Common triggers include flashing lights and sudden noises. In certain types of epilepsy, seizures happen more often during sleep, and in other types they occur almost only when sleeping. Seizure clusters
Patients with epilepsy may experience seizure clusters which may be broadly defined as an acute deterioration in seizure control. The prevalence of seizure clusters is uncertain given that studies have used different definitions to define them. However, estimates suggest that the prevalence may range from 5% to 50% of epilepsy patients. Refractory epilepsy patients who have a high seizure frequency are at the greatest risk for having seizure clusters. Seizure clusters are associated with increased healthcare utilization, worse quality of life, impaired psychosocial functioning, and possibly increased mortality. Benzodiazepines are used as an acute treatment for seizure clusters. Post-ictal
After the active portion of a seizure (the ictal state) there is typically a period of recovery during which there is confusion, referred to as the postictal period, before a normal level of consciousness returns. It usually lasts 3 to 15 minutes but may last for hours. Other common symptoms include feeling tired, headache, difficulty speaking, and abnormal behavior. Psychosis after a seizure is relatively common, occurring in 6–10% of people. Often people do not remember what happened during this time. Localized weakness, known as Todds paralysis, may also occur after a focal seizure. It would typically last for seconds to minutes but may rarely last for a day or two. Psychosocial
Epilepsy can have adverse effects on social and psychological well-being.
Restriction fragment length polymorphism (RFLP) analysis was the first genetic test developed and is still used as of 2020, although it is being phased out by newer methods. It involves dicing the DNA with restriction enzymes and sorting the resulting restriction fragments by size using southern blot. The restriction enzymes EcoRI and BlnI are commonly used. EcoRI isolates the 4q and 10q repeat arrays, and BlnI dices the 10q sequence into small pieces, allowing 4q to be distinguished. The EcoRI restriction fragment is composed of three parts: 1) 5.7 kb proximal part, 2) the central, variable size D4Z4 repeat array, and 3) the distal part, usually 1.25 kb. The proximal portion has a sequence of DNA stainable by the probe p13E-11, which is commonly used to visualize the EcoRI fragment during southern blot. The name "p13E-11" reflects that it is a subclone of a DNA sequence designated as cosmid 13E during the human genome project. Considering that each D4Z4 repeat is 3.3 kb, and the EcoRI fragment contains 6.9 kb of DNA that is not part of the D4Z4 repeat array, the number of D4Z4 units can be calculated. D4Z4 repeats = (EcoRI length - 6.9) / 3.3Sometimes 4q or 10q will have a combination of D4Z4 and D4Z4-like repeats due to DNA exchange between 4q and 10q, which can yield erroneous results, requiring more detailed workup. Sometimes D4Z4 repeat array deletions can include the p13E-11 binding site, warranting use of alternate probes.