The FDA has issued a critical safety warning for Transderm Scōp (scopolamine transdermal system), an anticholinergic patch used to prevent motion sickness and post-operative nausea, following identification of 13 global cases of potentially life-threatening hyperthermia. The warning highlights serious heat-related complications that can occur when the patch impairs the body's natural cooling mechanisms.
Serious Adverse Events Documented Globally
Through August 16, 2024, the FDA identified 13 cases worldwide of hyperthermia associated with scopolamine patches, including seven cases in the United States. The data was compiled from the FDA Adverse Event Reporting System (FAERS) database, biomedical literature, manufacturer-submitted reports, and external regulatory bodies.
Among the 10 cases providing temperature data, three patients experienced maximum body temperatures of 105°F or higher, representing a medical emergency. The remaining seven cases recorded temperatures ranging from 99°F to 104.9°F, with two cases in the lower range (99-100.4°F) and five in the moderate hyperthermia range (100.5-104.9°F).
Vulnerable Populations at Greatest Risk
The demographic analysis reveals concerning patterns in affected populations. Eight cases involved children 17 years or younger, four involved adults 60 years and older, with one case in a young adult. This distribution highlights the particular vulnerability of pediatric and geriatric populations to anticholinergic-induced hyperthermia.
Of the 13 documented cases, 12 resulted in serious outcomes. Six cases led to hospitalization (four patients) or death (two patients). The two fatalities occurred in one child and one older adult patient, both of whom had additional risk factors that may have contributed to hyperthermia development, including concomitant anticholinergic medications or exposure to external heat sources.
Clinical Presentation and Timeline
The temporal relationship between patch application and symptom onset proved consistent across cases. Among eight cases reporting time intervals, all hyperthermia episodes occurred within 72 hours of the most recent patch application. Notably, seven cases developed after the initial application to the patient's body, while one case occurred 18 months after treatment initiation.
The majority of cases (10 out of 13) presented with additional anticholinergic symptoms beyond hyperthermia, including mydriasis (pupil dilation), hallucinations, confusion, disorientation, and urinary retention. These accompanying symptoms reflect the systemic anticholinergic effects of scopolamine absorption.
Off-Label Use Patterns
The reported indications for scopolamine patch use varied significantly from FDA-approved applications. Six cases involved management of drooling or secretions, typically in pediatric patients with neurological conditions, while four cases addressed motion sickness or nausea. Three cases did not specify the reason for use.
Despite lacking FDA approval for pediatric use, the patch is sometimes prescribed off-label for children with neurological conditions who experience excessive drooling or secretions. This practice has contributed to the disproportionate representation of pediatric cases in the adverse event reports.
Regulatory Response and Clinical Recommendations
The FDA now requires updated labeling with enhanced warnings about hyperthermia risk. The agency specifically urges clinicians to exercise heightened caution when prescribing scopolamine patches to high-risk populations, particularly during hot weather conditions when heat-related complications are more likely.
Healthcare providers are advised to counsel patients and caregivers about recognizing early signs of hyperthermia and other anticholinergic effects. Special attention should be paid to vulnerable populations, including children and elderly patients, who may be less able to communicate symptoms or regulate body temperature effectively.
The warning also addresses improper use patterns identified in the case reports, including one case involving simultaneous application of multiple patches and another involving a cut patch, both of which can lead to unpredictable drug absorption and increased risk of adverse effects.
