Emergency Department Visits — Prevention, Documentation, and Closing the Loop
An ER visit is documented evidence of outpatient treatment failure — use it in PA language, build a rescue plan, and close the loop within one week.
PA impact: This card directly affects prior authorization outcomes. Documentation language from this card can be used in PA letters and appeals.
This card is primarily clinical guidance rather than PA mechanics — its purpose is to help you prevent ER visits, use them as PA evidence when they occur, and manage the handoff back to outpatient care. The cost-effectiveness argument it generates is among the strongest available for approving preventive therapy.
An ER visit is evidence of treatment failure — document it that way. Migraine accounts for approximately one million emergency department visits per year in the United States, and the majority represent a failure of outpatient management: inadequate acute medication, no rescue plan at home, undertreated high-frequency attacks, or escalation of a chronic pattern. Every ER visit for migraine should be documented as a treatment failure with cost data — average ER migraine visit costs $1,500–3,000. This language matters for PA: "Patient presented to [hospital] ED on [date] for intractable migraine not responsive to outpatient acute therapy; this represents a failure of current management necessitating escalation to preventive therapy."
Identify high-risk patients before the next visit happens. Several clinical patterns predict ER utilization: attacks lasting more than 24 hours, no effective rescue medication at home, acute medication limit reached mid-month, and a prior ER visit for migraine within the past year. When you identify a high-risk patient, two interventions reduce ER visits: establish a rescue plan (alternative acute medication route — nasal triptan, injectable sumatriptan, or oral gepant if the primary acute failed) and initiate or escalate preventive therapy.
What happens in the ER — and why opioids are the wrong answer. The 2025 AHS evidence assessment — the most current guideline, published December 2025 — gives IV prochlorperazine its first Level A ("must offer") designation for ER migraine management, supported by multiple Class I studies. Greater occipital nerve block received a Level B ("should offer") designation. IV metoclopramide and IV ketorolac maintain Level B recommendation. Opioids have no Level A or B evidence for ER migraine treatment and carry Level A evidence for harm: opioid use in migraine increases return visits, promotes chronification, and complicates future outpatient management. If the ER record shows opioid administration for migraine, this itself is documentable as a treatment failure that supports the case for preventive therapy.
The Vault generates an ER Preparedness Summary your patient can carry. Patients enrolled in Vault's patient engagement platform can access a one-page ER Preparedness Summary from the app — available offline — that includes their current diagnosis with ICD-10 code, active medications and doses, prior acute treatments tried with response, documented allergies, current preventive therapy, and the treating clinician's contact information. The summary also notes that opioids are not guideline-recommended for migraine and identifies the guideline-supported alternatives.
Status migrainosus is a specific diagnosis — code it when it applies. A migraine attack lasting more than 72 hours despite treatment meets ICHD-3 criteria for status migrainosus. When this occurs — whether managed in the ER or documented in an ER record you receive — code it: G43.011 (without aura) or G43.111 (with aura). Status migrainosus is a powerful PA argument because it documents acute treatment failure with objective temporal criteria.
Close the loop after every ER visit — within one week, not at the next routine appointment. Three things need to happen at that follow-up: review what was administered in the ER and whether it worked (this is clinical information about the patient's acute treatment responsiveness that informs future management); address the reason the patient was in the ER rather than managing at home (was it medication failure, no rescue plan, or severity escalation?); and adjust the treatment plan — a patient who went to the ER for migraine is a patient whose outpatient management is not working. Document the ER visit, the follow-up assessment, and the plan change.
Red flags that belong in the ER, not in a migraine algorithm. A patient presenting with the worst headache of their life reaching maximum intensity within seconds to minutes — thunderclap onset — requires CT and lumbar puncture before any migraine treatment is applied, regardless of prior migraine history. New neurological deficit, altered consciousness, fever with headache and neck stiffness, headache following head trauma, and headache in immunocompromised patients are emergency evaluations, not migraine management.
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Run a PA — free →Citations: 2025 AHS Evidence Assessment (primary citation) — Robblee J et al., Headache 2025 Dec 1. doi:10.1111/head.70016 | 2016 AHS ER Guidelines — Marmura MJ et al., Headache 2016;56(6):911-940 | AHS Consensus 2021 — Ailani J et al., Headache 2021;61(7):1021-1039. doi:10.1111/head.14153 | ICHD-3 status migrainosus criteria (Section 1.4.1).