Seizures affect up to 10% of adults at some point in their lives, with the risk increasing notably after age 551 . A first-time seizure in adulthood can arise from various causes, ranging from acute medical conditions to chronic brain disorders1 . Understanding these causes and the appropriate responses is essential for timely diagnosis, treatment, and prevention of recurrence2 .
Alcohol Withdrawal
Chronic alcohol use leads to physical dependence and addiction, which significantly increases the risk of withdrawal seizures3 . When a person abruptly stops drinking, the sudden absence of alcohol triggers neuroexcitation, causing withdrawal symptoms that often peak between one and three days after cessation and may last for days to weeks3 . Among these symptoms, seizures are a serious concern and can escalate to delirium tremens, a severe withdrawal syndrome marked by seizures, hallucinations, and profound confusion3 . Management of severe alcohol withdrawal, including delirium tremens, typically requires inpatient medical care to ensure safety and effective treatment3 .
Heat Stroke
Heat stroke is a medical emergency caused by exposure to excessive heat, leading to a rapid rise in core body temperature often exceeding 40°C (104°F) 4. This hyperthermia disrupts normal brain function and can provoke neurological dysfunction, including seizures4 . Symptoms of heat stroke may include seizures, altered mental status, and unconsciousness, necessitating urgent medical intervention to prevent permanent brain damage or death4 .
High Fever
Febrile seizures are seizures associated with fever, most commonly occurring in children under five years old5 . While febrile seizures are rare in adults, fever remains a recognized trigger for seizure activity due to its effect on brain excitability5 . Genetic factors may increase susceptibility to febrile seizures, although the exact mechanisms are not fully understood5 . Risk factors for recurrent febrile seizures include a family history of epilepsy, prior prolonged seizures, and neurological injury or brain damage5 .
Low Blood Sugar
Hypoglycemia, or low blood glucose levels, disrupts brain function and can provoke seizures6 . This metabolic disturbance may also contribute to cerebrovascular events that further increase seizure risk6 . Various conditions can lead to hypoglycemia, including insulin treatment in diabetics, especially after exercise, severe infections such as sepsis even in non-diabetics, and organ failure involving the heart, kidneys, or liver6 . Prompt recognition and correction of hypoglycemia are critical to prevent seizures and associated complications6 .
Medical Issues
Several medical conditions can alter cerebral function and provoke seizures. Stroke is the leading cause of new-onset seizures in the elderly due to ischemic brain injury7 . Electrolyte imbalances, including hyponatremia, hypocalcemia, and hypomagnesemia, disrupt neuronal activity and can trigger seizures3 . Eclampsia, a pregnancy complication associated with preeclampsia, is characterized by seizures3 . Additionally, renal or hepatic failure can cause metabolic disturbances that increase seizure risk3 . Identifying and managing these underlying medical issues is essential in seizure prevention and treatment3 .
Medication Side Effects
Certain medications and toxic substances can induce seizures as adverse effects8 . Approximately 9% of status epilepticus cases are linked to drug toxicity or poisoning8 . Both prescription medications and illicit drugs may provoke seizures, with stimulant drugs such as cocaine and methamphetamine being frequent causes8 . Overdose or toxicity of diphenhydramine, a common antihistamine, can also lead to seizures8 . Patients should be informed about the seizure risks associated with their medications and advised to monitor for symptoms, seeking immediate medical care if severe adverse reactions occur8 .
Traumatic Brain Injury
Traumatic brain injury (TBI) results from external forces causing brain tissue damage, commonly due to falls, sports injuries, or motor vehicle collisions3 . Concussion represents a mild form of TBI3 . Seizures may occur following TBI, with early post-traumatic seizures typically happening within seven days of injury3 . The risk of seizures correlates with injury severity, and severe TBIs may lead to lasting disability or death3 . Post-traumatic epilepsy is a chronic seizure disorder that can develop after brain injury3 . Prompt evaluation within 24 hours after TBI is critical to assess for complications, including seizures3 . Mild TBIs infrequently result in seizures or chronic neurological issues3 .
What to Do During a Seizure
The safety of the person experiencing a seizure is the primary concern during the event3 . Most seizures end spontaneously, so supportive care is essential3 . Key steps include:
- Do not restrain the person to avoid injury3 .
- Position the person in the recovery position to maintain an open airway3 .
- Loosen restrictive clothing and remove glasses to prevent harm3 .
- Protect the head by placing a soft object underneath3 .
- Stay with the individual until they have fully recovered or help arrives3 .
These measures help minimize injury and ensure airway safety during a seizure3 .
When to Call a Healthcare Provider
While not all seizures require emergency care, certain situations demand urgent medical attention3 . Contact a healthcare provider or emergency services if:
- The seizure lasts more than five minutes or multiple seizures occur in close succession3 .
- The person has difficulty breathing or remains unconscious after the seizure3 .
- The seizure causes injury3 .
- The person is pregnant or has significant comorbidities3 .
- The seizure occurs in water, posing a drowning risk3 .
Prompt evaluation after a first seizure is important to identify underlying causes and initiate appropriate treatment3 .
A Quick Review
First-time seizures in adults can be provoked by a variety of causes, including stroke, infections, metabolic disturbances, substance use or withdrawal, and brain injury9 87. The risk of seizure recurrence is highest within the first two years after the initial event, especially in individuals with prior brain insults, epileptiform abnormalities on EEG, significant brain imaging abnormalities, or nocturnal seizures2 10. Immediate initiation of anti-seizure medication reduces recurrence risk in the short term but may not improve long-term outcomes11 10. Safety counseling and avoidance of seizure triggers such as sleep deprivation, alcohol misuse, and stress are essential components of management1 12.
| Cause | Typical Age Group | Mechanism/Notes | Evidence Level |
|---|---|---|---|
| Stroke | Older adults | Ischemic brain injury | High |
| Alcohol withdrawal | Adults | Neuroexcitation during withdrawal | High |
| Traumatic brain injury | All ages | Structural brain damage | High |
| Electrolyte imbalance | All ages | Metabolic disruption of neuronal activity | High |
| Infection (e.g., neurocysticercosis) | All ages, esp. endemic areas | Parasitic CNS infection | High |
| Medication/drugs | All ages | Toxic or idiosyncratic reactions | High |
| Heat stroke | All ages | Hyperthermia-induced brain dysfunction | High |
