Depakote ER (divalproex sodium)
The following drug information is obtained from various newswires, published
medical journal articles, and medical conference presentations.
For the prophylaxis (prevention) of migraine headaches in adults
General Information
Depakote ER is an extended-release product used to prevent or
reduce the occurrence of migraines. It is indicated for the
prevention of migraine headaches in adults; however, there is no
evidence that it is useful in the acute treatment of migraine
headaches. Depakote ER is provided in tablet form.
About 23 million Americans suffer from migraine headaches, and
approximately 75% of migraine sufferers are women. Migraines may
also include nausea and/or vomiting, as well as sensitivity to
light and sound.
Clinical Results
The results of a multicenter, randomized, double-blind,
placebo-controlled, parallel-group trial demonstrated the
effectiveness of Depakote ER in the prevention of migraine
headaches. Patients who experienced two migraine headaches in a
four-week baseline period were randomized in a 1:1 ratio to
Depakote ER or placebo and treated for 12 weeks. Patients began
treatment on 500 mg once daily for one week, and were then
increased to 1000 mg once daily with an option to decrease the dose
back to 500 mg during the second week if intolerance occurred. 98
of 114 Depakote ER-treated patients (86%) and 100 of 110
placebo-treated patients (91%) treated at least two weeks
maintained the 1000 mg once daily dose for the duration of their
treatment. Treatment outcome was based on the reduction of the
four-week migraine headache rate in the treatment period compared
to the baseline period.
Two hundred and two patients (101 in each treatment group)
completed the treatment period. The mean reduction in the four-week
migraine headache rate was 1.2 from a baseline mean of 4.4 in the
Depakote ER group, versus 0.6 from a baseline mean of 4.2 in the
placebo group. The treatment difference was statistically
significant. (from FDA Label)
Side Effects
Adverse effects reported with Depakote ER use include (but are
not limited to) the following:
- Nausea
- Diarrhea
- Vomiting
- Abdominal pain
- Dizziness
- Tremor
- Weight gain
- Back pain
Depakote ER generally should not be administered to patients
with hepatic (liver) disease or significant hepatic
dysfunction.
Before using Depakote ER, a woman who can become pregnant should
consider the fact that Depakote ER has been associated with birth
defects, in particular, with spina bifida and other defects related
to failure of the spinal canal to close normally.
Mechanism of Action
Divalproex sodium is a stable co-ordination compound comprised
of sodium valproate and valproic acid in a 1:1 molar relationship
and formed during the partial neutralization of valproic acid with
0.5 equivalent of sodium hydroxide. Chemically, it is designated as
sodium hydrogen bis(2-propylpentanoate).
Divalproex sodium dissociates to the valproate ion in the
gastrointestinal tract. The mechanisms by which valproate exerts
its therapeutic effects have not been established. (from FDA
Label).
Additional Information
