Intravenous (IV) prochlorperazine and greater occipital nerve blocks (GONB) must be offered for the acute treatment of migraine in adults in the emergency department (ED), according to the American Headache Society’s (AHS’s) updated guideline on parenteral pharmacologic therapies. However, opioids must not be offered because they are ineffective and potentially harmful, according to the AHS.

The new document was published on December 1 in Headache.

Strong Recommendation

New research about the efficacy of nerve blocks and increased awareness of the risks of opioid use prompted the AHS to explore new evidence on parenteral treatments for patients presenting to the ED with migraine attacks, senior author Serena Orr, MD, pediatric neurologist and researcher at the University of Calgary in Calgary, told Medscape News Canada. Orr led the drafting of the 2016 AHS guideline on parenteral pharmacologic therapies for treating acute migraine in the ED.

“We’ve seen a significant decrease in opioid use since 2016, but there is still too much opioid use in the ED,” said Orr. “Since the 2016 update, there has been emerging research we were all aware of on the use of different types of nerve blocks to treat migraine in the ED. These [blocks] were previously done in headache neurology offices at a tertiary care level, but now we have studies that looked at these nerve blocks in this broader setting.”

The authors conducted a systematic review and meta-analysis using the same methodology as they did for the 2016 guideline. But this time, they expanded their search to include studies of nerve blocks and sphenopalatine ganglion (SPG) blocks. The authors identified 26 new randomized controlled trials that evaluated 20 injectable treatments.

The strong recommendation of GONB to treat adults with migraine in the ED is based on multiple clinical trials that support the treatment’s efficacy and safety. “That’s a big change,” Orr said. “As far as I am aware, there is no other guideline for this particular setting that has made that strong a recommendation. This doesn’t mean that every single person needs to get it. It is a shared decision, and not everyone wants needles in the back of their head, but we are saying it must be at least offered and discussed.”

The second big change is the recommendation to no longer use opioids. “In the 9 years since the last guidelines, more studies have come out on opioid use in migraine that suggest our other options are more effective and safer. For example, we are saying we must not offer hydromorphone. That’s really something we should not be doing,” said Orr.

The new guideline also states that clinicians should offer dexketoprofen IV, ketorolac IV, metoclopramide IV, subcutaneous sumatriptan, and supraorbital nerve blocks. Clinicians may offer chlorpromazine IV, dexamethasone IV, and valproate IV, according to the guideline.

The AHS holds that clinicians should not offer paracetamol IV. It provided no recommendation about eptinezumab IV, parenteral caffeine, granisetron, ibuprofen, ketamine, lidocaine, normal saline, propofol, or SPG blocks.

Skillful Administration

The new guideline is a game changer for patients with migraine, Christine Lay, MD, professor of neurology and director of the headache program at the Temerty Faculty of Medicine at the University of Toronto in Toronto, told Medscape News Canada. “One commonly prescribed class of medications for patients presenting with headache and migraine to the ED is an opioid,” she said.

“Many of us have thought for a long time that it is a suboptimal treatment. There’s really no room for it, but it’s commonly prescribed. Even when the original guidelines came out in 2016, it was still there, and this has definitely taught us that there are better, far more effective medications and procedures. This paper offers us a must-do, must-offer, and the opioids move to never-offer. That’s a critical part of this study,” said Lay.

The guideline also underscores the need for proper training to administer occipital nerve blocks, Lay added. “Occipital nerve blocks need to be done by someone with skill and experience. We are hoping that our emergency medicine colleagues will cooperate and learn and collaborate with neurologists to train and develop the skills and expertise so that this can be done properly, effectively, and safely,” she said.

The must-offer recommendation for nerve blocks is exciting, Candice Todd, MD, a headache neurologist at Temerty Faculty of Medicine and Women’s College Hospital Centre for Headache in Toronto, told Medscape News Canada. “Rarely does a patient come back and tell me that they got a nerve block in the ED, so that recommendation is a huge benefit to patients,” Todd said.

“The other salient piece is that these guidelines highlight the prevalence and the disability that patients with migraine have and the importance of not using opioids. Unfortunately, patients are still getting opioids in the ED. These guidelines emphasize that this is not and should not be the standard of care.”

No funding for the guidelines was reported. Orr reported receiving royalties from Cambridge University Press; serving on the editorial boards of Headache,Neurology, and the American Migraine Foundation; and receiving research funding from the Canadian Institutes of Health Research, the AHS, and the Alberta Children’s Hospital Research Institute. Lay reported having no relevant financial relationships. Todd reported having financial relationships with AbbVie, Teva, Organon, and Lundbeck.