[12] People with epilepsy may be treated differently in various areas of the world and experience varying degrees of social stigma due to the alarming nature of their symptoms.

[11] The underlying mechanism of an epileptic seizure is excessive and abnormal neuronal activity in the cortex of the brain,[12] which can be observed in the electroencephalogram (EEG) of an individual.

[28] The seizures can include sensory (visual, hearing, or smell), psychic, autonomic, and motor phenomena depending on which part of the brain is involved.

[33] Absence seizures can be subtle with only a slight turn of the head or eye blinking with impaired consciousness;[2] typically, the person does not fall over and returns to normal right after it ends.

[29] Rarer seizure types can cause involuntary unnatural laughter (gelastic), crying (dyscrastic), or more complex experiences such as déjà vu.

[74][75] These mutations result in the upregulation of the mechanistic target of rapamycin (mTOR) pathway which leads to the growth of tumors in many organs including the brain, skin, heart, eyes and kidneys.

Clinical manifestations are variable but may include hyperpigmented skin marks, hamartomas of the iris called Lisch nodules, neurofibromas, optic pathway gliomas and cognitive impairment.

[91][92] A form of an infection with the pork tapeworm (cysticercosis), in the brain, is known as neurocysticercosis, and is the cause of up to half of epilepsy cases in areas of the world where the parasite is common.

[119] More recent exome and genome sequencing studies have begun to reveal a number of de novo gene mutations that are responsible for some epileptic encephalopathies, including CHD2 and SYNGAP1[120][121][122] and DNM1, GABBR2, FASN and RYR3.

[31] After brain injuries, there is a limited window of time to intervene with treatments to prevent epilepsy, similar to the therapeutic approach used in stroke therapy.

[19] Yoga-based Nadi Shodhana Pranayama, also known as Alternate Nostril Breathing, may positively impact the nervous system and help manage seizure disorders.

Regular exercise helps balance brain function by providing the body with oxygen and removing carbon dioxide and toxins from the blood.

[145] Putting fingers, a bite block or tongue depressor in the mouth is not recommended as it might make the person vomit or result in the rescuer being bitten.

[152][153] In the United Kingdom, carbamazepine or lamotrigine are recommended as first-line treatment for focal seizures, with levetiracetam and valproate as second-line due to issues of cost and side effects.

[106] Many of the common used medications, such as valproate, phenytoin, carbamazepine, phenobarbital, and gabapentin have been reported to cause increased risk of birth defects,[158] especially when used during the first trimester.

[16] Results from a 2023 systematic review found that surgical interventions for children aged 1–36 months with drug-resistant epilepsy can lead to significant seizure reduction or freedom, especially when other treatments have failed.

[164][162] Neurostimulation via neuro-cybernetic prosthesis implantation may be another option in those who are not candidates for surgery, providing chronic, pulsatile electrical stimulation of specific nerve or brain regions, alongside standard care.

[167] In a 2022 Cochrane review of four randomized controlled trials, with moderate certainty of evidence, people receiving h-VNS treatment were 73% more likely (13% more likely to 164% more likely) to experience a reduction in seizure frequency by at least 50% (the minimum threshold defined for individual clinical response).

[188] Planning pregnancies in advance gives women with epilepsy an opportunity to switch to a lower-risk treatment program and reduced drug doses.

[195] Mortality is often related to the underlying cause of the seizures, status epilepticus, suicide, trauma, and sudden unexpected death in epilepsy (SUDEP).

[196] SUDEP appears to be partly related to the frequency of generalized tonic-clonic seizures[198] and accounts for about 15% of epilepsy-related deaths;[192] it is unclear how to decrease its risk.

[19] In the developing world its onset is more common in older children and young adults due to the higher rates of trauma and infectious diseases.

[204] As the Babylonians had no biomedical understanding of the nature of epilepsy, they attributed the seizures to possession by evil spirits and called for treating the condition through spiritual means.

[24] Hippocrates proposed that heredity was important as a cause, described worse outcomes if the condition presents at an early age, and made note of the physical characteristics as well as the social shame associated with it.

As late as in the second half of the 20th century, in Tanzania and other parts of Africa epilepsy was associated with possession by evil spirits, witchcraft, or poisoning and was believed by many to be contagious.

[19] In parts of Africa, such as Tanzania and Uganda, epilepsy is claimed to be associated with possession by evil spirits, witchcraft, or poisoning and is incorrectly believed by many to be contagious.

[31] In the United States, the Epilepsy Foundation is a national organization that works to increase the acceptance of those with the disorder, their ability to function in society and to promote research for a cure.

[234] Because epileptic seizures of different kinds are observed naturally in some of these animals, strains of mice and rats have been selected to be used as genetic models of epilepsy.

Some foals eventually outgrow the condition without significant long-term effects, while others may face severe consequences, including death or lifelong complications, if left untreated.

Earlier research has pointed to a significant genetic influence in the development of JIE, suggesting that the condition may follow the inheritance pattern of a single-gene trait.