Valproic Acid

FDA Drug Information • Also known as: Valproic, Valproic Acid

Brand Names
Valproic, Valproic Acid
Drug Class
Anti-epileptic Agent [EPC], Mood Stabilizer [EPC]
Route
ORAL
Dosage Form
SOLUTION
Product Type
HUMAN PRESCRIPTION DRUG

⚠ Boxed Warning (Black Box)

Hepatotoxicity General Population: Hepatic failure resulting in fatalities has occurred in patients receiving valproate and its derivatives. These incidents usually ... WARNING: LIFE THREATENING ADVERSE REACTIONS Hepatotoxicity General Population: Hepatic failure resulting in fatalities has occurred in patients receiving valproate and its derivatives. 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 [see WARNINGS AND PRECAUTIONS (5.1)]. Children under the age of two years are at a considerably increased risk of developing fatal hepatotoxicity, especially those on multiple anticonvulsants, those with congenital metabolic disorders, those with severe seizure disorders accompanied by mental retardation, and those with organic brain disease. When valproic acid products are used in this patient group, they should be used with extreme caution and as a sole agent. The benefits of therapy should be weighed against the risks. The incidence of fatal hepatotoxicity decreases considerably in progressively older patient groups. Patients with Mitochondrial Disease: There is an increased risk of valproate-induced acute liver failure and resultant deaths in patients with hereditary neurometabolic syndromes caused by DNA mutations of the mitochondrial DNA Polymerase γ (POLG) gene (e.g. Alpers-Huttenlocher Syndrome). Valproic acid 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 (4)]. In patients over two years of age who are clinically suspected of having a hereditary mitochondrial disease, valproic acid should only be used after other anticonvulsants have failed. This older group of patients should be closely monitored during treatment with valproic acid for the development of acute liver injury with regular clinical assessments and serum liver testing. POLG mutation screening should be performed in accordance with current clinical practice [see WARNINGS AND PRECAUTIONS (5.1)]. Fetal Risk Valproate can cause major congenital malformations, particularly neural tube defects (e.g., spina bifida). In addition, valproate can cause decreased IQ scores following in utero exposure. Valproate should only be used to treat pregnant women with epilepsy if other medications have failed to control their symptoms or are otherwise unacceptable. 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 [see WARNINGS AND PRECAUTIONS (5.2, 5.3, 5.4)]. A Medication Guide describing the risks of valproate is available for patients [see PATIENT COUNSELING INFORMATION (17)]. 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 a rapid progression from initial symptoms to death. Cases have been reported shortly after initial use as well as after several years of use. 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, valproate should ordinarily be discontinued. Alternative treatment for the underlying medical condition should be initiated as clinically indicated [see WARNINGS AND PRECAUTIONS (5.5)].

Description

Valproic acid, USP is a carboxylic acid designated as 2-propylpentanoic acid. It is also known as dipropylacetic acid. Valproic acid has the following structure: [Chemical Structure] Valproic acid (pKa 4.8) has a molecular weight of 144 and occurs as a colorless liquid with a characteristic odor. It is slightly soluble in water (1.3 mg/mL) and very soluble in organic solvents. Valproic Acid Capsules, USP are antiepileptics for oral administration. Each soft gelatin capsule contains 250 mg valproic acid, USP. Inactive Ingredients Peanut oil, gelatin, glycerin and titanium dioxide

What Is Valproic Acid Used For?

These highlights do not include all the information needed to use VALPROIC ACID CAPSULES safely and effectively. See full prescribing information for VALPROIC ACID CAPSULES. VALPROIC ACID capsules for oral use Initial U.S. Approval: 1978 WARNING: LIFE THREATENING ADVERSE REACTIONS SEE FULL PRESCRIBING INFORMATION FOR COMPLETE BOXED WARNING. Hepatotoxicity, including fatalities, usually during the first 6 months of treatment. Children under the age of two years and patients with mitochondrial disorders are at higher risk. Monitor patients closely, and perform serum liver testing prior to therapy and at frequent intervals thereafter (5.1) Fetal Risk, particularly neural tube defects, other major malformations, and decreased IQ (5.2, 5.3, 5.4) Pancreatitis, including fatal hemorrhagic cases (5.5) INDICATIONS AND USAGE Valproic Acid Capsules are an anti-epileptic drug indicated for: Monotherapy and adjunctive therapy of complex partial seizures; sole and adjunctive therapy of simple and complex absence seizures; adjunctive therapy in patients with multiple seizure types that include absence seizures (1) DOSAGE AND ADMINISTRATION Valproic acid capsules are intended for oral administration. (2.1) Simple and Complex Absence Seizures: Start at 10 to 15 mg/kg/day, increasing at 1 week intervals by 5 to 10 mg/kg/week until seizure control or limiting side effects (2.1) Safety of doses above 60 mg/kg/day is not established (2.1, 2.2) DOSAGE FORMS AND STRENGTHS Capsules: 250 mg valproic acid (3) CONTRAINDICATIONS Hepatic disease or significant hepatic dysfunction (4, 5.1) Known mitochondrial disorders caused by mutations in mitochondrial DNA polymerase γ (POLG) (4, 5.1) Suspected POLG-related disorder in children under two years of age (4, 5.1) Known hypersensitivity to the drug (4, 5.12) Urea cycle disorders (4, 5.6) WARNINGS AND PRECAUTIONS Hepatotoxicity; evaluate high risk populations and monitor serum liver tests (5.1) Birth defects and decreased IQ following in utero exposure; only use to treat pregnant women with epilepsy if other medications are unacceptable; should not be administered to a woman of childbearing potential unless essential (5.2, 5.3, 5.4) Pancreatitis; valproic acid capsules should ordinarily be discontinued (5.5) Suicidal behavior or ideation; Antiepileptic drugs, including valproic acid capsules, increase the risk of suicidal thoughts or behavior (5.7) Bleeding and other hematopoietic disorders; monitor platelet counts and coagulation tests (5.8) Hyperammonemia and hyperammonemic encephalopathy; measure ammonia level if unexplained lethargy and vomiting or changes in mental status and also with concomitant topiramate use; consider discontinuation of valproate therapy (5.6, 5.9, 5.10) Hypothermia; Hypothermia has been reported during valproate therapy with or without associated hyperammonemia. This adverse reaction can also occur in patients using concomitant topiramate (5.11) Drug Reaction with Eosinophilia and Systemic Symptoms...

Dosage and Administration

2.1 Epilepsy Valproic acid capsules are intended for oral administration. Valproic acid capsules should be swallowed whole without chewing to avoid local irritation of the mouth and throat. Patients should be informed to take valproic acid capsules every day as prescribed. If a dose is missed it should be taken as soon as possible, unless it is almost time for the next dose. If a dose is skipped, the patient should not double the next dose. Valproic acid capsules are indicated as monotherapy and adjunctive therapy in complex partial seizures in adults and pediatric patients down to the age of 10 years, and in simple and complex absence seizures. As the valproic acid capsules dosage is titrated upward, concentrations of clonazepam, diazepam, ethosuximide, lamotrigine, tolbutamide, phenobarbital, carbamazepine, and/or phenytoin may be affected [see DRUG INTERACTIONS (7.2)]. Complex Partial Seizures For adults and children 10 years of age or older. Monotherapy (Initial Therapy) Valproic acid capsules have not been systematically studied as initial therapy. Patients should initiate therapy at 10 to 15 mg/kg/day. The dosage should be increased by 5 to 10 mg/kg/week to achieve optimal clinical response. Ordinarily, optimal clinical response is achieved at daily doses below 60 mg/kg/day. If satisfactory clinical response has not been achieved, plasma levels should be measured to determine whether or not they are in the usually accepted therapeutic range (50 to 100 mcg/mL). No recommendation regarding the safety of valproate for use at doses above 60 mg/kg/day can be made. The probability of thrombocytopenia increases significantly at total trough valproate plasma concentrations above 110 mcg/mL in females and 135 mcg/mL in males. The benefit of improved seizure control with higher doses should be weighed against the possibility of a greater incidence of adverse reactions. Conversion to Monotherapy Patients should initiate therapy at 10 to 15 mg/kg/day. The dosage should be increased by 5 to 10 mg/kg/week to achieve optimal clinical response. Ordinarily, optimal clinical response is achieved at daily doses below 60 mg/kg/day. If satisfactory clinical response has not been achieved, plasma levels should be measured to determine whether or not they are in the usually accepted therapeutic range (50 to 100 mcg/mL). No recommendation regarding the safety of valproate for use at doses above 60 mg/kg/day can be made. Concomitant antiepilepsy drug (AED) dosage can ordinarily be reduced by approximately 25% every 2 weeks. This reduction may be started at initiation of valproic acid capsules therapy, or delayed by 1 to 2 weeks if there is a concern that seizures are likely to occur with a reduction. The speed and duration of withdrawal of the concomitant AED can be highly variable, and patients should be monitored closely during this period for increased seizure frequency. Adjunctive Therapy Valproic acid capsules may be added to the patient's regimen at a dosage...

Side Effects (Adverse Reactions)

The following serious adverse reactions are described below and elsewhere in the labeling: Hepatic failure [see WARNINGS AND PRECAUTIONS (5.1)] Birth defects [see WARNINGS AND PRECAUTIONS (5.2)] Decreased IQ following in utero exposure [see WARNINGS AND PRECAUTIONS (5.3)] Pancreatitis [see WARNINGS AND PRECAUTIONS (5.5)] Hyperammonemic encephalopathy [see WARNINGS AND PRECAUTIONS (5.6, 5.9, 5.10)] Suicidal behavior and ideation [see WARNINGS AND PRECAUTIONS (5.7)] Bleeding and other hematopoietic disorders [see WARNINGS AND PRECAUTIONS (5.8)] Hypothermia [see WARNINGS AND PRECAUTIONS (5.11)] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan hypersensitivity reactions [see WARNINGS AND PRECAUTIONS (5.12)] Somnolence in the elderly [see WARNINGS AND PRECAUTIONS (5.14)] Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. 6.1 Epilepsy The data described in the following section were obtained using divalproex sodium tablets. Based on a placebo-controlled trial of adjunctive therapy for treatment of complex partial seizures, divalproex sodium tablets were generally well tolerated with most adverse reactions rated as mild to moderate in severity. Intolerance was the primary reason for discontinuation in the divalproex sodium tablets-treated patients (6%), compared to 1% of placebo-treated patients. Table 3 lists treatment-emergent adverse reactions which were reported by ≥ 5% of divalproex sodium-treated patients and for which the incidence was greater than in the placebo group, in a placebo-controlled trial of adjunctive therapy for treatment of complex partial seizures. Since patients were also treated with other antiepilepsy drugs, it is not possible, in most cases, to determine whether the following adverse reactions can be ascribed to divalproex sodium tablets alone, or the combination of divalproex sodium tablets and other antiepilepsy drugs. Table 3. Adverse Reactions Reported by ≥ 5% of Patients Treated with Divalproex Sodium Tablets During Placebo-Controlled Trial of Adjunctive Therapy for Complex Partial Seizures Body System/Reaction Divalproex Sodium Tablets (%) (n = 77) Placebo (%) (n = 70) Body as a Whole Headache 31 21 Asthenia 27 7 Fever 6 4 Gastrointestinal System Nausea 48 14 Vomiting 27 7 Abdominal Pain 23 6 Diarrhea 13 6 Anorexia 12 0 Dyspepsia 8 4 Constipation 5 1 Nervous System Somnolence 27 11 Tremor 25 6 Dizziness 25 13 Diplopia 16 9 Amblyopia/Blurred Vision 12 9 Ataxia 8 1 Nystagmus 8 1 Emotional Lability 6 4 Thinking Abnormal 6 0 Amnesia 5 1 Respiratory System Flu Syndrome 12 9 Infection 12 6 Bronchitis 5 1 Rhinitis 5 4 Other Alopecia 6 1 Weight Loss 6 0 Table 4 lists treatment-emergent adverse reactions which were reported by ≥ 5% of patients in the high dose divalproex sodium group, and for which the incidence was greater than in the low dose group, in a controlled trial of divalproex sodium tablets monotherapy treatment of complex partial seizures. Since patients were being titrated off another antiepilepsy drug during the first portion of the trial, it is not possible, in many cases, to determine whether the following adverse reactions can be ascribed to divalproex sodium tablets alone, or the combination of divalproex sodium tablets and other antiepilepsy drugs. Table 4. Adverse Reactions Reported by ≥ 5% of Patients in the High Dose Group in the Controlled Trial of Divalproex Sodium Tablets Monotherapy for Complex Partial Seizures* Body System/Reaction High Dose (%) (n = 131) Low Dose (%) (n = 134) * Headache was the only adverse reaction that occurred in ≥ 5% of patients in the high dose group and at an equal or greater incidence in the low dose group. Body as a Whole Asthenia 21 10 Digestive System Nausea 34 26 Diarrhea 23 19 Vomiting 23 15 Abdominal Pain 12 9...

Drug Interactions

7.1 Effects of Coadministered Drugs on Valproate Clearance Drugs that affect the level of expression of hepatic enzymes, particularly those that elevate levels of glucuronosyltransferases (such as ritonavir), may increase the clearance of valproate. For example, phenytoin, carbamazepine, and phenobarbital (or primidone) can double the clearance of valproate. Thus, patients on monotherapy will generally have longer half-lives and higher concentrations than patients receiving polytherapy with antiepilepsy drugs. In contrast, drugs that are inhibitors of cytochrome P450 isozymes, e.g., antidepressants, may be expected to have little effect on valproate clearance because cytochrome P450 microsomal mediated oxidation is a relatively minor secondary metabolic pathway compared to glucuronidation and beta-oxidation. Because of these changes in valproate clearance, monitoring of valproate and concomitant drug concentrations should be increased whenever enzyme inducing drugs are introduced or withdrawn. The following list provides information about the potential for an influence of several commonly prescribed medications on valproate pharmacokinetics. The list is not exhaustive nor could it be, since new interactions are continuously being reported. Drugs for which a potentially important interaction has been observed Aspirin A study involving the coadministration of aspirin at antipyretic doses (11 to 16 mg/kg) with valproate to pediatric patients (n = 6) revealed a decrease in protein binding and an inhibition of metabolism of valproate. Valproate free fraction was increased 4-fold in the presence of aspirin compared to valproate alone. The β-oxidation pathway consisting of 2-E-valproic acid, 3-OH-valproic acid, and 3-keto valproic acid was decreased from 25% of total metabolites excreted on valproate alone to 8.3% in the presence of aspirin. Caution should be observed if valproate and aspirin are to be coadministered. Carbapenem Antibiotics A clinically significant reduction in serum valproic acid concentration has been reported in patients receiving carbapenem antibiotics (for example, ertapenem, imipenem, meropenem; this is not a complete list) and may result in loss of seizure control. The mechanism of this interaction is not well understood. Serum valproic acid concentrations should be monitored frequently after initiating carbapenem therapy. Alternative antibacterial or anticonvulsant therapy should be considered if serum valproic acid concentrations drop significantly or seizure control deteriorates [see WARNINGS AND PRECAUTIONS (5.13)]. Cholestyramine Cholestyramine, when concurrently administered with valproic acid, led to, on average, a 14% decrease in plasma levels of valproic acid in a study conducted in 6 healthy subjects administered valproic acid and cholestyramine. Delaying the administration of cholestyramine relative to valproic acid administration by 3 hours may lessen the interaction. Estrogen-Containing Hormonal Contraceptives...

Contraindications

Valproic acid capsules should not be administered to patients with hepatic disease or significant hepatic dysfunction [see WARNINGS AND PRECAUTIONS (5.1)]. Valproic acid capsules are contraindicated in patients known to have mitochondrial disorders caused by mutations in mitochondrial DNA polymerase γ (POLG; e.g., Alpers-Huttenlocher Syndrome) and children under two years of age who are suspected of having a POLG-related disorder [see WARNINGS AND PRECAUTIONS (5.1)]. Valproic acid capsules are contraindicated in patients with known hypersensitivity to the drug [see WARNINGS AND PRECAUTIONS (5.12)]. Valproic acid capsules are contraindicated in patients with known urea cycle disorders [see WARNINGS AND PRECAUTIONS (5.6)].

Overdosage

Overdosage with valproate may result in somnolence, heart block, deep coma, and hypernatremia. Fatalities have been reported; however, patients have recovered from valproate levels as high as 2,120 mcg/mL. In overdose situations, the fraction of drug not bound to protein is high and hemodialysis or tandem hemodialysis plus hemoperfusion may result in significant removal of drug. The benefit of gastric lavage or emesis will vary with the time since ingestion. General supportive measures should be applied with particular attention to the maintenance of adequate urinary output. Naloxone has been reported to reverse the CNS depressant effects of valproate overdosage. Because naloxone could theoretically also reverse the antiepileptic effects of valproate, it should be used with caution in patients with epilepsy.

How Supplied

Valproic Acid Capsules, USP 250 mg are off-white colored soft gelatin capsules, imprinted with "U-S 250", containing Valproic Acid, USP, and packaged in bottles of 100 capsules . Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. Dispense in a tight, light-resistant container with a child-resistant closure.

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.