a pain specialist in a hospital, which limits its use in an outpatient setting.
However, intranasal ketamine is an attractive alternative due to its ease of storage and simple route of administration, especially for patients who have not responded well to other forms of treatment.
"It's for patients who've tried several other treatments that haven't been effective and for patients that are really disabled or significantly disabled by their pain," Michael Marmura, an author on the study and a headache specialist at Thomas Jefferson University, told HealthDay.2
Investigators conducted a retrospective study to assess the clinical effectiveness and tolerability of intranasal ketamine in patients with refractory chronic migraines. Data was gathered from electronic medical records of patients who received intranasal ketamine from January 2019 to February 2020.
The cohort in the study included 242 patients with a median age of 44, of which 79.9% were women. Patients reported a median of 30 headache days per month, as well as having already tried 4 classes of preventive medication.
The intranasal ketamine was formulated by a local compounding pharmacy to approximately 10 mg per 0.1 mL spray, and patients were instructed to use 1 to 2 sprays in each nostril per dose every 15 minutes as needed, with up to 20 sprays a day and 40 sprays a week at the discretion of their health care provider.
Investigators found that 49.1% of participants reported that the intranasal ketamine was very effective, while 39.6% said the treatment was somewhat effective. Additionally, 35.5% of patients reported that their quality of life was much better.
Overall, the study participants used 6 sprays of the intranasal ketamine per day, with a median spray use of 10 days per month.
When compared to other treatments, 43% of patients thought the intranasal ketamine was much better and 29.5% felt it was somewhat better. At the time of the study interview, 65.1% of participants remained users of the treatment.
At least 1 adverse event was reported by 74% of patients. The most common were fatigue and double or blind vision, followed by cognitive adverse events, which included confusion or dissociation, vivid dreams, and hallucination.
"This is not something that we suspect will be widely adopted, but I think that there may be a role for this for some of our most refractory patients," said Marmura. "It appears to have an acute effect and for some patients, it may help their quality of life or prevent migraine down the road."2