WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Hepatotoxicity
General Information On Hepatotoxicity
Hepatic failure resulting in fatalities has occurred in
patients receiving valproate. These incidents usually have occurred during the
first six months of treatment. Serious or fatal hepatotoxicity may be preceded
by non-specific symptoms such as malaise, weakness, lethargy, facial edema,
anorexia, and vomiting. In patients with epilepsy, a loss of seizure control
may also occur. Patients should be monitored closely for appearance of these
symptoms. Serum liver tests should be performed prior to therapy and at
frequent intervals thereafter, especially during the first six months. However,
healthcare providers should not rely totally on serum biochemistry since these
tests may not be abnormal in all instances, but should also consider the
results of careful interim medical history and physical examination.
Caution should be observed when administering valproate
products to patients with a prior history of hepatic disease. Patients on
multiple anticonvulsants, children, those with congenital metabolic disorders,
those with severe seizure disorders accompanied by mental retardation, and those
with organic brain disease may be at particular risk. See below, “Patients with
Known or Suspected Mitochondrial Disease.”
Experience has indicated that children under the age of
two years are at a considerably increased risk of developing fatal
hepatotoxicity, especially those with the aforementioned conditions. When
Depakote is used in this patient group, it should be used with extreme caution
and as a sole agent. The benefits of therapy should be weighed against the
risks. In progressively older patient groups experience in epilepsy has
indicated that the incidence of fatal hepatotoxicity decreases considerably.
Patients With Known Or Suspected Mitochondrial Disease
Depakote Sprinkle Capsules is contraindicated in patients
known to have mitochondrial disorders caused by POLG mutations and children
under two years of age who are clinically suspected of having a mitochondrial
disorder [see CONTRAINDICATIONS]. Valproate-induced acute liver failure
and liver-related deaths have been reported in patients with hereditary
neurometabolic syndromes caused by mutations in the gene for mitochondrial DNA
polymerase γ (POLG) (e.g., Alpers-Huttenlocher Syndrome) at a higher rate than
those without these syndromes. Most of the reported cases of liver failure in
patients with these syndromes have been identified in children and adolescents.
POLG-related disorders should be suspected in patients
with a family history or suggestive symptoms of a POLG-related disorder,
including but not limited to unexplained encephalopathy, refractory epilepsy
(focal, myoclonic), status epilepticus at presentation, developmental delays,
psychomotor regression, axonal sensorimotor neuropathy, myopathy cerebellar ataxia, opthalmoplegia, or complicated migraine with occipital aura. POLG
mutation testing should be performed in accordance with current clinical
practice for the diagnostic evaluation of such disorders. The A467T and W748S
mutations are present in approximately 2/3 of patients with autosomal recessive
POLG-related disorders.
In patients over two years of age who are clinically
suspected of having a hereditary mitochondrial disease, Depakote Sprinkle
Capsules should only be used after other anticonvulsants have failed. This
older group of patients should be closely monitored during treatment with
Depakote Sprinkle Capsules for the development of acute liver injury with
regular clinical assessments and serum liver test monitoring.
The drug should be discontinued immediately in the
presence of significant hepatic dysfunction, suspected or apparent. In some
cases, hepatic dysfunction has progressed in spite of discontinuation of drug [see
BOXED WARNING and CONTRAINDICATIONS].
Birth Defects
Valproate can cause fetal harm when administered to a
pregnant woman. Pregnancy registry data show maternal valproate use can cause
neural tube defects and other structural abnormalities (e.g., craniofacial
defects, cardiovascular malformations, hypospadias, limb malformations). The
rate of congenital malformations among babies born to mothers using valproate
is about four times higher than the rate among babies born to epileptic mothers
using other anti-seizure monotherapies. Evidence suggests that folic acid supplementation
prior to conception and during the first trimester of pregnancy decreases the
risk for congenital neural tube defects in the general population.
Decreased IQ Following In utero Exposure
Valproate can cause decreased IQ scores following in
utero exposure. Published epidemiological studies have indicated that
children exposed to valproate in utero have lower cognitive test scores
than children exposed in utero to either another antiepileptic drug or
to no antiepileptic drugs. The largest of these studies1 is a
prospective cohort study conducted in the United States and United Kingdom that
found that children with prenatal exposure to valproate (n=62) had lower IQ
scores at age 6 (97 [95% C.I. 94-101]) than children with prenatal exposure to
the other antiepileptic drug monotherapy treatments evaluated: lamotrigine (108
[95% C.I. 105–110]), carbamazepine (105 [95% C.I. 102–108]), and phenytoin (108
[95% C.I. 104–112]). It is not known when during pregnancy cognitive effects in
valproate-exposed children occur. Because the women in this study were exposed
to antiepileptic drugs throughout pregnancy, whether the risk for decreased IQ
was related to a particular time period during pregnancy could not be assessed.
Although all of the available studies have methodological
limitations, the weight of the evidence supports the conclusion that valproate
exposure in utero can cause decreased IQ in children.
In animal studies, offspring with prenatal exposure to
valproate had malformations similar to those seen in humans and demonstrated
neurobehavioral deficits [see Use in Specific Populations].
Women with epilepsy who are pregnant or who plan to become
pregnant should not be treated with valproate unless other treatments have
failed to provide adequate symptom control or are otherwise unacceptable. In
such women, the benefits of treatment with valproate during pregnancy may still
outweigh the risks.
Use In Women Of Childbearing Potential
Because of the risk to the fetus of decreased IQ and
major congenital malformations (including neural tube defects), which may occur
very early in pregnancy, valproate should not be administered to a woman of
childbearing potential unless the drug is essential to the management of her
medical condition. This is especially important when valproate use is
considered for a condition not usually associated with permanent injury or
death (e.g., migraine). Women should use effective contraception while using
valproate. Women who are planning a pregnancy should be counseled regarding the
relative risks and benefits of valproate use during pregnancy, and alternative
therapeutic options should be considered for these patients [see BOXED
WARNING and Use In Specific Populations].
To prevent major seizures, valproate should not be
discontinued abruptly, as this can precipitate status epilepticus with
resulting maternal and fetal hypoxia and threat to life.
Evidence suggests that folic acid supplementation prior
to conception and during the first trimester of pregnancy decreases the risk
for congenital neural tube defects in the general population. It is not known
whether the risk of neural tube defects or decreased IQ in the offspring of
women receiving valproate is reduced by folic acid supplementation. Dietary
folic acid supplementation both prior to conception and during pregnancy should
be routinely recommended for patients using valproate.
Pancreatitis
Cases of life-threatening pancreatitis have been reported
in both children and adults receiving valproate. Some of the cases have been
described as hemorrhagic with rapid progression from initial symptoms to death.
Some cases have occurred shortly after initial use as well as after several
years of use. The rate based upon the reported cases exceeds that expected in
the general population and there have been cases in which pancreatitis recurred
after rechallenge with valproate. In clinical trials, there were 2 cases of
pancreatitis without alternative etiology in 2,416 patients, representing 1,044
patient-years experience. Patients and guardians should be warned that
abdominal pain, nausea, vomiting, and/or anorexia can be symptoms of
pancreatitis that require prompt medical evaluation. If pancreatitis is
diagnosed, Depakote should ordinarily be discontinued. Alternative treatment
for the underlying medical condition should be initiated as clinically
indicated [see BOXED WARNING].
Urea Cycle Disorders
Depakote is contraindicated in patients with known urea
cycle disorders (UCD). Hyperammonemic encephalopathy, sometimes fatal, has been
reported following initiation of valproate therapy in patients with urea cycle
disorders, a group of uncommon genetic abnormalities, particularly ornithine
transcarbamylase deficiency. Prior to the initiation of Depakote therapy,
evaluation for UCD should be considered in the following patients: 1) those
with a history of unexplained encephalopathy or coma, encephalopathy associated
with a protein load, pregnancy-related or postpartum encephalopathy,
unexplained mental retardation, or history of elevated plasma ammonia or
glutamine; 2) those with cyclical vomiting and lethargy, episodic extreme
irritability, ataxia, low BUN, or protein avoidance; 3) those with a family
history of UCD or a family history of unexplained infant deaths (particularly
males); 4) those with other signs or symptoms of UCD. Patients who develop
symptoms of unexplained hyperammonemic encephalopathy while receiving valproate
therapy should receive prompt treatment (including discontinuation of valproate
therapy) and be evaluated for underlying urea cycle disorders [see CONTRAINDICATIONS
and Hyperammonemia and Encephalopathy associated with Concomitant Topiramate Use].
Suicidal Behavior And Ideation
Antiepileptic drugs (AEDs), including Depakote, increase
the risk of suicidal thoughts or behavior in patients taking these drugs for
any indication. Patients treated with any AED for any indication should be
monitored for the emergence or worsening of depression, suicidal thoughts or
behavior, and/or any unusual changes in mood or behavior.
Pooled analyses of 199 placebo-controlled clinical trials
(mono- and adjunctive therapy) of 11 different AEDs showed that patients
randomized to one of the AEDs had approximately twice the risk (adjusted
Relative Risk 1.8, 95% CI:1.2, 2.7) of suicidal thinking or behavior compared
to patients randomized to placebo. In these trials, which had a median
treatment duration of 12 weeks, the estimated incidence rate of suicidal
behavior or ideation among 27,863 AED-treated patients was 0.43%, compared to
0.24% among 16,029 placebo-treated patients, representing an increase of
approximately one case of suicidal thinking or behavior for every 530 patients
treated. There were four suicides in drug-treated patients in the trials and
none in placebo-treated patients, but the number is too small to allow any
conclusion about drug effect on suicide.
The increased risk of suicidal thoughts or behavior with
AEDs was observed as early as one week after starting drug treatment with AEDs
and persisted for the duration of treatment assessed. Because most trials
included in the analysis did not extend beyond 24 weeks, the risk of suicidal
thoughts or behavior beyond 24 weeks could not be assessed.
The risk of suicidal thoughts or behavior was generally
consistent among drugs in the data analyzed. The finding of increased risk with
AEDs of varying mechanisms of action and across a range of indications suggests
that the risk applies to all AEDs used for any indication. The risk did not
vary substantially by age (5-100 years) in the clinical trials analyzed.
Table 1 shows absolute and relative risk by indication
for all evaluated AEDs.
Table 1: Risk by indication for antiepileptic drugs in
the pooled analysis
Indication |
Placebo Patients with Events Per 1,000 Patients |
Drug Patients with Events Per 1,000 Patients |
Relative Risk: Incidence of Events in Drug Patients/Incidence in Placebo Patients |
Risk Difference: Additional Drug Patients with Events Per 1,000 Patients |
Epilepsy |
1.0 |
3.4 |
3.5 |
2.4 |
Psychiatric |
5.7 |
8.5 |
1.5 |
2.9 |
Other |
1.0 |
1.8 |
1.9 |
0.9 |
Total |
2.4 |
4.3 |
1.8 |
1.9 |
The relative risk for suicidal
thoughts or behavior was higher in clinical trials for epilepsy than in
clinical trials for psychiatric or other conditions, but the absolute risk
differences were similar for the epilepsy and psychiatric indications.
Anyone considering prescribing
Depakote or any other AED must balance the risk of suicidal thoughts or
behavior with the risk of untreated illness. Epilepsy and many other illnesses
for which AEDs are prescribed are themselves associated with morbidity and
mortality and an increased risk of suicidal thoughts and behavior. Should
suicidal thoughts and behavior emerge during treatment, the prescriber needs to
consider whether the emergence of these symptoms in any given patient may be
related to the illness being treated.
Patients, their caregivers, and
families should be informed that AEDs increase the risk of suicidal thoughts
and behavior and should be advised of the need to be alert for the emergence or
worsening of the signs and symptoms of depression, any unusual changes in mood
or behavior, or the emergence of suicidal thoughts, behavior, or thoughts about
self-harm. Behaviors of concern should be reported immediately to healthcare
providers.
Bleeding And Other
Hematopoietic Disorders
Valproate is associated with
dose-related thrombocytopenia. In a clinical trial of valproate as monotherapy
in patients with epilepsy, 34/126 patients (27%) receiving approximately 50
mg/kg/day on average, had at least one value of platelets ≤ 75 x 109/L.
Approximately half of these patients had treatment discontinued, with return of
platelet counts to normal. In the remaining patients, platelet counts
normalized with continued treatment. In this study, the probability of
thrombocytopenia appeared to increase significantly at total valproate
concentrations of ≥ 110 mcg/mL (females) or ≥ 135 mcg/mL (males).
The therapeutic benefit which may accompany the higher doses should
therefore be weighed against the possibility of a greater incidence of adverse
effects. Valproate use has also been associated with decreases in other cell
lines and myelodysplasia.
Because of reports of cytopenias, inhibition of the
secondary phase of platelet aggregation, and abnormal coagulation parameters,
(e.g., low fibrinogen, coagulation factor deficiencies, acquired von
Willebrand's disease), measurements of complete blood counts and coagulation
tests are recommended before initiating therapy and at periodic intervals. It
is recommended that patients receiving Depakote be monitored for blood counts
and coagulation parameters prior to planned surgery and during pregnancy [see
Use in Specific Populations]. Evidence of hemorrhage, bruising, or a
disorder of hemostasis/coagulation is an indication for reduction of the dosage
or withdrawal of therapy.
Hyperammonemia
Hyperammonemia has been reported in association with
valproate therapy and may be present despite normal liver function tests. In
patients who develop unexplained lethargy and vomiting or changes in mental
status, hyperammonemic encephalopathy should be considered and an ammonia level
should be measured [see CONTRAINDICATIONS and Urea Cycle Disorders Hyperammonemia and Encephalopathy associated with Concomitant Topiramate Use]. Hyperammonemia should also be considered in patients who
present with hypothermia [see Hypothermia]. If ammonia is
increased, valproate therapy should be discontinued. Appropriate interventions
for treatment of hyperammonemia should be initiated, and such patients should
undergo investigation for underlying urea cycle disorders [see
CONTRAINDICATIONS and Urea Cycle Disorders Hyperammonemia and Encephalopathy associated with Concomitant Topiramate Use].
Asymptomatic elevations of ammonia are more common and
when present, require close monitoring of plasma ammonia levels. If the
elevation persists, discontinuation of valproate therapy should be considered.
Hyperammonemia And Encephalopathy Associated With Concomitant
Topiramate Use
Concomitant administration of topiramate and valproate
has been associated with hyperammonemia with or without encephalopathy in
patients who have tolerated either drug alone. Clinical symptoms of
hyperammonemic encephalopathy often include acute alterations in level of
consciousness and/or cognitive function with lethargy or vomiting. Hypothermia
can also be a manifestation of hyperammonemia [see Hypothermia].
In most cases, symptoms and signs abated with discontinuation of either drug.
This adverse event is not due to a pharmacokinetic interaction. Patients with
inborn errors of metabolism or reduced hepatic mitochondrial activity may be at
an increased risk for hyperammonemia with or without encephalopathy. Although
not studied, an interaction of topiramate and valproate may exacerbate existing
defects or unmask deficiencies in susceptible persons. In patients who develop
unexplained lethargy, vomiting, or changes in mental status, hyperammonemic
encephalopathy should be considered and an ammonia level should be measured [see
CONTRAINDICATIONS and Urea Cycle Disorders and Hyperammonemia].
Hypothermia
Hypothermia, defined as an unintentional drop in body
core temperature to < 35°C (95°F), has been reported in association with
valproate therapy both in conjunction with and in the absence of
hyperammonemia. This adverse reaction can also occur in patients using
concomitant topiramate with valproate after starting topiramate treatment or
after increasing the daily dose of topiramate [see DRUG INTERACTIONS].
Consideration should be given to stopping valproate in patients who develop
hypothermia, which may be manifested by a variety of clinical abnormalities
including lethargy, confusion, coma, and significant alterations in other major
organ systems such as the cardiovascular and respiratory systems. Clinical
management and assessment should include examination of blood ammonia levels.
Drug Reaction With Eosinophilia And Systemic Symptoms
(DRESS)/Multiorgan Hypersensitivity Reactions
Drug Reaction with Eosinophilia and Systemic Symptoms
(DRESS), also known as Multiorgan Hypersensitivity, has been reported in
patients taking valproate. DRESS may be fatal or life-threatening. DRESS
typically, although not exclusively, presents with fever, rash, and/or
lymphadenopathy, in association with other organ system involvement, such as
hepatitis, nephritis, hematological abnormalities, myocarditis, or myositis
sometimes resembling an acute viral infection. Eosinophilia is often present.
Because this disorder is variable in its expression, other organ systems not
noted here may be involved. It is important to note that early manifestations
of hypersensitivity, such as fever or lymphadenopathy, may be present even
though rash is not evident. If such signs or symptoms are present, the patient
should be evaluated immediately. Valproate should be discontinued and not be
resumed if an alternative etiology for the signs or symptoms cannot be
established.
Interaction With Carbapenem Antibiotics
Carbapenem antibiotics (for example, ertapenem, imipenem,
meropenem; this is not a complete list) may reduce serum valproate
concentrations to subtherapeutic levels, resulting in loss of seizure control.
Serum valproate concentrations should be monitored frequently after initiating
carbapenem therapy. Alternative antibacterial or anticonvulsant therapy should
be considered if serum valproate concentrations drop significantly or seizure
control deteriorates [see DRUG INTERACTIONS].
Somnolence In The Elderly
In a double-blind, multicenter trial of valproate in
elderly patients with dementia (mean age = 83 years), doses were increased by
125 mg/day to a target dose of 20 mg/kg/day. A significantly higher proportion
of valproate patients had somnolence compared to placebo, and although not
statistically significant, there was a higher proportion of patients with
dehydration. Discontinuations for somnolence were also significantly higher
than with placebo. In some patients with somnolence (approximately one-half),
there was associated reduced nutritional intake and weight loss. There was a
trend for the patients who experienced these events to have a lower baseline
albumin concentration, lower valproate clearance, and a higher BUN. In elderly
patients, dosage should be increased more slowly and with regular monitoring
for fluid and nutritional intake, dehydration, somnolence, and other adverse
reactions. Dose reductions or discontinuation of valproate should be considered
in patients with decreased food or fluid intake and in patients with excessive
somnolence [see DOSAGE AND ADMINISTRATION].
Monitoring: Drug Plasma Concentration
Since valproate may interact with concurrently
administered drugs which are capable of enzyme induction, periodic plasma
concentration determinations of valproate and concomitant drugs are recommended
during the early course of therapy [see DRUG INTERACTIONS].
Effect On Ketone And Thyroid Function Tests
Valproate is partially eliminated in the urine as a
keto-metabolite which may lead to a false interpretation of the urine ketone
test.
There have been reports of altered thyroid function tests
associated with valproate. The clinical significance of these is unknown [see ADVERSE
REACTIONS].
Effect On HIV And CMV Viruses Replication
There are in vitro studies that suggest valproate
stimulates the replication of the HIV and CMV viruses under certain
experimental conditions. The clinical consequence, if any, is not known.
Additionally, the relevance of these in vitro findings is uncertain for
patients receiving maximally suppressive antiretroviral therapy. Nevertheless,
these data should be borne in mind when interpreting the results from regular
monitoring of the viral load in HIV infected patients receiving valproate or
when following CMV infected patients clinically.
Medication Residue In The Stool
There have been rare reports of medication residue in the
stool. Some patients have had anatomic (including ileostomy or colostomy) or
functional gastrointestinal disorders with shortened GI transit times. In some
reports, medication residues have occurred in the context of diarrhea. It is
recommended that plasma valproate levels be checked in patients who experience
medication residue in the stool, and patients' clinical condition should be
monitored. If clinically indicated, alternative treatment may be considered.
Patient Counseling Information
Advise the patient to read the FDA-approved patient
labeling (Medication Guide).
Hepatotoxicity
Warn patients and guardians that nausea, vomiting,
abdominal pain, anorexia, diarrhea, asthenia, and/or jaundice can be symptoms
of hepatotoxicity and, therefore, require further medical evaluation promptly [see
WARNINGS AND PRECAUTIONS].
Pancreatitis
Warn patients and guardians that abdominal pain, nausea,
vomiting, and/or anorexia can be symptoms of pancreatitis and, therefore,
require further medical evaluation promptly [see WARNINGS AND PRECAUTIONS].
Birth Defects And Decreased IQ
Inform pregnant women and women of childbearing potential
that use of valproate during pregnancy increases the risk of birth defects and
decreased IQ in children who were exposed. Advise women to use effective
contraception while using valproate. When appropriate, counsel these patients
about alternative therapeutic options. This is particularly important when
valproate use is considered for a condition not usually associated with
permanent injury or death. Advise patients to read the Medication Guide, which
appears as the last section of the labeling [see WARNINGS AND PRECAUTIONS
and Use In Specific Populations].
Advise women of childbearing potential to discuss
pregnancy planning with their doctor and to contact their doctor immediately if
they think they are pregnant.
Encourage patients to enroll in the NAAED Pregnancy
Registry if they become pregnant. This registry is collecting information about
the safety of antiepileptic drugs during pregnancy. To enroll, patients can
call the toll free number 1-888-233-2334 [see Use In Specific Populations].
Suicidal Thinking And Behavior
Counsel patients, their caregivers, and families that
AEDs, including Depakote, may increase the risk of suicidal thoughts and
behavior and should be advised of the need to be alert for the emergence or
worsening of symptoms of depression, any unusual changes in mood or behavior,
or the emergence of suicidal thoughts, behavior, or thoughts about self-harm.
Instruct patients, caregivers, and families to report behaviors of concern
immediately to the healthcare providers [see WARNINGS AND PRECAUTIONS].
Hyperammonemia
Inform patients of the signs
and symptoms associated with hyperammonemic encephalopathy and be told to
inform the prescriber if any of these symptoms occur [see WARNINGS
AND PRECAUTIONS].
CNS Depression
Since valproate products may
produce CNS depression, especially when combined with another CNS depressant
(e.g., alcohol), advise patients not to engage in hazardous activities, such as
driving an automobile or operating dangerous machinery, until it is known that
they do not become drowsy from the drug.
Multiorgan Hypersensitivity
Reactions
Instruct patients that a fever
associated with other organ system involvement (rash, lymphadenopathy, etc.)
may be drug-related and should be reported to the physician immediately [see WARNINGS
AND PRECAUTIONS].
Medication Residue In The Stool
Instruct patients to notify
their healthcare provider if they notice a medication residue in the stool [see
WARNINGS AND PRECAUTIONS].
Administration Guide
DEPAKOTE®
Sprinkle Capsules
DIVALPROEX SODIUM DELAYED RELEASE CAPSULES
DEPAKOTE® Sprinkle Capsules (divalproex sodium delayed
release capsules) may be swallowed whole or the
capsule contents may be sprinkled onto soft food such as applesauce or pudding.
Serving Suggestions
Depakote® Sprinkle
Capsules (divalproex sodium delayed release capsules) provide the medicine that
your healthcare provider has prescribed. The sprinkles are flavorless. Soft
foods such as applesauce or pudding are best to use for mixing and taking
Depakote Sprinkles.
TO ADMINISTER WITH FOOD:
1. Hold the capsule so that the end marked “THIS END
UP” is straight up and the arrow on the capsule is up. The capsule is
extra large to help prevent spilling the DEPAKOTE Sprinkles, but it still must
be handled carefully.
2. To open the capsule, hold it carefully. As shown in
the picture, gently twist the capsule apart to separate the top from the
bottom. It may be helpful to hold the capsule over the food to which you will
add the sprinkles. If you spill any of the capsule contents, start over with a
new capsule and a new portion of food.
3. Place all the sprinkles onto a small amount (about a
teaspoonful) of soft food such as applesauce or pudding.
4. Make sure that all of the sprinkle and food mixture is
swallowed right away. Do not chew the sprinkle and food mixture. Drinking water
right after taking the sprinkle and food mixture will help make sure all
sprinkles are swallowed. Throw away any unused sprinkle and food mixture; do
not store any sprinkle and food mixture for future use. Mix it each time, right
before it is taken.
Make sure this medicine is
taken exactly as your healthcare provider prescribed it. If you have any
questions, please contact your healthcare provider or pharmacist. Keep all of
your healthcare provider's appointments as scheduled. Make sure that Depakote
Sprinkle Capsules and all other medicines are kept out of the reach of
children.
Note
You may see the specially
coated particles in Depakote Sprinkle Capsules in stool. If you do, you should
inform your healthcare provider.
Ask your healthcare provider or
pharmacist about possible side effects with Depakote Sprinkle Capsules. Store
Depakote Sprinkle Capsules below 77°F (25°C).
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, And Impairment Of Fertility
Carcinogenesis
Valproate was administered orally to rats and mice at doses
of 80 and 170 mg/kg/day (less than the maximum recommended human dose on a mg/m² basis) for two years. The primary findings were an increase in the
incidence of subcutaneous fibrosarcomas in high dose male rats receiving
valproate and a dose-related trend for benign pulmonary adenomas in male mice
receiving valproate. The significance of these findings for humans is unknown.
Mutagenesis
Valproate was not mutagenic in an in vitro bacterial
assay (Ames test), did not produce dominant lethal effects in mice, and did not
increase chromosome aberration frequency in an in vivo cytogenetic study in
rats. Increased frequencies of sister chromatid exchange (SCE) have been reported
in a study of epileptic children taking valproate, but this association was not
observed in another study conducted in adults. There is some evidence that
increased SCE frequencies may be associated with epilepsy. The biological
significance of an increase in SCE frequency is not known.
Impairment Of Fertility
Chronic toxicity studies of valproate in juvenile and
adult rats and dogs demonstrated reduced spermatogenesis and testicular atrophy
at oral doses of 400 mg/kg/day or greater in rats (approximately equivalent to
or greater than the maximum recommended human dose (MRHD) on a mg/m² basis)
and 150 mg/kg/day or greater in dogs (approximately 1.4 times the MRHD or
greater on a mg/m² basis). Fertility studies in rats have shown no
effect on fertility at oral doses of valproate up to 350 mg/kg/day
(approximately equal to the MRHD on a mg/m² basis) for 60 days. The
effect of valproate on testicular development and on sperm parameters and
fertility in humans is unknown.
Use In Specific Populations
Pregnancy
Pregnancy Category D for epilepsy [see WARNINGS
AND PRECAUTIONS].
Pregnancy Registry
To collect information on the effects of in utero exposure
to Depakote, physicians should encourage pregnant patients taking Depakote to
enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry.
This can be done by calling toll free 1-888-233-2334, and must be done by the
patients themselves. Information on the registry can be found at the website,
http://www.aedpregnancyregistry.org/.
Fetal Risk Summary
All pregnancies have a background risk of birth defects
(about 3%), pregnancy loss (about 15%), or other adverse outcomes regardless of
drug exposure. Maternal valproate use during pregnancy for any indication
increases the risk of congenital malformations, particularly neural tube
defects, but also malformations involving other body systems (e.g.,
craniofacial defects, cardiovascular malformations, hypospadias, limb malformations).
The risk of major structural abnormalities is greatest during the first
trimester; however, other serious developmental effects can occur with
valproate use throughout pregnancy. The rate of congenital malformations among
babies born to epileptic mothers who used valproate during pregnancy has been
shown to be about four times higher than the rate among babies born to
epileptic mothers who used other anti-seizure monotherapies [see WARNINGS
AND PRECAUTIONS].
Several published epidemiological studies have indicated
that children exposed to valproate in utero have lower IQ scores than
children exposed to either another antiepileptic drug in utero or to no
antiepileptic drugs in utero [see WARNINGS AND PRECAUTIONS].
An observational study has suggested that exposure to
valproate products during pregnancy may increase the risk of autism spectrum
disorders. In this study, children born to mothers who had used valproate
products during pregnancy had 2.9 times the risk (95% confidence interval [CI]:
1.7-4.9) of developing autism spectrum disorders compared to children born to
mothers not exposed to valproate products during pregnancy. The absolute risks
for autism spectrum disorders were 4.4% (95% CI: 2.6%-7.5%) in
valproate-exposed children and 1.5% (95% CI: 1.5%-1.6%) in children not exposed
to valproate products. Because the study was observational in nature,
conclusions regarding a causal association between in utero valproate
exposure and an increased risk of autism spectrum disorder cannot be considered
definitive.
In animal studies, offspring with prenatal exposure to
valproate had structural malformations similar to those seen in humans and
demonstrated neurobehavioral deficits.
Clinical Considerations
- Neural tube defects are the congenital malformation most
strongly associated with maternal valproate use. The risk of spina bifida
following in utero valproate exposure is generally estimated as 1-2%,
compared to an estimated general population risk for spina bifida of about 0.06
to 0.07% (6 to 7 in 10,000 births).
- Valproate can cause decreased IQ scores in children whose
mothers were treated with valproate during pregnancy.
- Because of the risks of decreased IQ, neural tube
defects, and other fetal adverse events, which may occur very early in
pregnancy:
- Valproate should not be administered to a woman of
childbearing potential unless the drug is essential to the management of her
medical condition. This is especially important when valproate use is
considered for a condition not usually associated with permanent injury or
death (e.g., migraine).
- Depakote Sprinkles should not be used to treat women with
epilepsy who are pregnant or who plan to become pregnant unless other
treatments have failed to provide adequate symptom control or are otherwise
unacceptable. In such women, the benefits of treatment with valproate during
pregnancy may still outweigh the risks. When treating a pregnant woman or a
woman of childbearing potential, carefully consider both the potential risks
and benefits of treatment and provide appropriate counseling.
- To prevent major seizures, women with epilepsy should not
discontinue valproate abruptly, as this can precipitate status epilepticus with
resulting maternal and fetal hypoxia and threat to life. Even minor seizures
may pose some hazard to the developing embryo or fetus. However,
discontinuation of the drug may be considered prior to and during pregnancy in
individual cases if the seizure disorder severity and frequency do not pose a
serious threat to the patient.
- Available prenatal diagnostic testing to detect neural
tube and other defects should be offered to pregnant women using valproate.
- Evidence suggests that folic acid supplementation prior
to conception and during the first trimester of pregnancy decreases the risk
for congenital neural tube defects in the general population. It is not known
whether the risk of neural tube defects or decreased IQ in the offspring of
women receiving valproate is reduced by folic acid supplementation. Dietary
folic acid supplementation both prior to conception and during pregnancy should
be routinely recommended for patients using valproate.
- Pregnant women taking valproate may develop clotting
abnormalities including thrombocytopenia, hypofibrinogenemia, and/or decrease
in other coagulation factors, which may result in hemorrhagic complications in
the neonate including death [see WARNINGS AND PRECAUTIONS]. If valproate
is used in pregnancy, the clotting parameters should be monitored carefully in
the mother. If abnormal in the mother, then these parameters should also be
monitored in the neonate.
- Patients taking valproate may develop hepatic failure [see BOXED WARNING and WARNINGS AND PRECAUTIONS]. Fatal cases of
hepatic failure in infants exposed to valproate in utero have also been
reported following maternal use of valproate during pregnancy.
- Hypoglycemia has been reported in neonates whose mothers
have taken valproate during pregnancy.
Data
Human
There is an extensive body of evidence demonstrating that
exposure to valproate in utero increases the risk of neural tube defects
and other structural abnormalities. Based on published data from the CDC's
National Birth Defects Prevention Network, the risk of spina bifida in the
general population is about 0.06 to 0.07%. The risk of spina bifida following in
utero valproate exposure has been estimated to be approximately 1 to 2%.
The NAAED Pregnancy Registry has reported a major
malformation rate of 9-11% in the offspring of women exposed to an average of
1,000 mg/day of valproate monotherapy during pregnancy. These data show up to a
five-fold increased risk for any major malformation following valproate
exposure in utero compared to the risk following exposure in utero to
other antiepileptic drugs taken in monotherapy. The major congenital
malformations included cases of neural tube defects, cardiovascular
malformations, craniofacial defects (e.g., oral clefts, craniosynostosis),
hypospadias, limb malformations (e.g., clubfoot, polydactyly), and
malformations of varying severity involving other body systems.
Published epidemiological studies have indicated that
children exposed to valproate in utero have lower IQ scores than
children exposed to either another antiepileptic drug in utero or to no
antiepileptic drugs in utero. The largest of these studies is a prospective
cohort study conducted in the United States and United Kingdom that found that
children with prenatal exposure to valproate (n=62) had lower IQ scores at age
6 (97 [95% C.I. 94-101]) than children with prenatal exposure to the other
anti-epileptic drug monotherapy treatments evaluated: lamotrigine (108 [95%
C.I. 105–110]), carbamazepine (105 [95% C.I. 102–108]) and phenytoin (108 [95%
C.I. 104–112]). It is not known when during pregnancy cognitive effects in
valproate-exposed children occur. Because the women in this study were exposed
to antiepileptic drugs throughout pregnancy, whether the risk for decreased IQ
was related to a particular time period during pregnancy could not be assessed.
Although all of the available studies have methodological
limitations, the weight of the evidence supports a causal association between
valproate exposure in utero and subsequent adverse effects on cognitive
development.
There are published case reports of fatal hepatic failure
in offspring of women who used valproate during pregnancy.
Animal
In developmental toxicity studies conducted in mice,
rats, rabbits, and monkeys, increased rates of fetal structural abnormalities,
intrauterine growth retardation, and embryo-fetal death occurred following
treatment of pregnant animals with valproate during organogenesis at clinically
relevant doses (calculated on a body surface area basis). Valproate induced
malformations of multiple organ systems, including skeletal, cardiac, and
urogenital defects. In mice, in addition to other malformations, fetal neural
tube defects have been reported following valproate administration during critical
periods of organogenesis, and the teratogenic response correlated with peak
maternal drug levels. Behavioral abnormalities (including cognitive, locomotor,
and social interaction deficits) and brain histopathological changes have also
been reported in mice and rat offspring exposed prenatally to clinically
relevant doses of valproate.
Nursing Mothers
Valproate is excreted in human milk. Caution should be
exercised when valproate is administered to a nursing woman.
Pediatric Use
Experience has indicated that pediatric patients under
the age of two years are at a considerably increased risk of developing fatal
hepatotoxicity, especially those with the aforementioned conditions [see BOXED
WARNING and WARNINGS AND PRECAUTIONS]. When valproate is used in
this patient group, it should be used with extreme caution and as a sole agent.
The benefits of therapy should be weighed against the risks. Above the age of 2
years, experience in epilepsy has indicated that the incidence of fatal hepatotoxicity
decreases considerably in progressively older patient groups.
Younger children, especially those receiving enzyme
inducing drugs, will require larger maintenance doses to attain targeted total
and unbound valproate concentrations. Pediatric patients (i.e., between 3
months and 10 years) have 50% higher clearances expressed on weight (i.e.,
mL/min/kg) than do adults. Over the age of 10 years, children have
pharmacokinetic parameters that approximate those of adults. The variability in
free fraction limits the clinical usefulness of monitoring total serum valproic
acid concentration. Interpretation of valproic acid concentrations in children
should include consideration of factors that affect hepatic metabolism and
protein binding.
Pediatric Clinical Trials
Depakote was studied in seven pediatric clinical trials.
Two of the pediatric studies were double-blinded
placebo-controlled trials to evaluate the efficacy of Depakote ER for the
indications of mania (150 patients aged 10 to 17 years, 76 of whom were on
Depakote ER) and migraine (304 patients aged 12 to 17 years, 231 of whom were
on Depakote ER). Efficacy was not established for either the treatment of
migraine or the treatment of mania. The most common drug-related adverse
reactions (reported > 5% and twice the rate of placebo) reported in the
controlled pediatric mania study were nausea, upper abdominal pain, somnolence,
increased ammonia, gastritis and rash.
The remaining five trials were long term safety studies.
Two six-month pediatric studies were conducted to evaluate the long-term safety
of Depakote ER for the indication of mania (292 patients aged 10 to 17 years).
Two twelve-month pediatric studies were conducted to evaluate the long-term
safety of Depakote ER for the indication of migraine (353 patients aged 12 to
17 years). One twelve-month study was conducted to evaluate the safety of
Depakote Sprinkle Capsules in the indication of partial seizures (169 patients
aged 3 to 10 years).
In these seven clinical trials, the safety and
tolerability of Depakote in pediatric patients were shown to be comparable to
those in adults [see ADVERSE REACTIONS].
Juvenile Animal Toxicology
In studies of valproate in immature animals, toxic
effects not observed in adult animals included retinal dysplasia in rats
treated during the neonatal period (from postnatal day 4) and nephrotoxicity in
rats treated during the neonatal and juvenile (from postnatal day 14) periods.
The no-effect dose for these findings was less than the maximum recommended
human dose on a mg/m² basis.
Geriatric Use
No patients above the age of 65 years were enrolled in
double-blind prospective clinical trials of mania associated with bipolar
illness. In a case review study of 583 patients, 72 patients (12%) were greater
than 65 years of age. A higher percentage of patients above 65 years of age
reported accidental injury, infection, pain, somnolence, and tremor.
Discontinuation of valproate was occasionally associated with the latter two
events. It is not clear whether these events indicate additional risk or
whether they result from preexisting medical illness and concomitant medication
use among these patients.
A study of elderly patients with dementia revealed drug
related somnolence and discontinuation for somnolence [see WARNINGS AND
PRECAUTIONS]. The starting dose should be reduced in these patients, and
dosage reductions or discontinuation should be considered in patients with excessive
somnolence [see DOSAGE AND ADMINISTRATION].
The capacity of elderly patients (age range: 68 to 89
years) to eliminate valproate has been shown to be reduced compared to younger
adults (age range: 22 to 26) [see CLINICAL PHARMACOLOGY].
Effect Of Disease
Liver Disease
[See BOXED WARNING, CONTRAINDICATIONS, WARNINGS
AND PRECAUTIONS, and CLINICAL PHARMACOLOGY]. Liver disease impairs
the capacity to eliminate valproate.