PO-48 | Flunarizine for preventive treatment of hemiplegic migraine during pregnancy: a case report

Andrea Burgalassi,¹ Antonio Munafò,² Francesco De Cesaris,¹ Giulia Vigani,² Alberto Chiarugi^1,2 | ¹Headache Center and Clinical Pharmacology Unit, Careggi University Hospital, Florence, Italy; ²Section of Clinical Pharmacology and Oncology, Department of Health Sciences, University of Florence, Florence, Italy

Background: Hemiplegic migraine (HM) is a rare subtype of migraine characterized by reversible motor weakness accompanying visual and sensory aura symptoms. HM is classified as either sporadic (SHM) or familial (FHM). FHM has been linked to mutations in the CACNA1A, ATP1A2, and SCN1A genes, and more recently to PRRT2 and SLC1A3. Commonly used preventive treatments include flunarizine, verapamil, sodium valproate, acetazolamide, and lamotrigine. No specific treatment guidelines exist for HM during pregnancy. Migraine symptoms often improve during pregnancy, with up to 70% of patients reporting remission by the second trimester. However, persistent migraine may require treatment due to increased maternal risk (e.g., gestational hypertension, preeclampsia, and venous thromboembolism) and adverse neonatal outcomes (e.g., preterm birth, low birth weight). We report the first documented case of a woman with FHM treated with flunarizine during pregnancy.

Case presentation: A 24-year-old woman with genetically confirmed FHM (PRRT2 mutation) experienced frequent migraine attacks (10–12 days per 28-day cycle) with severe, unilateral, pulsating headache, accompanied by nausea, photophobia, visual aura (scotomas), and sensory aura (left upper limb paresthesia). Some episodes included transient motor weakness in the same limb (60–240 minutes). Previous ineffective preventive therapy included amitriptyline (25 mg/day), propranolol (40 mg/day), and lamotrigine (150 mg/day). Subsequent flunarizine (5 mg, three times weekly) achieved marked clinical improvement with complete resolution of hemiplegic episodes. Upon planning pregnancy, treatment was discontinued. After initial symptom remission during early gestation, clinical worsening occurred at 12 weeks ‘gestation with daily headaches and hemiplegic aura. Although flunarizine is generally not recommended for migraine treatment during pregnancy, it was reintroduced following a multidisciplinary evaluation with our Teratology Information Service, based on the absence of evidence suggesting an increased baseline risk of congenital malformations. Gradual improvement occurred allowing treatment discontinuation at 20 weeks ‘gestation. The patient delivered a healthy female infant at 37 weeks (APGAR 9/10; birth weight 2650 g, length 45 cm, head circumference 32 cm). No congenital malformations or adverse effects were reported during pregnancy or breastfeeding.

Conclusion: Although flunarizine is generally not recommended during pregnancy due to limited safety data, it may represent a viable therapeutic option in selected cases refractory to other treatments, when safer alternatives are unavailable.