views updated



Oxazolindinediones are anticonvulsants , indicated for the treatment of absence seizures (sometimes called petit mal seizures) associated with epilepsy and other seizure disorders.


Oxazolindinediones are thought to decrease abnormal activity and excitement within the central nervous system (CNS) that may trigger seizures. While oxazolindinediones is often effective in controlling petit mal seizures associated with epilepsy, there is no known cure for the disorder. If necessary, oxazolindinediones can be used in conjunction with other anti-epileptic drugs (AEDs) that prevent or control other types of seizures.


In the United States, oxazolindinediones are sold under the generic name trimethadione and the brand name Tridione.

Recommended dosage

Oxazolindinediones are taken orally and are available in tablet, chewable tablet, or suspension forms. Oxazolindinediones are appropriate for pediatric and adult patients. Physicians prescribe the medication in varying total daily dosages. Typically, the total daily dosage is administered in three to four divided doses.

When beginning a course of treatment that includes oxazolindinediones, most physicians will prescribe a carefully scheduled dosing regimen. The physician will determine the proper initial dosage, and then gradually raise the patient's daily dosage over the course of several days or weeks until seizure control is achieved. Likewise, dosages are usually tapered down over time when ending treatment with oxazolindinediones.

It is important to not take a double dose of any anti-convulsant medication, including oxazolindinediones. If a daily dose is missed, it should be taken as soon as possible. However, if it is within four hours of the next scheduled dose, then the missed dose should be skipped.


A physician should be consulted before taking oxazolindinediones with certain non-prescription medications. Patients should avoid alcohol and CNS depressants (medicines that can make one drowsy or less alert, such as antihistimines, sleep medications, and some pain medications) while taking oxazolindinediones or any other anticonvulsants, which can exacerbate the side effects of alcohol and other medications.

A course of treatment including oxazolindinediones may not be appropriate for persons with liver or kidney disease, anemia, eye disorders, mental illness, diabetes, high blood pressure, angina (chest pain), irregular heartbeats, or other heart problems. Periodic blood, urine, and liver function tests are advised for many patients (especially pediatric and elderly patients) using the medicine.

Persons taking oxazolindinediones should avoid prolonged exposure to sunlight and should wear protective clothing and sunscreen while outdoors. Oxazolindinediones may make skin sensitive to sunlight and prone to sunburn.

Before beginning treatment with oxazolindinediones, patients should notify their physician if they consume a large amount of alcohol, have a history of drug use, are pregnant, nursing, or plan on becoming pregnant. Anti-convulsant medications may increase the risk of some birth defects. Patients who become pregnant while taking oxazolindinediones should contact their physician.

Side effects

Patients should discuss with their physicians the risks and benefits of treatment with oxazolindinediones before taking the medication. Oxazolindinediones are usually well tolerated. However, in some patients, they may case a variety of usually mild side effects. Dizziness , nausea, and drowsiness are the most frequently reported side effects of anticonvulsants. Possible side effects that do not usually require medical attention, and may diminish with continued use of the medication include:

  • unusual tiredness or weakness
  • loss of appetite
  • weight loss
  • abdominal pain
  • speech problems
  • nausea
  • diarrhea or constipation
  • heartburn or indigestion
  • dry mouth
  • chills, joint aches, and other flu-like symptoms

If any symptoms persist or become too uncomfortable, the prescribing physician should be notified.

Other, uncommon side effects of oxazolindinediones can be serious or could indicate an allergic reaction. Patients who experience any of the following symptoms should contact a physician:

  • purple spots on the skin
  • jaundice (yellowing of the skin and eyes)
  • bruising easily
  • unusual bleeding
  • dark urine, frequent urination, or burning sensation when urinating
  • extreme mood or mental changes
  • shakiness or unsteady walking
  • severe unsteadiness or clumsiness
  • excessive speech or language problems
  • difficulty breathing
  • chest pain
  • faintness or loss of consciousness
  • persistent, severe headaches
  • persistent fever or pain


Oxazolindinediones may have negative interactions with some antacids, heartburn or acid reflux prevention medications, anticoagulants, antihistamines, antidepressants, antibiotics, and monoamine oxidase inhibitors (MAOIs). Oxazolindinediones may be used in conjunction with other seizure prevention medications (anticonvulsants or anti-epileptic drugs) only if advised and monitored by a physician. Many anticonvulsants may decrease the effectiveness of oral contraceptives (birth control pills) or contraceptive injections or implants containing estrogen and progestins.



Devinsky, Orrin, MD. Epilepsy: Patient and Family Guide, 2nd ed. Philadelphia: F. A. Davis Co., 2001.

Weaver, Donald F. Epilepsy and Seizures: Everything You Need to Know. Toronto: Firefly Books, 2001.


"Trimethadione." Medline Plus. National Library of Medicine. May 6, 2004 (May 27, 2004). <http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a601127.html>.

"Trimethdione." Yale New Haven Health Service Drug Guide. May 6, 2004 (May 27, 2004). <http://yalenewhavenhealth.org/Library/HealthGuide/DrugGuide/topic.asp?hwid=multumd00945a1>.


Epilepsy Foundation. 4351 Garden City Drive, Landover, MD 20785-7223. (800) 332-1000. <http://www.epilepsyfoundation.org>.

American Epilepsy Society. 342 North Main Street, West Hartford, CT 06117-2507. <http://www.aesnet.org>.

Adrienne Wilmoth Lerner