Persistent idiopathic facial pain: Integrating headache neurology insights into interdisciplinary guidelines

The international Delphi study by Lindfors et al. (1) represents an important step toward harmonizing management of persistent idiopathic facial pain (PIFP). Establishing such a rigorous consensus in a rare, heterogeneous condition is an achievement. Lindfors et al. (1) should be commended for assembling a broad interdisciplinary panel. As a headache neurologist, I welcome these efforts while recognizing opportunities for complementary perspectives that could further refine their management framework. In particular, the potential clinical overlap with migraine and neuropathic facial pain, as well as the pragmatic use of pharmacologic therapies, merits further discussion.

The study reports that in retrospect the expert panel “relied on ICOP when diagnosing PIFP”. The International Classification of Orofacial Pain (ICOP) distinguishes PIFP from persistent idiopathic dentoalveolar pain (PIDAP), with the former presenting as facial or mixed facial–oral pain that is poorly localized and not confined to a single tooth, while the latter is limited to an intraoral dentoalveolar site (2). This consensus focused exclusively on PIFP rather than PIDAP. In the Delphi process, a dental examination was considered mandatory (100% agreement). Computed tomography or cone-beam computed tomography of the teeth, jaws and facial structures was recommended (81% agreement) to exclude dental pathology, whereas head magnetic resonance imaging (MRI) was advised only when symptoms warranted (88% agreement). This phrasing effectively prioritizes dental imaging as routine but neuroimaging as contingent. For a condition that can present as facial pain without intraoral pain, proportional emphasis on head MRI may be more appropriate with dental imaging guided by concurrent intraoral or lower facial symptoms. Clarifying the indication for dental assessment versus neuroimaging could promote judicious use of resources and support a more balanced interdisciplinary approach.

The Delphi panel rightly lists “primary headaches and neuropathic pain” among key differential diagnoses, achieving 100% agreement that these conditions must be excluded before diagnosing PIFP. The discussion acknowledges that migraine may present as isolated facial pain, but this distinction receives only brief mention. The recommendations stop short of operationalizing that exclusion as thoroughly as for dental causes. The consensus repeatedly encourages assessment by dentists specialized in orofacial pain, but analogous referral to a headache neurologist is not mentioned.

In practice, the boundary between PIFP and “facial migraine” can be subtle. Migraine features such as photophobia or phonophobia are often unrecognized by patients unless carefully elicited. For example, asking whether they prefer darkness and quiet during severe pain as opposed to simply asking about light and noise sensitivity can identify potentially missed migraine symptoms (3). Without such nuanced history, a migraine diagnosis and corresponding treatment may be missed. Similarly, distinguishing PIFP from trigeminal neuralgia especially with concomitant persistent pain or from painful trigeminal neuropathy requires attention to pain quality, temporal patterns, localization, and sensory findings that then guide a different treatment path. In cases of strictly unilateral continuous pain, hemicrania continua should also be excluded with a brief indomethacin challenge to rapidly distinguish an indomethacin-responsive headache disorder when cranial autonomic features are subtle or unclear (4). Defining an explicit, stepwise process to exclude dental, neuropathic, and primary headache disorders would enhance the utility of these guidelines across disciplines. Currently, the guidelines offer a comprehensive process for excluding dental etiologies; extending this level of detail to other diagnoses would enhance their interdisciplinary utility. It would also promote consistent application in both neurology and orofacial pain practice, encouraging interdisciplinary care.

The consensus commendably discourages invasive dental or surgical procedures while endorsing patient education, behavioral strategies, sleep optimization, and exercise. These principles mirror best practices in chronic pain management. Nonetheless, the discussion conveys a cautious, at times reluctant, stance toward pharmacologic management. Although tricyclic antidepressants, serotonin and norepinephrine reuptake inhibitors, and gabapentinoids are acknowledged, the narrative does not explore how these or other agents might be tailored to phenotype or patient preference.

In clinical practice, many clinicians trial migraine- or trigeminal neuralgia-directed medications, guided by potential phenotypic overlap, as well as patient preference and tolerance. In a condition with no established pharmacologic therapy, therapeutic nihilism can inadvertently lead to hopelessness. Although no controlled study has demonstrated that a purely behavioral approach causes hopelessness, evidence from chronic headache and pain populations repeatedly points to emotional distress, feelings of abandonment, and high rates of comorbid depression and anxiety among patients with persistent pain. When chronic pain is approached primarily through a psychogenic or behavioral lens, patients may feel their pain is not being taken seriously, leading to erosion of the therapeutic relationship and risking a gradual disengagement from care (5). This suggests that in conditions such as PIFP, offering behavioral treatment without also exploring pharmacologic options could create the perception of a shift away from active intervention. Given the paucity of controlled trials, a pragmatic, individualized approach that borrows from neuropathic and migraine paradigms is justified. Explicit endorsement of cautious, structured N-of-1 medication trials could be considered in the absence of evidence-based pharmacologic therapies (6–8). Through shared decision-making, patients can trial well-tolerated medications from adjacent pain paradigms, fostering active engagement rather than perceived passivity or dismissal. Such an approach aligns with the central sensitization and nociplastic mechanisms thought to underlie PIFP, supporting trials of centrally acting medications known to be effective in disorders such as migraine.

The Delphi panel's achievement lies in assembling experts across dentistry, pain medicine, and neurology to articulate shared management principles. The strongest available evidence, as noted by the Delphi consensus, supports patient education and behavioral interventions, particularly cognitive-behavioral therapy. Regular physical activity and sleep optimization were also strongly endorsed as supportive strategies. These approaches are essential given the guarded prognosis and the currently limited efficacy of pharmacologic options. The next step is to translate these principles into integrated pathways that build on this interdisciplinary collaboration. Future efforts could specify the sequence and indications for neurologic and dental evaluations, including thresholds for imaging. They should also include pragmatic pharmacologic algorithms that acknowledge the iterative, trial-and-error nature of real-world clinical care. As our understanding of PIFP evolves, future consensus efforts will benefit from higher-quality evidence to guide pharmacologic, neuromodulation, and procedural management. In the meantime, a patient-centered approach that combines behavioral strategies with individualized pharmacologic trials provides the best opportunity to improve outcomes and to prevent the sense of hopelessness that can accompany chronic facial pain.