From the Guidelines
Delirium and seizures are distinct neurological conditions with different presentations and causes, and accurate diagnosis is crucial to provide appropriate treatment and improve patient outcomes. Delirium is a disturbance in mental state characterized by confusion, disorientation, altered consciousness, and fluctuating attention that develops over hours to days, often caused by underlying medical conditions like infections, medications, or metabolic disturbances affecting brain function over time 1. In contrast, seizures or convulsions are sudden, abnormal electrical discharges in the brain that cause temporary changes in behavior, movement, sensation, or consciousness, typically lasting seconds to minutes and may involve jerking movements, loss of consciousness, or staring spells depending on the type 1.
Some key differences between delirium and seizures include:
- Delirium is a fluctuating disturbance in mental state, while seizures are brief electrical events
- Delirium often presents with hallucinations, agitation, and disrupted sleep-wake cycles, while seizures may involve jerking movements, loss of consciousness, or staring spells
- Delirium results from underlying medical conditions, while seizures may be caused by epilepsy, brain injury, or acute triggers
Treatment approaches differ significantly:
- Delirium management focuses on addressing underlying causes and providing supportive care with medications like haloperidol or quetiapine if needed 1
- Seizures are typically managed with anticonvulsant medications such as levetiracetam, valproate, or phenytoin 1
The distinction between delirium and seizures matters because misdiagnosis could lead to inappropriate treatment and delayed resolution of symptoms, highlighting the importance of accurate diagnosis and treatment to improve patient outcomes and reduce morbidity and mortality 1.
From the FDA Drug Label
Serum levels of phenytoin sustained above the optimal range may produce confusional states referred to as "delirium," "psychosis," or "encephalopathy," or rarely irreversible cerebellar dysfunction. Serum levels of phenytoin (the active metabolite of fosphenytoin sodium injection) sustained above the therapeutic range may produce confusional states referred to as “delirium,” “psychosis,” or “encephalopathy,” or rarely, irreversible cerebellar dysfunction and/or cerebellar atrophy
Delirium is characterized by confusional states, psychosis, or encephalopathy, which can occur when serum levels of phenytoin are sustained above the optimal range. Convulsion or seizure, on the other hand, is not directly described in the provided text as a condition that can be differentiated from delirium based on the information given. Therefore, a conservative clinical decision would be to monitor serum levels of phenytoin and adjust the dosage accordingly to prevent delirium, but the provided text does not offer a clear differentiation between delirium and convulsion or seizure. 2 3
From the Research
Differentiation between Delirium and Convulsion or Seizure
The key differences between delirium and convulsion or seizure are outlined below:
- Definition and Cause: Delirium is an acute confusional state, a manifestation of acute encephalopathy, often caused by toxic, metabolic, or infectious factors 4, 5. In contrast, convulsion or seizure is a condition of spontaneous, recurrent paroxysmal electrical excitation or dysfunction, often involving the acute interruption of brain function 5, 6.
- Clinical Features: Delirium is characterized by subacute changes in cognition, awareness, and activity levels, behavioral disturbance, clouding consciousness, and sleep-wake cycle changes 5, 7. Seizures, on the other hand, involve the acute interruption of brain function, often with convulsive activity, falls, and injury 5, 6.
- Diagnosis: Electroencephalography (EEG) remains the diagnostic test of choice for differentiating between delirium and seizure, enabling distinctly different treatments 5.
- Treatment: Delirium management involves a multicomponent, primarily nonpharmacologic intervention, focusing on addressing contributing factors and preventing further episodes 4, 7. Seizure management, in contrast, often involves the use of antiepileptic drugs and emergency medical evaluation for seizure- and epilepsy-related emergencies 6.
- Similarities and Overlap: Nonconvulsive epileptic states can present with clinical features resembling delirium, making diagnosis challenging 5. A careful evaluation of predisposing and precipitating factors is essential for accurate diagnosis and effective management of both conditions 7.