By: Annemarie DeChellis
What are Gelastic and Dacrystic seizures?
Gelastic and Dacrystic seizures are rare types of focal or partial seizures (Kerrigan &
Iyengar, 2017). The term Gelastic seizures comes from the Greek word, gelastikos, meaning
laughter, and are characterized by brief involuntary episodes of laughter (Daly & Mulder, 1957).
Similarly, Dacrystic seizures are named after the Greek word dakryon, meaning tear, and are
characterized by involuntary bouts of crying (Offen et al., 1976). Both Gelastic and Dacrystic
seizures typically begin during infancy and persist into adulthood (Berkovic et al., 2003;
Kerrigan & Iyengar, 2017; Lopez-Lao et al., 2007). On average, less than 1% of patients
admitted to EEG monitoring report Gelastic and/or Dacrystic seizures (Blumberg et al., 2012;
Kovac et al., 2015).
Gelastic seizures involve uncontrollable laughter, giggling, and smiling. In addition,
automatic, sympathetic symptoms such as facial flushing, increased blood pressure and heart
rate, and changes in respiratory activity are common (Kerrigan & Iyengar, 2017; Striano et al.,
2005). One patient experiencing Gelastic seizures described them as “pressure to laugh” (Sturm,
Andermann, & Berkovic, 2000). Dacrystic seizures are characterized by stereotyped crying,
which includes lacrimation (tears), sad facial expression, and sobbing. The subjective feeling of
sadness is occasionally felt as well (International League Against Epilepsy, 2020; Tatum et al.,
Other types of seizures such as partial or generalized tonic clonic seizures may occur
alongside Gelastic and Dacrystic seizures (Berkovic et al., 2003; Blumberg et al., 2012; Straino
et al., 2005. Disturbances in cognition and behavior, such as increased aggression, have been
associated with severe cases, but are not common among less severe cases (Striano et al., 2005).
In addition, the early onset of puberty, referred to as precocious puberty, is common among
children when a hypothalamic hamartoma is present (Hope for Hypothalamic Hamartomas,
Hypothalamic hamartomas are the most common cause associated with Gelastic and
Dacrystic seizures. A hypothalamic hamartoma is a benign tumor or lesion of the hypothalamus
(Blumberg et al., 2012; Cedar Sinai, 2021; Kerrigan & Iyengar, 2017; Striano et al., 2005). Other
seizures, such as focal onset impaired awareness seizures, are very common when a
hypothalamic hamartoma is present (Blumberg et al, 2012; Striano et al., 2005). Additionally,
whenever Gelastic and Dacrystic seizures occur together, the cause is most likely to be a
hypothalamic hamartoma. However, when Dacrystic seizures occur without Gelastic seizures a
cortical lesion, typically of the temporal region, is often found (Blumberg et al., 2012). Finally,
there are some reports that Gelastic seizures can be triggered by loud noises, excitement, anxiety,
and fearful responses (Kerrigan & Iyengar, 2017; Cedar Sinai, 2021).
Diagnoses and Treatment
Although the onset of Gelastic and Dacrystic seizures is during infancy, the diagnosis
may not be made until years later due to the subtle symptoms, misattribution to typical infant
behavior, and difficultly diagnosing (Berkovic et al., 2003; Cedar Sinai, 2021; Hope for
Hypothalamic Hamartomas, 2021; Kerrigan & Iyengar, 2017). Electroencephalographic tests
(EEG) can determine if someone is experiencing Gelastic and/or Dacrystic seizures by a patient’s
electoral activity in the brain. Interestingly, Gelastic and Darcystic seizures show similar EEG
patterns (Kahane et al., 1999). Furthermore, MRIs and CT scans can reveal tumors or masses in
the brain that may be contributing to the seizures (Cedar Sinai, 2021).
Treatment is difficult as Gelastic and Dacrystic seizures are typically resistant to
medication (Berkovic et al., 2003; Blumberg et al., 2012; Kerrigan & Iyengar, 2017). However,
seizure medicine can be successful for secondary seizures associated with hypothalamic
hamartomas (Hope for Hypothalamic Hamartomas, 2021). Other treatment options include
surgery and laser or thermal ablation to address tumors or masses causing the seizures (Berkovic
et al., 2003; Cedar Sinai, 2021; Hope for Hypothalamic Hamartomas, 2021). While more
research is needed to determine the outcome for surgical treatment, Berkovic et al., 2012
reported that a transcallosal approach to remove tumors associated with Gelastic seizures seems
the most promising. Gelastic seizures ceased immediately, positive behavior changes were
reported, and after one year about 90% of patients were seizure free.
Gelastic and Darcystic seizures are rare types of partial seizures characterized by brief
episodes of laughing or crying. These types of seizures are often caused by hypothalamic
harmatomas. Although Gelastic and Darcystic seizures are typically medication resistant, seizure
medication can help treat other seizures that occur alongside Gelastic and/or Darcystic seizures.
Another treatment option is surgical removal or laser ablation to remove tumors or masses
causing Gelastic or Darcystic seizures.
If someone is experiencing a seizure it is important to stay by that person and offer
support. People remain conscious and are aware of their surroundings when having a Gelastic or
Darcystic seizure. Therefore, they may become anxious or self-conscious about what other
people think if they have a seizure in public. Educating others and doing what you can to support
a person having Gelastic or Dacrystic seizures can help put the person at ease.
Blumberg, J., Fernández, I. S., Vendrame, M., Oehl, B., Tatum, W. O., Schuele, S., Alexopoulos,
A. V., Poduri, A., Kellinghaus, C., Schulze-Bonhage, A., & Loddenkemper, T. (2012).
Dacrystic seizures: demographic, semiologic, and etiologic insights from a multicenter
study in long-term video-EEG monitoring units. Epilepsia, 53(10), 1810–1819.
Berkovic, S. F., Arzimanoglou, A., Kuzniecky, R., Harvey, A. S., Palmini, A., & Andermann, F.
(2003). Hypothalamic hamartoma and seizures: a treatable epileptic encephalopathy.
Epilepsia, 44(7), 969–973.
Cedar Sinai (2021). Gelastic seizures. Cedar Sinai. Retrieved from: https://www.cedarssinai.org/health-library/diseases-and-conditions/g/gelastic-seizures.html
Daly, D.D., & Mulder, D.W. (1957). Gelastic epilepsy. Neurology, 7(3), 189–192.
Hope for Hypothalamic Hamartomas (2021). Identify the symptoms. Hope for Hypothalamic
Hamartomas. Retrieved from: https://www.hopeforhh.org/identify-the-symptoms/
International League Against Epilepsy (2020). Emotional seizure. International League Against
Epilepsy. Retrieved from: https://www.epilepsydiagnosis.org/seizure/emotionaloverview.html
Kahane, P., Di Leo, M., Hoffmann, D., & Munari, C., (1999). Ictal bradycardia in a patient with a
hypothalamic hamartoma: a stereo-EEG study. Epilepsia, 40, 522-527.
Kerrigan, J. F., & Iyengar, S. (2017). Gelastic and Dacrystic Seizures. Epilepsy Foundation.
Retrieved from: https://www.epilepsy.com/learn/types-seizures/gelastic-and-dacrysticseizures
Kovac, S., Diehl, B., Wehner, T., Fois, C., Toms, N., Walker, M.C. and Duncan, J.S. (2015),
Gelastic seizures: Incidence, clinical and EEG features in adult patients undergoing
video-EEG telemetry. Epilepsia, 56(1), e1-e5.
López-Laso, E., Mateos González, M. E., Camino León, R., Jiménez González, M. D., &
Esparza Rodríguez, J. (2007). Giant hypothalamic hamartoma and dacrystic seizures.
Epileptic Disord, 9(1), 90–93.
Offen, M.L., Davidoff, R.A., Troost, B.T., & Richey, E.T., (1976). Dacrystic Epilepsy. Journal of
Neurology, Neurosurgery, and Psychiatry, 39, 829-834.
Striano, S., Striano, P., Sarappa, C., & Boccella, P. (2005). The clinical spectrum and natural
history of gelastic epilepsy-hypothalamic hamartoma syndrome. Seizure, 14(4), 232-239.
Sturm JW, Andermann F, & Berkovic SF. (2000) Pressure to laugh: an unusual epileptic
syndrome associated with small hypothalamic hamartomas. Neurology, 54, 971-973.
Tatum IV, W. O., Kaplan, P. W., & Jallon, P. (2009). Dacrystic Seizures. Epilepsy A to Z: A
Concise Encyclopedia, 91.