Prescription medication · Benzodiazepine
clonazepam
Also sold as Klonopin. Clonazepam is used to treat certain seizure disorders, including Lennox-Gastaut syndrome, akinetic, and myoclonic seizures.
Data updated 2026-05-15
- 155,147
- FDA reportsHeavily reported
- 14
- InteractionsSeveral interactions
- 80% less
- Generic vs brandHuge savings
- In shortage
- FDA status
What the data shows
clonazepam (Klonopin) is a prescription Benzodiazepine, more reported than roughly 9 in 10 tracked drugs (155,147 FDA reports), whose generic runs roughly half the brand price or less (80% less).
Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.
clonazepam (Klonopin) is a prescription Benzodiazepine. Clonazepam is used to treat certain seizure disorders, including Lennox-Gastaut syndrome, akinetic, and myoclonic seizures.
Clonazepam is a medicine that belongs to the benzodiazepine class. It is used to treat seizure disorders and panic disorder.
Verify with FDA → · CMS NADAC pricing →
Drug Shortage Alert
clonazepam is currently listed as in shortage by the FDA. Affected manufacturer: Aurobindo Pharma USA. Status: Available.
View all drug shortages →Drug Pricing (NADAC)
Brand Price
$2.45/unit
Generic Price
$0.49/unit
Generic Savings
80%
Generic Available
Yes (9 manufacturers)
Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →
What it does
Clonazepam is used to treat certain seizure disorders, including Lennox-Gastaut syndrome, akinetic, and myoclonic seizures.
Common side effects
Drowsiness, Problems with coordination
Key warnings
Taking clonazepam with opioid medicines can cause very serious problems, including slowed breathing, coma, and death.
The sections below are summarized in plain English from clonazepam's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.
How It Works
Clonazepam works by affecting chemicals in your brain that may be unbalanced. It enhances the effects of a natural brain chemical called GABA. This helps to reduce seizures and relieve panic symptoms.
Side Effects (from patient reports)
Based on 155,147 FDA adverse event reports.
Most-reported reactions
Adverse reactions in FAERS for clonazepam, by number of reports
- Fatigue
Fatigue
10,236 reports
- Nausea
Nausea
9,564 reports
- Anxiety
Anxiety
8,735 reports
- Headache
Headache
8,590 reports
- Depression
Depression
8,121 reports
- Pain
Pain
8,033 reports
- Dizziness
Dizziness
7,245 reports
- Insomnia
Insomnia
7,008 reports
- Dyspnoea
Dyspnoea
6,826 reports
- Fall
Fall
6,625 reports
What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.
Reports over time
Adverse-event reports filed for clonazepam each year to the FDA Adverse Event Reporting System (FAERS).
Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.
Where clonazepam sits
clonazepam has more FDA adverse-event reports than 92% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.
Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is clonazepam; the line is the median (50th percentile).
FDA Adverse Event Report Analysis
Detailed analysis of 155,147 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2002–2025.
Total Reports
155,147
Reports Mentioning Death
18,179
11.7% of reports — not proof of cause
Hospitalization Reports
46,031
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 2 | FATIGUE | 10,236 |
| 3 | NAUSEA | 9,564 |
| 4 | ANXIETY | 8,735 |
| 5 | HEADACHE | 8,590 |
| 6 | DEPRESSION | 8,121 |
| 7 | PAIN | 8,033 |
| 9 | DIZZINESS | 7,245 |
| 10 | INSOMNIA | 7,008 |
| 11 | DYSPNOEA | 6,826 |
| 12 | FALL | 6,625 |
| 13 | DIARRHOEA | 6,606 |
| 14 | VOMITING | 6,214 |
| 15 | MALAISE | 5,976 |
| 16 | SOMNOLENCE | 5,590 |
| 17 | TOXICITY TO VARIOUS AGENTS | 5,182 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
Taking clonazepam with opioid medicines can cause very serious problems, including slowed breathing, coma, and death. Only take these medicines together if there are no other options. Clonazepam can be habit-forming, leading to abuse, misuse, and addiction, which can result in overdose or death. Stopping clonazepam suddenly can cause dangerous withdrawal symptoms. Your doctor will slowly lower your dose to prevent withdrawal.
Known Drug Interactions
The 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.
Mechanism: Sertraline does not interfere with how your body breaks down or uses clonazepam.
The 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.
Mechanism: Fluoxetine does not interfere with how your body breaks down or uses clonazepam.
The 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.
Mechanism: Felbamate does not change the levels of clonazepam in the body or how it is processed.
Although early studies reported an increased risk of congenital malformations with diazepam and chlordiazepoxide, there was no consistent pattern noted.
Mechanism: These drugs are both sedatives that slow down your brain and body. Taking them together can make you dangerously sleepy or cause trouble breathing.
Cytochrome P450 inducers, such as phenytoin, carbamazepine, lamotrigine, and phenobarbital induce clonazepam metabolism, causing an approximately 38% decrease in plasma clonazepam levels.
Mechanism: Lamotrigine speeds up the process of clearing clonazepam from your body. This results in lower levels of clonazepam in your bloodstream.
This is a plain-language summary of FDA-label interaction records and does not provide individual medication-combination directions.
Common Questions
Can I drink alcohol while taking clonazepam?
How long does it take for clonazepam to start working?
Can I drive while taking clonazepam?
What should I do if I feel like clonazepam is not working anymore?
Can I take other medications with clonazepam?
Is it safe to stop taking clonazepam suddenly?
What are the symptoms of clonazepam withdrawal?
Can clonazepam cause weight gain?
Does clonazepam interact with any foods?
What should I do if I overdose on clonazepam?
What are the common side effects of clonazepam?
Does clonazepam interact with other medications?
What drug class is clonazepam?
Is there a generic version of clonazepam?
What pregnancy or breastfeeding source fields are listed for clonazepam?
Has clonazepam been recalled?
Is clonazepam currently in shortage?
Active Recalls
Labeling: Label Error on Declared Strength; Some cartons were incorrectly labeled. The blister strips inside the product carton reflect the correct strength.
Endo USA, Inc.
Labeling: Label Error on Declared Strength; Some cartons were incorrectly labeled. The blister strips inside the product carton reflect the correct strength.
Endo USA, Inc.
Related Medications in Benzodiazepine
Other drugs grouped near clonazepam - same-class peers and common alternatives.
brivaracetam
Briviact
Brivaracetam is a medicine used to treat partial-onset seizures.
Compare with clonazepam →
cannabidiol
Epidiolex
Epidiolex is a medicine that contains cannabidiol.
Compare with clonazepam →
carbamazepine
Tegretol
Carbamazepine is a medicine used to control seizures and treat nerve pain.
Compare with clonazepam →
cenobamate
Xcopri
Xcopri is a medicine used to treat partial-onset seizures in adults.
Compare with clonazepam →
clobazam
Onfi, Sympazan
Clobazam oral suspension is a medicine used with other medicines to treat seizures caused by Lennox-Gastaut syndrome.
Compare with clonazepam →
Compare beyond drug class
Nationwide peers by FAERS volume & death-report share
Two PlainMeds-derived comparison paths for clonazepam: nearest FDA FAERS report volume and nearest death-report share among drugs with at least 1,000 logged reports, excluding same-class neighbors listed above. Counts reflect reporting volume, not proven individual harm.
Similar FAERS report volume
Nearest drugs by total FAERS reports. This record: 155,147.
Similar death-report share
Nearest drugs by FAERS death-report share. This record: 11.72%.
- propafenone Δ 0.03 pts · 4,113 reports · Class IC Antiarrhythmic 11.74%death share
- prazosin Δ 0.11 pts · 5,825 reports · Alpha-1 Blocker 11.61%death share
- rabeprazole Δ 0.14 pts · 21,352 reports · Proton Pump Inhibitor (PPI) 11.58%death share
- clonidine Δ 0.14 pts · 49,370 reports · Central Alpha-2 Agonist 11.86%death share
Medication Guides
Understanding Drug Interactions
How CYP450 enzymes, inhibitors, and inducers affect your medications
Generic vs Brand Name Drugs
FDA requirements, cost savings, and when the difference matters
Narrow Therapeutic Index Drugs
FDA bioequivalence and label-record context for narrow therapeutic index medicines
Common Drug Interactions
Dangerous medication combinations and how to protect yourself
Save on clonazepam
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What the FDA Data Shows for clonazepam
The FDA label for clonazepam (sold under brand names such as Klonopin) classifies it as a prescription-only medication in the Benzodiazepine class. Clonazepam is used to treat certain seizure disorders, including Lennox-Gastaut syndrome, akinetic, and myoclonic seizures. Official labeling lists 2 commonly reported side effects, including Drowsiness, Problems with coordination.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 155,147 voluntary reports. The database also lists 14 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated major severity. NADAC pricing from CMS shows a generic unit cost of $0.49 versus $2.45 for the brand - a 80% generic savings.
Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history (currently 2 recall records on file), and patent information are separate source-record fields. This page is a public FDA/CMS registry and does not provide medical, treatment, substitution, or medication-change directions.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC). Shortage status: FDA Drug Shortages Database.
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. This registry does not provide medication decisions.
Last updated: January 2, 2026
PlainMeds is rendered directly from FDA openFDA/FAERS extracts, DailyMed labels, and CMS drug-pricing files, no number is typed in by an editor. FAERS counts, recalls, shortages, and price figures on this page are queried live from those federal extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-15. Primary sources: openFDA / FAERS, DailyMed and CMS Part B ASP.
Read our methodology - how this data is sourced, computed, and verified.
Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled from the source snapshot dated . See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a data issue.
All federal data sources used on this page
- FDA Orange Book - approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed - NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) - post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm - standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files - federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database - current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages