Two medicines, side by side
Clonazepam vs fluoxetine
Clonazepam and fluoxetine are both labeled for anxiety. Drugs@FDA records approvals of clonazepam since 1975 and of fluoxetine since 1987. Pharmacies paid $0.0244 per clonazepam 1 mg tablet and $0.0519 per fluoxetine HCl 40 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 fluoxetine a serotonin reuptake inhibitor.
Check it at the source: the clonazepam FDA label on DailyMed (effective December 1, 2025); the fluoxetine FDA label on DailyMed (effective January 8, 2026).
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 fluoxetine record
Fluoxetine (Prozac) · label of January 8, 2026
SUICIDAL THOUGHTS AND BEHAVIORS Antidepressants increased the risk of suicidal thoughts and behavior in children, adolescents, and young adults in short-term studies. These studies did not show an increase in the risk of suicidal thoughts and behavior with antidepressant use in patients over age 24; there was a reduction in risk with antidepressant use in patients aged 65 and older [see Warnings and Precautions ( 5.1 )].
Used for
From the label: indicationsPROZAC ® is indicated for the treatment of: Acute and maintenance treatment of Major Depressive Disorder [see Clinical Studies ( 14.1 )]. Acute and maintenance treatment of obsessions and compulsions in patients with Obsessive Compulsive Disorder (OCD) [see Clinical Studies ( 14.2 )]. […]
On the market
- Earliest approval on file
- December 29, 1987
- Generic labelers
- 58 labelers
- Pharmacy cost
- $0.0519 per capsule
Supply and safety
- Shortage
- No current entry
- Recalls
- 9
Source: FDA drug labels via openFDA (Clonazepam label of December 1, 2025, Fluoxetine label of January 8, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do clonazepam and fluoxetine differ on the record?
In FDA's classes, clonazepam is a benzodiazepine and fluoxetine a serotonin reuptake inhibitor.
Half-life, in each label's words: Clonazepam, “The elimination half-life of clonazepam is typically 30 to 40 hours.”; Fluoxetine, “Its mean terminal half-life after a single dose was 8.6 days and after multiple dosing was 9.3 days.”
Both labels carry a boxed warning; the records quote them.
Generics: clonazepam since 1996; fluoxetine since 2001 (Drugs@FDA).
DEA schedule: clonazepam CIV; fluoxetine none.
| Clonazepam | Fluoxetine | |
|---|---|---|
| Labeled for | Seizures and epilepsy, Anxiety | Depression, Anxiety, Bipolar disorder |
| Pharmacologic class | Benzodiazepine | Serotonin Reuptake Inhibitor |
| How it works (label) | n/a | Although the exact mechanism of PROZAC is unknown, it is presumed to be linked to its inhibition of CNS neuronal uptake of serotonin. |
| Half-life (label) | The elimination half-life of clonazepam is typically 30 to 40 hours. | Its mean terminal half-life after a single dose was 8.6 days and after multiple dosing was 9.3 days. |
| Earliest approval on file (Drugs@FDA) | June 4, 1975 | December 29, 1987 |
| First generic approved | September 10, 1996 | August 2, 2001 |
| Generic labelers (NDC) | 31 labelers | 58 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0244 per tablet (Clonazepam 1 mg tablet) | $0.0519 per capsule (Fluoxetine HCl 40 mg capsule) |
| 12-month price change | -14% | -20% |
| Boxed warning | Yes | Yes |
| Shortage now | In shortage | No current entry |
| Recalls recorded | 7 | 9 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 159,283 | 131,827 |
| 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?
Clonazepam label, drug interactionsThe selective serotonin reuptake inhibitors sertraline (weak CYP3A4 inducer) and fluoxetine (CYP2D6 inhibitor), and the anti-epileptic drug felbamate (CYP2C19 inhibitor and CYP3A4 inducer) do not affect the pharmacokinetics of clonazepam.
Source: FDA drug labels via openFDA
What do the labels say about using others of their kind?
Fluoxetine label, warnings and precautionsSerotonin syndrome has been reported with SSRIs and SNRIs, including PROZAC, both when taken alone, but especially when co-administered with other serotonergic agents.
Source: FDA drug labels via openFDA
What next?
- Alternatives to clonazepam
- every medicine labeled for the same conditions