Two medicines, side by side
Clonazepam vs valproic acid
Clonazepam and valproic acid are both labeled for seizures and epilepsy. Drugs@FDA records approvals of clonazepam since 1975 and of valproic acid since 1978. Pharmacies paid $0.0244 per clonazepam 1 mg tablet and $0.243 per valproic acid 250 mg capsule (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, clonazepam is a benzodiazepine and valproic acid a mood stabilizer.
Check it at the source: the clonazepam FDA label on DailyMed (effective December 1, 2025); the valproic acid FDA label on DailyMed (effective January 24, 2025).
Highlights of the clonazepam record
Clonazepam (Klonopin) · label of December 1, 2025
RISKS FROM CONCOMITANT USE WITH OPIOIDS; ABUSE, MISUSE, AND ADDICTION; and DEPENDENCE AND WITHDRAWAL REACTIONS Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs for patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required.
Used for
From the label: indicationsSeizure Disorders Klonopin is useful alone or as an adjunct in the treatment of the Lennox-Gastaut syndrome (petit mal variant), akinetic, and myoclonic seizures. In patients with absence seizures (petit mal) who have failed to respond to succinimides, Klonopin may be useful. Some loss of effect may occur during the course of clonazepam treatment (see PRECAUTIONS: Loss of Effect ). […]
On the market
- Earliest approval on file
- June 4, 1975
- Generic labelers
- 31 labelers
- Pharmacy cost
- $0.0244 per tablet
Supply and safety
- Shortage
- In shortage
- Recalls
- 7
Highlights of the valproic acid record
Valproic acid (Depakene) · label of January 24, 2025
LIFE THREATENING ADVERSE REACTIONS 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.
Used for
From the label: indicationsValproic acid is 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 ) 1.1 Epilepsy Valproic acid is indicated as monotherapy and adjunctive therapy in the treatment of patients with complex partial seizures that occur either in isolation or in association with other types of seizures. […]
On the market
- Earliest approval on file
- February 28, 1978
- Generic labelers
- 22 labelers
- Pharmacy cost
- $0.243 per capsule
Supply and safety
- Shortage
- Listed; available
- Recalls
- 2
Source: FDA drug labels via openFDA (Clonazepam label of December 1, 2025, Valproic acid label of January 24, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do clonazepam and valproic acid differ on the record?
In FDA's classes, clonazepam is a benzodiazepine and valproic acid a mood stabilizer.
Half-life, in each label's words: Clonazepam, “The elimination half-life of clonazepam is typically 30 to 40 hours.”; Valproic acid, “Mean terminal half-life for valproate monotherapy ranged from 9 to 16 hours following oral dosing regimens of 250 to …”
Both labels carry a boxed warning; the records quote them.
Generics: clonazepam since 1996; valproic acid since 1986 (Drugs@FDA).
DEA schedule: clonazepam CIV; valproic acid none.
| Clonazepam | Valproic acid | |
|---|---|---|
| Labeled for | Seizures and epilepsy, Anxiety | Seizures and epilepsy, Migraine |
| Pharmacologic class | Benzodiazepine | Anti-epileptic Agent, Mood Stabilizer |
| How it works (label) | n/a | Valproic acid dissociates to the valproate ion in the gastrointestinal tract. The mechanisms by which valproate exerts its therapeutic effects have not been established. |
| Half-life (label) | The elimination half-life of clonazepam is typically 30 to 40 hours. | Mean terminal half-life for valproate monotherapy ranged from 9 to 16 hours following oral dosing regimens of 250 to 1,000 mg. |
| Earliest approval on file (Drugs@FDA) | June 4, 1975 | February 28, 1978 |
| First generic approved | September 10, 1996 | February 28, 1986 |
| Generic labelers (NDC) | 31 labelers | 22 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0244 per tablet (Clonazepam 1 mg tablet) | $0.243 per capsule (Valproic acid 250 mg capsule) |
| 12-month price change | -14% | -4% |
| Boxed warning | Yes | Yes |
| Shortage now | In shortage | Listed; available |
| Recalls recorded | 7 | 2 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 159,283 | 51,380 |
| DEA schedule | CIV | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
Do their labels mention each other?
Valproic acid label, drug interactionsClonazepam The concomitant use of valproate and clonazepam may induce absence status in patients with a history of absence type seizures.
Source: FDA drug labels via openFDA
What next?
- Alternatives to clonazepam
- every medicine labeled for the same conditions