BOTOX for Chronic Migraine: The PREEMPT Protocol

BOTOX® (onabotulinumtoxinA) has an FDA-labeled indication for the prophylaxis of headaches in adults with chronic migraine. The labeled treatment is a defined head-and-neck protocol; it is not a general instruction to inject every muscle that may be associated with facial or jaw symptoms.

This article is an educational summary for healthcare professionals and patients. It is not injection training, a dosing calculator, or individualized medical advice. Clinicians must use the current prescribing information, their professional training, and locally applicable rules.

The International Classification of Headache Disorders, third edition (ICHD-3), describes chronic migraine as headache on at least 15 days per month for more than three months, with migraine features on at least eight days per month. Diagnosis requires the rest of the ICHD-3 criteria and exclusion of a better explanation.

The FDA indication uses its own labeled wording: prophylaxis of headaches in adult patients with chronic migraine who have at least 15 headache days per month, with headache lasting four hours a day or longer. The label also states that safety and effectiveness have not been established for episodic migraine.

Those definitions are related but not interchangeable. A qualified clinician must establish the diagnosis and determine whether a particular patient is an appropriate candidate.

The FDA prescribing information recommends a total dose of 155 Units divided among 31 sites, with each listed site receiving 5 Units. The sites are distributed across seven specified head and neck muscle areas:

• Frontalis: 20 Units divided among 4 sites
• Corrugator: 10 Units divided among 2 sites
• Procerus: 5 Units in 1 site
• Occipitalis: 30 Units divided among 6 sites
• Temporalis: 40 Units divided among 8 sites
• Trapezius: 30 Units divided among 6 sites
• Cervical paraspinal muscle group: 20 Units divided among 4 sites

The recommended re-treatment schedule in the label is every 12 weeks. This list is a factual summary of the labeled protocol, not procedural instruction; the prescribing information contains the administration details and safety requirements.

Within the labeled protocol, the corrugator and procerus account for three sites and 15 Units in total: one 5-Unit corrugator site on each side and one 5-Unit midline procerus site.

The nearby frontalis is listed separately: 20 Units divided among four sites. Combining the frontalis with the corrugator and procerus when describing the “glabellar region” can produce an incorrect site count. Clinical records should preserve the actual muscle or anatomical zone rather than collapsing separate labeled areas into an ambiguous total.

The masseter does not appear in the FDA label's seven chronic-migraine muscle areas. It is therefore inaccurate to describe masseter injections as a standard PREEMPT site, to add a generic masseter dose to the labeled 155-Unit total, or to imply that an unofficial extended protocol is FDA approved.

Jaw pain, bruxism, temporomandibular disorders, and migraine can coexist, but coexistence does not establish one universal treatment plan. Evaluation and any off-label use require a separate diagnosis, informed consent, individualized risk assessment, and jurisdiction-appropriate professional judgment.

For documentation, the distinction matters: a record should identify which treatment was performed, the clinical indication, product, lot, actual anatomical areas, and units recorded at each site. It should not relabel an off-label area as part of the FDA-approved chronic-migraine protocol.

The current FDA prescribing information reports two randomized, placebo-controlled chronic-migraine studies. At Week 24, the mean change from baseline in headache days per 28 days was −7.8 with BOTOX versus −6.4 with placebo in Study 1, and −9.2 versus −6.9 in Study 2. The label reports statistically significant differences.

These are group averages from controlled studies, not a promise of an individual result. The reduction is measured from each study group's baseline; it is incorrect to say that BOTOX produced eight or nine fewer headache days than placebo.

The clinical studies included doses from 155 to 195 Units, while the labeled dosing table recommends 155 Units at 31 fixed sites. Anyone interpreting trial dosing or considering treatment outside the fixed labeled sites should consult the complete prescribing information rather than infer a protocol from a summary article.

The prescribing information carries a boxed warning about distant spread of toxin effect and contains contraindications, warnings, drug-interaction information, and adverse-reaction data. For chronic migraine in the clinical studies, frequently reported adverse reactions included neck pain, headache, eyelid ptosis, migraine, muscular weakness, musculoskeletal stiffness, and injection-site pain.

A short web summary cannot replace the label. Patients should discuss expected benefits, relevant medical history, alternatives, warning signs, and follow-up with a qualified clinician. Clinicians should consult the current local product information because indications and wording can differ across jurisdictions and can change over time.

A clear treatment record should preserve the indication, date, administering clinician, exact product, lot or batch, total amount used, and the amount recorded for each anatomical area. If an area outside the labeled chronic-migraine protocol is treated for a separate reason, the record should distinguish that indication rather than merge it into “PREEMPT.”

Aesthetic Pass helps practitioners document treatment details, injection-map entries, automatically calculated unit totals, product and lot information, and optional clinical photos. Patients can retain a portable history and share recorded treatment information through the app's protected passport workflow.

Aesthetic Pass is a documentation platform, not a diagnostic system or dosing recommendation tool. Clinical decisions remain with the treating professional.

• U.S. FDA: BOTOX (onabotulinumtoxinA) Prescribing Information — indication, labeled dosing table, clinical studies, boxed warning, and safety information.
• BOTOX ONE: Chronic Migraine Dosing and Administration — current manufacturer professional summary of the 155-Unit, 31-site protocol.
• International Headache Society: ICHD-3 Chronic Migraine — diagnostic description and criteria.

Source review completed July 27, 2026. Always check the current local prescribing information before relying on a dose, indication, or safety statement.