eMedicine Specialties > Neurology > Seizures and Epilepsy

Absence Seizures: Follow-up

Author: Scott Segan, MD, Director of SBH Stroke Center and Attending Neurologist, St Barnabas Hospital
Contributor Information and Disclosures

Updated: Apr 7, 2009

Follow-up

Further Outpatient Care

  • Children with absence seizures should be monitored closely during titration or crossover of AEDs. The dose of the medication should be increased weekly until seizures are controlled or adverse effects develop.
  • The aim in therapy is to control seizures completely with the minimum required amount of medication to minimize adverse effects.
  • The therapeutic effect of valproic acid for absence seizures may lag several weeks behind reaching a therapeutic level.51
  • Liver function test, amylase and/or lipase, and CBC results should be monitored during drug treatment to watch for adverse reactions.
  • Drug levels should be monitored to ensure compliance and to watch for toxic levels in patients who are too young or too developmentally disabled to articulate subjective adverse effects.

Complications

Absence status epilepticus may occur spontaneously, as a result of a concurrent illness, or after the administration of a drug that lowers the seizure threshold.

  • On clinical evaluation, the patient appears to be in a dreamy state with partial responsiveness and automatisms; at times the presentation may be more subtle, with only mild encephalopathy. The diagnosis is made by EEG confirmation of generalized 3-Hz spike-and-wave complexes, although the discharges may be slower and less regular than with isolated seizures.
  • Treatment has been intravenous benzodiazepines. In some patients, this may be replaced by or supplemented with intravenous valproic acid because intravenous benzodiazepines have been reported to produce tonic status in patients with symptomatic generalized epilepsy.52

Prognosis

  • The prognosis for the primary generalized epilepsies depends on the particular epileptic syndrome. Because seizures, particularly generalized tonic-clonic seizures, may occur well after patients appear to achieve good control, a long seizure-free period should be achieved before discontinuation of therapy is considered.
  • The remission rate for childhood absence epilepsy is good; 80% respond to medication. Complete remission rates vary widely, perhaps dependent on the length of follow-up. 
    • Generalized tonic-clonic seizures may develop in up to 40% of children with childhood absence epilepsy.27
    • Persistence of seizures is more likely in those with generalized tonic-clonic seizures.
    • Early onset of absence seizures, quick response to therapy53 , and normal EEG background are good prognostic signs.
  • Juvenile myoclonic epilepsy carries a high risk of generalized tonic-clonic seizures.
    • Despite excellent control with relatively small doses of an AED, the relapse rate is greater than 90%.54
    • Patients with juvenile myoclonic epilepsy generally need to be treated for life, though occasional patients achieve control with careful attention to lifestyle issues (eg, adequate sleep, abstinence from alcohol).

Patient Education

For excellent patient education resources, visit eMedicine's Brain and Nervous System Center. Also, see eMedicine's patient education article Epilepsy.

Miscellaneous

Medicolegal Pitfalls

  • The 2 main pitfalls in treatment of absence seizures both involve incorrect diagnosis.
    • On occasion, a patient without epilepsy is identified as having epilepsy.
    • Staring spells, daydreaming, migraine equivalents, and panic and/or anxiety attacks all may be confused with nonconvulsive seizures.
  • Certain epileptic syndromes are often undiagnosed or misdiagnosed.
    • Patients who present with a generalized tonic-clonic seizure are often given an AED without efficacy against absence or myoclonic seizures. Their generalized tonic-clonic seizures may be controlled, but they may have unrecognized absence or myoclonic seizures.
    • Patients with absence seizures may be identified as having complex partial seizures, and vice versa. This leads to incorrect treatment and an inaccurate understanding of the prognosis.
  • Careful history taking and EEG studies can help avoid these pitfalls.

Special Concerns

  • Patients who are old enough to drive should be warned about driving and operating heavy machinery. Physicians should be familiar with state laws concerning driving with epilepsy; inform patients concerning these legal matters.
  • Women of childbearing age who are not using adequate birth control should not be treated with valproic acid, if equally effective alternatives are available for them.
    • If a woman taking valproic acid wishes to become pregnant, treatment may be crossed over to ethosuximide if only absence seizures are present, and she may be given folic acid 1-5 mg/d before conception. After the first trimester, treatment may be switched back to valproic acid.
    • Women with generalized tonic-clonic seizures may be crossed over to lamotrigine, and given folic acid 1-5 mg/d before conception.
    • Most clinicians believe that women treated with valproic acid or any hepatic enzyme-inducing AED should be treated with vitamin K before delivery.
 


More on Absence Seizures

Overview: Absence Seizures
Differential Diagnoses & Workup: Absence Seizures
Treatment & Medication: Absence Seizures
Follow-up: Absence Seizures
Multimedia: Absence Seizures
References
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References

  1. Proposal for revised clinical and electroencephalographic classification of epileptic seizures. From the Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. Aug 1981;22(4):489-501. [Medline].

  2. Blumenfeld H. From molecules to networks: cortical/subcortical interactions in the pathophysiology of idiopathic generalized epilepsy. Epilepsia. 2003;44 Suppl 2:7-15. [Medline].

  3. Temkin O. The Falling Sickness. Johns Hopkins Press: Baltimore, MD; 1971:250.

  4. Gibbs FA, Davis H, Lennox WG. The EEG in epilepsy and in conditions of impaired consciousness. Arch Neurol Psychiat. 1935;34:1134-48.

  5. Proposal for revised classification of epilepsies and epileptic syndromes. Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia. Jul-Aug 1989;30(4):389-99. [Medline].

  6. Benbadis SR, Berkovic SF. Absence Seizures. In: Wyllie E, Gupta A and Lachhwani DK. The Treatment of Epilepsy. Principles and Practice. 4th ed. Philadelphia: Lippincott, Williams and Wilkins; 2006:305-315.

  7. Panayiotopoulos CP. Typical Absence Seizures. The International League Against Epilepsy. Available at http://www.ilae-epilepsy.org/Visitors/Centre/ctf/typical_absence.cfm. Accessed March 16, 2008.

  8. Dulac O. Atypical Absence. The International League Against Epilepsy. Available at http://www.ilae-epilepsy.org/Visitors/Centre/ctf/atypical_absence.cfm. Accessed March 16, 2008.

  9. Lennox WG, Lennox MA. Epilepsy and Related Disorders. Boston: Little, Brown; 1960:548-574.

  10. Rudolf G, Thérèse Bihoreau M, F Godfrey R, P Wilder S, D Cox R, Lathrop M, et al. Polygenic control of idiopathic generalized epilepsy phenotypes in the genetic absence rats from Strasbourg (GAERS). Epilepsia. Apr 2004;45(4):301-8. [Medline].

  11. Noebles JL, Fariello RG, Jobe PC, Lasley SN and Marescaux C. Genetic models of generalized epilepsy. In: Engel J Jr, Pedley TA. Epilepsy: A Comprehensive Textbook. Philadelphia, PA: Lippincott-Raven; 1997:2327-46.

  12. Benbadis SR. Practical management issues for idiopathic generalized epilepsies. Epilepsia. 2005;46 Suppl 9:125-32. [Medline].

  13. Greenberg DA, Delgado-Escueta AV, Widelitz H, Sparkes RS, Treiman L, Maldonado HM, et al. Juvenile myoclonic epilepsy (JME) may be linked to the BF and HLA loci on human chromosome 6. Am J Med Genet. Sep 1988;31(1):185-92. [Medline].

  14. Liu AW, Delgado-Escueta AV, Gee MN, Serratosa JM, Zhang QW, Alonso ME, et al. Juvenile myoclonic epilepsy in chromosome 6p12-p11: locus heterogeneity and recombinations. Am J Med Genet. Jun 14 1996;63(3):438-46. [Medline].

  15. Bai D, Alonso ME, Medina MT, Bailey JN, Morita R, Cordova S, et al. Juvenile myoclonic epilepsy: linkage to chromosome 6p12 in Mexico families. Am J Med Genet. Dec 1 2002;113(3):268-74. [Medline].

  16. Stogmann E, Lichtner P, Baumgartner C, Bonelli S, Assem-Hilger E, Leutmezer F, et al. Idiopathic generalized epilepsy phenotypes associated with different EFHC1 mutations. Neurology. Dec 12 2006;67(11):2029-31. [Medline].

  17. Suzuki T, Delgado-Escueta AV, Aguan K, Alonso ME, Shi J, Hara Y, et al. Mutations in EFHC1 cause juvenile myoclonic epilepsy. Nat Genet. Aug 2004;36(8):842-9. [Medline].

  18. Annesi F, Gambardella A, Michelucci R, Bianchi A, Marini C, Canevini MP. Mutational analysis of EFHC1 gene in Italian families with juvenile myoclonic epilepsy. Epilepsia. Sep 2007;48(9):1686-90. [Medline].

  19. Pinto D, Louwaars S, Westland B, Volkers L, de Haan GJ, Trenité DG, et al. Heterogeneity at the JME 6p11-12 locus: absence of mutations in the EFHC1 gene in linked Dutch families. Epilepsia. Oct 2006;47(10):1743-6. [Medline].

  20. Fong GC, Shah PU, Gee MN, Serratosa JM, Castroviejo IP, Khan S, et al. Childhood absence epilepsy with tonic-clonic seizures and electroencephalogram 3-4-Hz spike and multispike-slow wave complexes: linkage to chromosome 8q24. Am J Hum Genet. Oct 1998;63(4):1117-29. [Medline].

  21. Wallace RH, Marini C, Petrou S, Harkin LA, Bowser DN, Panchal RG, et al. Mutant GABA(A) receptor gamma2-subunit in childhood absence epilepsy and febrile seizures. Nat Genet. May 2001;28(1):49-52. [Medline].

  22. Tanaka M, Olsen RW, Medina MT, Schwartz E, Alonso ME, Duron RM. Hyperglycosylation and reduced GABA currents of mutated GABRB3 polypeptide in remitting childhood absence epilepsy. Am J Hum Genet. Jun 2008;82(6):1249-61. [Medline].

  23. Jasper HH, Droogleever-Fortuyn J. Experimental studies on the functional anatomy of petit mal epilepsy. Assoc Res Nerv Ment Dis. 1947;26:272-98.

  24. Williams, D. A study of thalamic and cortical rhythms in petit mal. Brain. 1953;76:50-69.

  25. Gloor P, Quesney LF, Zumstein H. Pathophysiology of generalized penicillin epilepsy in the cat: the role of cortical and subcortical structures. II. Topical application of penicillin to the cerebral cortex and to subcortical structures. Electroencephalogr Clin Neurophysiol. Jul 1977;43(1):79-94. [Medline].

  26. Panayiotopoulos CP. Absence epilepsies. In: Engel J Jr, Pedley TA, eds. Epilepsy: A Comprehensive Textbook. Philadelphia, PA: Lippincott-Raven; 1997:2327-46.

  27. Loiseau P. Childhood absence epilepsy. In: Roger J, Bureau M, Dravet, et al, eds. Epileptic Syndromes. London, England: John Libby; 1985: 106-20.

  28. Tassinari CA, Bureau M. Epilepsy with myoclonic absences. In: Roger J, Bureau M, Dravet, et al, eds. Epileptic Syndromes. London, England: John Libby; 1985:121-9.

  29. Beaumanoir A. Roger J, Bureau M, Dravet, et al, eds. Epileptic Syndromes. London, England: John Libby; 1985:11: 89-99.

  30. Wolf P. Juvenile absence epilepsy. In: Roger J, Bureau M, Dravet, et al, eds. Epileptic Syndromes. London, England: John Libby; 1985:242-6.

  31. Wolf P. Juvenile myoclonic epilepsy. In: Roger J, Bureau M, Dravet, et al, eds. Epileptic Syndromes. London, England: John Libby; 1985:247-58.

  32. Dreifuss FE. Classification of epileptic seizures. In: Engel J Jr, Pedley TA, eds. Epilepsy: A Comprehensive Textbook. Philadelphia, PA: Lippincott-Raven;1997.

  33. Penry JK, Porter RJ, Dreifuss RE. Simultaneous recording of absence seizures with video tape and electroencephalography. A study of 374 seizures in 48 patients. Brain. Sep 1975;98(3):427-40. [Medline].

  34. Panayiotopoulos CP. Idiopathic generalized epilepsies: a review and modern approach. Epilepsia. 2005;46 Suppl 9:1-6. [Medline].

  35. Betting LE, Mory SB, Lopes-Cendes I, Li LM, Guerreiro MM, Guerreiro CA, et al. MRI reveals structural abnormalities in patients with idiopathic generalized epilepsy. Neurology. Sep 12 2006;67(5):848-52. [Medline].

  36. Sadleir LG, Farrell K, Smith S, Connolly MB, Scheffer IE. Electroclinical features of absence seizures in childhood absence epilepsy. Neurology. Aug 8 2006;67(3):413-8. [Medline].

  37. Browne TR, Penry JK, Proter RJ, Dreifuss FE. Responsiveness before, during, and after spike-wave paroxysms. Neurology. Jul 1974;24(7):659-65. [Medline].

  38. Lerman P. Seizures induced or aggravated by anticonvulsants. Epilepsia. Nov-Dec 1986;27(6):706-10. [Medline].

  39. Snead OC 3rd, Hosey LC. Exacerbation of seizures in children by carbamazepine. N Engl J Med. Oct 10 1985;313(15):916-21. [Medline].

  40. Liu L, Zheng T, Morris MJ, Wallengren C, Clarke AL, Reid CA, et al. The mechanism of carbamazepine aggravation of absence seizures. J Pharmacol Exp Ther. Nov 2006;319(2):790-8. [Medline].

  41. Vendrame M, Khurana DS, Cruz M, Melvin J, Valencia I, Legido A, et al. Aggravation of seizures and/or EEG features in children treated with oxcarbazepine monotherapy. Epilepsia. Nov 2007;48(11):2116-20. [Medline].

  42. Guerrini R, Belmonte A, Genton P. Antiepileptic drug-induced worsening of seizures in children. Epilepsia. 1998;39 Suppl 3:S2-10. [Medline].

  43. Skodda S, Kramer I, Spittler JF, Gehlen W. Non-convulsive status epilepticus in two patients receiving tiagabine add-on treatment. J Neurol. Feb 2001;248(2):109-12. [Medline].

  44. Perucca E. The management of refractory idiopathic epilepsies. Epilepsia. 2001;42 Suppl 3:31-5. [Medline].

  45. Hemingway C, Freeman JM, Pillas DJ, Pyzik PL. The ketogenic diet: a 3- to 6-year follow-up of 150 children enrolled prospectively. Pediatrics. Oct 2001;108(4):898-905. [Medline].

  46. Edwards, N. The MCT Diet. epilepsy.com. Available at http://www.epilepsy.com/epilepsy/keto_news_august07. Accessed 3/15/09.

  47. Lefevre F, Aronson N. Ketogenic diet for the treatment of refractory epilepsy in children: A systematic review of efficacy. Pediatrics. Apr 2000;105(4):E46. [Medline].

  48. Berkovic SF, Knowlton RC, Leroy RF, Schiemann J, Falter U. Placebo-controlled study of levetiracetam in idiopathic generalized epilepsy. Neurology. Oct 30 2007;69(18):1751-60. [Medline].

  49. Coppola G, Auricchio G, Federico R, Carotenuto M, Pascotto A. Lamotrigine versus valproic acid as first-line monotherapy in newly diagnosed typical absence seizures: an open-label, randomized, parallel-group study. Epilepsia. Sep 2004;45(9):1049-53. [Medline].

  50. Posner EB, Mohamed K, Marson AG. Ethosuximide, sodium valproate or lamotrigine for absence seizures in children and adolescents. Cochrane Database Syst Rev. 2005;(4):CD003032. [Medline].

  51. Wheeler MM, Winter ME. Valproic Acid. In: Winter ME. Basic Clinical Pharmacokinetics. 4. Philadelphia: Lippincott Williams & Wilkins; 2003:438/14.

  52. Tassinari CA, Dravet C, Roger J, Cano JP, Gastaut H. Tonic status epilepticus precipitated by intravenous benzodiazepine in five patients with Lennox-Gastaut syndrome. Epilepsia. Jul 1972;13(3):421-35. [Medline].

  53. Wirrell E, Camfield C, Camfield P, Dooley J. Prognostic significance of failure of the initial antiepileptic drug in children with absence epilepsy. Epilepsia. Jun 2001;42(6):760-3. [Medline].

  54. Delgado-Escueta AV, Enrile-Bacsal F. Juvenile myoclonic epilepsy of Janz. Neurology. Mar 1984;34(3):285-94. [Medline].

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Further Reading

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Keywords

absence seizure, petit mal seizures, generalized seizures, idiopathic generalized epilepsy, symptomatic generalized epilepsy, seizure treatment, epilepsy treatment, idiopathic generalized epilepsies, childhood absence epilepsy, pyknolepsy, juvenile absence epilepsy, juvenile myoclonic epilepsy, impulsive petit mal seizures, typical absence seizures, symptomatic generalized epilepsies, nonpyknoleptic seizures, spanioleptic absence seizures

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Contributor Information and Disclosures

Author

Scott Segan, MD, Director of SBH Stroke Center and Attending Neurologist, St Barnabas Hospital
Scott Segan, MD is a member of the following medical societies: American Academy of Neurology and American Epilepsy Society
Disclosure: UCB Pharma Honoraria Speaking and teaching

Medical Editor

Edward B Bromfield, MD, Associate Professor of Neurology, Faculty Member, Division of Sleep Medicine, Harvard Medical School; Chief, Division of EEG, Epilepsy and Sleep Neurology, Consulting Neurologist, Brigham and Women's Hospital
Edward B Bromfield, MD is a member of the following medical societies: American Academy of Neurology, American Clinical Neurophysiology Society, American Epilepsy Society, American Neurological Association, and Massachusetts Medical Society
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Jose E Cavazos, MD, PhD, FAAN, Associate Professor with Tenure, Departments of Neurology, Pharmacology, and Physiology, University of Texas Health Science Center at San Antonio; Co-Director, South Texas Comprehensive Epilepsy Center; Director of the Epilepsy Center, Audie L Murphy Veterans Affairs Medical Center
Jose E Cavazos, MD, PhD, FAAN is a member of the following medical societies: American Academy of Neurology, American Clinical Neurophysiology Society, American Epilepsy Society, and Society for Neuroscience
Disclosure: Nothing to disclose.

CME Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

 
 
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