Valproic acid and divalproex sodium - April 3, 2026
The FDA updated the Prescribing Information (PI). These updates provide new safety labeling information regarding hypersensitivity reactions, valproate use in women of childbearing potential, and drug-drug interactions
Section 4, Contraindications, was updated to include multiorgan hypersensitivity, serious dermatologic reactions, and angioedema. The text was also updated in Section 5, Warnings and Precautions (Subsections 5.2, Structural Birth Defects, 5.3, Decreased IQ and Neurodevelopmental Disorders Following in utero Exposure, 5.4, Use in Women of Childbearing Potential, 5.13 Serious Dermatologic Reactions, 5.14, Angioedema), Section 6, Adverse Reactions, Subsections 7.1, Effects of Co-Administered Drugs on Valproate Clearance, 7.4, Cannabidiol, 8.1, Pregnancy, and Section 17, Patient Counseling Information. Extensive changes were also introduced to the Medication Guide.
The updates on hypersensitivity reactions are related to dermatologic adverse effects and angioedema, as follows:
- Serious dermatologic reactions that have been reported with valproate treatment include toxic epidermal necrolysis (TEN), Stevens Johnson syndrome (SJS), acute generalized exanthematous pustulosis (AGEP), and erythema multiforme (EM). Valproate should be discontinued at the first sign of a rash, unless the rash is clearly not drug related. If a rash occurs, the patient should be evaluated for signs and symptoms of Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS). If signs or symptoms suggest TEN/SJS/AGEP/EM, use of valproic acid should not be resumed, and alternative therapy should be considered.
- Angioedema has been reported in the postmarketing setting. Valproate should be discontinued immediately if symptoms of angioedema such as facial, perioral, or upper airway swelling occur. Valproate should be discontinued permanently if a clear alternative etiology for the reaction cannot be established.
The information regarding valproate use in women of childbearing potential includes the following updates:
- Data from epidemiological studies suggesting that exposure to valproate monotherapy in utero may be associated with an increased risk of autism spectrum disorder, intellectual disability, and attention deficit/hyperactivity disorder.
- For women of childbearing age who are receiving valproate in whom there is no suitable alternative therapy, refer to the recommendation for using dietary folic acid supplementation both prior to conception and during pregnancy (Subsection 5.4).
The information regarding drug-drug interactions includes the following updates:
- Methotrexate may decrease serum valproate levels and potentially result in increased frequency of seizures or bipolar symptoms. Prescribers should monitor serum valproate concentrations and clinical response when adding or discontinuing methotrexate and adjust valproate dosage, if necessary.
- Concomitant administration of valproate and cannabidiol has been associated with an increased risk of ALT and/or AST elevation. This has been manageable by dose reduction or, in more severe cases, by discontinuation of one or both drugs. Liver function, including serum transaminase and total bilirubin levels, should be monitored during concomitant treatment.
Topiramate – March 6th, 2026 –
The FDA has updated the Prescribing Information (PI). Contraindications (4) and Warnings and Precautions (5.11 and 5.13) have been updated to include additional recommendations and warnings for hypersensitivity reaction (angioedema, anaphylaxis, and drug reaction with eosinophilia and systemic symptoms (DRESS)/multiorgan hypersensitivity reactions). These updates detail how DRESS has been reported in those taking topiramate that can vary in presentation, and there is importance in immediate evaluation and discontinuation if there is no alternative etiology. Additionally, anaphylaxis and angioedema have been reported in post-marketing settings. It is recommended to discontinue and start alternative therapy if hypersensitivity reaction occurs. Lastly, if a patient has a history of hypersensitivity to topiramate, or the inactive ingredients, use of topiramate is contraindicated.