Valproic acid side effects

What does the patient leaflet say about side effects?

From the patient leaflet: What are the possible side effects of valproic acid?

See "What is the most important information I should know about valproic acid?" Valproic acid can cause serious side effects including: Bleeding problems: red or purple spots on your skin, bruising, pain and swelling into your joints due to bleeding or bleeding from your mouth or nose. High ammonia levels in your blood: feeling tired, vomiting, changes in mental status. Low body temperature (hypothermia): drop in your body temperature to less than 95°F, feeling tired, confusion, coma. Allergic (hypersensitivity) reactions: fever, skin rash, hives, sores in your mouth, blistering and peeling of your skin, swelling of your lymph nodes, swelling of your face, eyes, lips, tongue, or throat, trouble swallowing or breathing. Drowsiness or sleepiness in the elderly. This extreme drowsiness may cause you to eat or drink less than you normally would. […]

What does the label list?

From the label: adverse reactions

Most common adverse reactions (reported >5%) are abdominal pain, alopecia, amblyopia/blurred vision, amnesia, anorexia, asthenia, ataxia, bronchitis, constipation, depression, diarrhea, diplopia, dizziness, dyspepsia, dyspnea, ecchymosis, emotional lability, fever, flu syndrome, headache, increased appetite, infection, insomnia, nausea, nervousness, nystagmus, peripheral edema, pharyngitis, rhinitis, somnolence, thinking abnormal, thrombocytopenia, tinnitus, tremor, vomiting, weight gain, weight loss.

Table 3. Adverse Reactions Reported by ≥ 5% of Patients Treated with Divalproex Sodium During Placebo-Controlled Trial of Adjunctive Therapy for Complex Partial Seizures

Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.

From the label: adverse reactions, continued

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. …

What do FAERS reports show?

51,380 reports list valproic acid among the medicines taken, each a report of something that happened, not proof the medicine caused it; 6,386 are coded as a death and 21,799 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 15 reactions below, 10 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.

Reports received each year

• 1,610
• 2,330
• 2,696
• 2,573
• 2,798
• 5,033
• 5,532
• 4,041
• 3,755
• 3,324
• 1,507

• 2016
• 2017
• 2018
• 2019
• 2020
• 2021
• 2022
• 2023
• 2024
• 2025
• 2026

The 25 most reported reactions

• Drug Ineffective (a use or a product term, not a reaction)5,119
• Drug Interaction (a use or a product term, not a reaction)4,718
• Off Label Use (a use or a product term, not a reaction)3,261
• Toxicity To Various Agents2,770
• Seizure (a use or a product term, not a reaction)2,692
• Somnolence (named in the label)2,253
• Foetal Exposure During Pregnancy (a use or a product term, not a reaction)1,944
• Pyrexia1,610
• Condition Aggravated (a use or a product term, not a reaction)1,574
• Depression1,519
• Epilepsy (a use or a product term, not a reaction)1,500
• Overdose (a use or a product term, not a reaction)1,427
• Completed Suicide (an outcome recorded in the report)1,371
• Vomiting (named in the label)1,342
• Product Use In Unapproved Indication (a use or a product term, not a reaction)1,243
• Fatigue1,194
• Convulsion (named in the label)1,117
• Tremor (named in the label)1,113
• Hypotension (named in the label)1,102
• Aggression (named in the label)1,090
• Pneumonia (named in the label)1,089
• Weight Increased1,085
• Thrombocytopenia (named in the label)1,081
• Nausea (named in the label)1,078
• Status Epilepticus (named in the label)1,078

What next?

Valproic acid: the full record

label, generics, price, shortages, recalls

Report a side effect to the FDA

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