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 of valproate therapy. 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 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,
ophthalmoplegia, 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 should only be used after other anticonvulsants have failed.
This older group of patients should be closely monitored during treatment with Depakote 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 BOX WARNING and CONTRAINDICATIONS].
Birth Defects
Valproate can cause fetal harm when administered to a pregnant woman. Pregnancy registry data
show that 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].
Valproate use is contraindicated during pregnancy in women being treated for prophylaxis of
migraine headaches. Women with epilepsy or bipolar disorder who are pregnant or who plan to
become pregnant should not be treated with valproate unless other treatments have failed tos
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 BOX 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 BOX 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. 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 reaction 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, 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 lifethreatening.
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.
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 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 to notify 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].
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 and for manic episodes associated with bipolar disorder
[see WARNINGS AND PRECAUTIONS].
Pregnancy Category X for prophylaxis of migraine headaches [see CONTRAINDICATIONS].
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).
- Valproate is contraindicated during pregnancy in women being treated for prophylaxis of
migraine headaches.
- Valproate should not be used to treat women with epilepsy or bipolar disorder 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 BOX 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 BOX WARNING and WARNINGS AND PRECAUTIONS]. 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. 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 concentrations. 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].
There is insufficient information available to discern the safety and effectiveness of valproate for
the prophylaxis of migraines in patients over 65.