The FDA said Wednesday that it had identified a , mostly in teens and young adults.
In a statement released Wednesday morning, U.S. health officials disclosed that an agency review had identified 35 cases of seizures possibly linked to the use of e-cigarettes from 2010 through early 2019.
"While 35 cases may not seem like much compared to the total number of people using e-cigarettes, we are nonetheless concerned by these reported cases," said FDA Commissioner Scott Gottlieb, MD, and Principal Deputy Commissioner Amy Abernethy, MD, PhD, . "We also recognize that not all of the cases may be reported."
"We want to be clear that we don't yet know if there's a direct relationship between the use of e-cigarettes and a risk of seizure," they noted. "We can't yet say for certain that e-cigarettes are causing these seizures."
However, the "recent uptick" in such cases identified by the agency comes on the heels of multiple studies showing dramatic increases in e-cigarette use, at least hinting at a connection. Nicotine poisoning is known to cause seizures, along with dizziness, nausea, and vomiting and other symptoms. Certain brands of e-cigarettes contain much higher nicotine levels than a typical combustible cigarette, and the vapor isn't as harsh to inhale as smoke -- both of which may make it easier for an individual to overdose.
Some of the 35 incidents were reported to poison control centers and others directly to the FDA.
The agency is asking e-cigarette users to report any "unexpected health or product issues" to the agency through its .
Reports should include information about the specific product used, including brand name; whether the e-cigarette was modified in any way or used with other tobacco products, medications or other substances; and details about the specific health event.
"Additional reports or information about these incidents may help us determine if there's a connection and help identify common risk factors and if any e-cigarette product attributes, such as nicotine content or formulation, may contribute to seizures."
The health officials said the reports made to date do not provide enough information to provide a clear picture of how e-cigarette use is contributing to seizures, if they are contributing at all.
"E-liquids have varying levels of nicotine concentrations, and some e-cigarette design features may allow a user to obtain high levels of nicotine quickly. E-cigarette use behaviors also vary and users may deliberately or inadvertently inhale more nicotine than would typically occur. Additionally, some of the reported incidents may not be directly related to e-cigarette use -- the seizures may have been triggered by an underlying medical condition, use of other substances, or other factors," Gottlieb and Abernethy noted.