Epilepsy Information

Catamenial epilepsy (hormone sensitive seizures)

Catamenial epilepsy (hormone sensitive seizures)

• This is a term that is used for a type of epilepsy where seizures tend to cluster at certain times of the menstrual cycle.  Catamenial epilepsy may occur with any type of seizures.

• It is estimated that about one third of women with epilepsy may have catamenial epilepsy. While the causes of catamenial epilepsy are not well understood, we do understand that menstrual periods do not cause seizures.  But, some possible explanations may include:
  - Fluctuations in the levels of reproductive hormones (estrogen and progesterone)
  - Changes in the amount of fluid and electrolyte (salt and other blood compounds) 
  - Psychological stress
  - Change in the levels of antiseizure medications

• There are two hormones that predominate in women, estrogen and progesterone. The proportion of these hormones changes during the menstrual cycle.  While Estrogen favors seizures, progesterone has a protective effect. Therefore seizures are more likely to occur whenever the progesterone level decreases or the estrogen level increases such as:
  - Just before the onset of the menstrual period  (decline in the levels of progesterone)
  - Just before ovulation in the middle of the cycle (increase in the levels of estrogen)
  - Due to anovulatory cycles (a menstrual cycle in which ovulation fails to occur and eggs are not released from the ovaries).   These are more common in women with epilepsy. Seizures tend to occur in the second half of the menstrual cycle because there is no increase in progesterone.

What should you do?
• Keep a diary of your seizures and menstrual periods.
• Discuss the possibility of catamenial epilepsy with your doctor.

Your doctor may treat you:
• By supplementation with reproductive hormones-natural progesterone
• By increasing doses of antiseizure medications during a particular time of your menstrual cycle
• There is a particular medication called Diamox that has some mild anti-seizure effect and is also a mild diuretic (water pill) which has shown to help in some patients.