PRIMIDONE

72/100 · Elevated

Manufactured by Bausch Health US, LLC

Primidone Adverse Events: High Incidence of Neurological and Gastrointestinal Issues

19,417 FDA adverse event reports analyzed

Last updated: 2026-05-12

About PRIMIDONE

PRIMIDONE is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by Bausch Health US, LLC. Based on analysis of 19,417 FDA adverse event reports, PRIMIDONE has a safety score of 72 out of 100. This score indicates a relatively favorable safety profile, with fewer or less severe adverse events compared to many other tracked medications. The most commonly reported adverse reactions for PRIMIDONE include DRUG INEFFECTIVE, FALL, FATIGUE, TREMOR, DIZZINESS. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for PRIMIDONE.

AI Safety Analysis

Primidone has a safety concern score of 72 out of 100, placing it in the elevated concern category based on analysis of FDA adverse event data. The FDA has received approximately 19,417 adverse event reports for this medication, which is primarily manufactured by Bausch Health Us, Llc.

The most commonly reported adverse events include Drug Ineffective, Fall, Fatigue. Of classified reports, 65.8% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Primidone reports show a high incidence of neurological issues such as falls, tremors, and seizures.

Gastrointestinal symptoms like diarrhea, nausea, and vomiting are also frequently reported. Serious adverse events, including death and pneumonia, account for a significant portion of reports.

Patients taking Primidone should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Primidone can cause drug interactions, and patients should be warned about potential interactions with other medications. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.

Safety Score: 72/100

Primidone received a safety concern score of 72/100 (elevated concern). This is based on a 65.8% serious event ratio across 9,782 classified reports. The score accounts for 19,417 total adverse event reports and 100 distinct reaction types. This elevated score indicates a notable proportion of serious adverse events and warrants careful monitoring.

Top Adverse Reactions

DRUG INEFFECTIVE815 reports
FALL651 reports
FATIGUE616 reports
TREMOR569 reports
DIZZINESS484 reports
DIARRHOEA480 reports
OFF LABEL USE475 reports
NAUSEA458 reports
HEADACHE385 reports
DRUG INTERACTION378 reports
SOMNOLENCE377 reports
ASTHENIA353 reports
DYSPNOEA350 reports
WEIGHT DECREASED323 reports
PAIN318 reports
PNEUMONIA296 reports
DEATH290 reports
GAIT DISTURBANCE285 reports
SEIZURE265 reports
CONDITION AGGRAVATED262 reports
MALAISE260 reports
VOMITING255 reports
CONVULSION250 reports
PRURITUS240 reports
RASH228 reports
CONSTIPATION225 reports
COUGH225 reports
DEPRESSION224 reports
ARTHRALGIA220 reports
BALANCE DISORDER215 reports
BACK PAIN213 reports
URINARY TRACT INFECTION212 reports
INSOMNIA211 reports
FEELING ABNORMAL208 reports
PAIN IN EXTREMITY205 reports
CONFUSIONAL STATE199 reports
ANXIETY197 reports
MEMORY IMPAIRMENT184 reports
WEIGHT INCREASED177 reports
TOXICITY TO VARIOUS AGENTS169 reports
HYPERTENSION166 reports
COMPLETED SUICIDE163 reports
PYREXIA162 reports
OEDEMA PERIPHERAL159 reports
PRODUCT DOSE OMISSION ISSUE159 reports
LOSS OF CONSCIOUSNESS158 reports
PRODUCT USE ISSUE154 reports
ABDOMINAL PAIN150 reports
RENAL FAILURE150 reports
PRODUCT USE IN UNAPPROVED INDICATION147 reports
DECREASED APPETITE146 reports
BLOOD PRESSURE INCREASED142 reports
HYPOTENSION140 reports
CHEST PAIN134 reports
HALLUCINATION131 reports
MUSCLE SPASMS129 reports
DRUG HYPERSENSITIVITY128 reports
MUSCULAR WEAKNESS127 reports
CONTUSION125 reports
ANAEMIA120 reports
HYPOAESTHESIA118 reports
ABDOMINAL PAIN UPPER117 reports
CHRONIC KIDNEY DISEASE117 reports
VISION BLURRED117 reports
DEHYDRATION116 reports
CEREBROVASCULAR ACCIDENT112 reports
OVERDOSE109 reports
DYSPHAGIA108 reports
ALOPECIA107 reports
COVID 19106 reports
NEUROPATHY PERIPHERAL102 reports
AMNESIA101 reports
BLOOD GLUCOSE INCREASED98 reports
HYPERSENSITIVITY98 reports
PERIPHERAL SWELLING98 reports
ATRIAL FIBRILLATION96 reports
SINUSITIS96 reports
ATAXIA94 reports
VISUAL IMPAIRMENT93 reports
INFLUENZA92 reports
MULTIPLE SCLEROSIS RELAPSE92 reports
PARAESTHESIA92 reports
ABDOMINAL DISCOMFORT91 reports
INJECTION SITE PAIN89 reports
MIGRAINE89 reports
STRESS88 reports
ACUTE KIDNEY INJURY87 reports
CARDIAC FAILURE CONGESTIVE86 reports
EPILEPSY85 reports
NASOPHARYNGITIS85 reports
ASTHMA84 reports
BRONCHITIS82 reports
DYSARTHRIA81 reports
HYPERHIDROSIS81 reports
MYOCARDIAL INFARCTION80 reports
ARTHRITIS79 reports
MULTIPLE SCLEROSIS79 reports
MYALGIA79 reports
AGITATION78 reports
CHRONIC OBSTRUCTIVE PULMONARY DISEASE78 reports

Key Safety Signals

  • Falls and dizziness are common, indicating potential risk of injury.
  • Seizures and convulsions are reported, suggesting a risk for patients with epilepsy.
  • Death and pneumonia are serious adverse events that require close monitoring.

Patient Demographics

Adverse event reports by sex: Female: 5,515, Male: 3,638, Unknown: 20. The most frequently reported age groups are age 70 (217 reports), age 72 (199 reports), age 71 (198 reports). These demographics reflect reporting patterns and may not represent the full patient population.

Report Outcomes

Out of 9,782 classified reports for PRIMIDONE:

  • Serious: 6,435 reports (65.8%) — includes hospitalization, disability, life-threatening events, or death
  • Non-Serious: 3,347 reports (34.2%)
Serious 65.8%Non-Serious 34.2%

The FDA classifies an adverse event as “serious” if it results in death, hospitalization, disability, congenital anomaly, or requires intervention to prevent permanent damage.

Demographics Breakdown

Reports by Sex

Female5,515 (60.1%)
Male3,638 (39.7%)
Unknown20 (0.2%)

Reports by Age

Age 70217 reports
Age 72199 reports
Age 71198 reports
Age 69196 reports
Age 77188 reports
Age 64187 reports
Age 74185 reports
Age 75181 reports
Age 76176 reports
Age 78175 reports
Age 67163 reports
Age 68163 reports
Age 73159 reports
Age 65153 reports
Age 66153 reports
Age 63150 reports
Age 60147 reports
Age 79140 reports
Age 62139 reports
Age 61132 reports

Demographics reflect voluntary FDA adverse event reporting patterns and may not represent the full patient population.

Drug Interactions & Warnings

Primidone can cause drug interactions, and patients should be warned about potential interactions with other medications.

What You Should Know

If you are taking Primidone, here are important things to know. The most commonly reported side effects include drug ineffective, fall, fatigue, tremor, dizziness. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Monitor patients for signs of neurological issues and adjust dosing as necessary. Inform patients about the risk of falls and dizziness and advise them to avoid activities that could be dangerous. Closely monitor patients with pre-existing conditions such as epilepsy or respiratory issues. If you experience a serious adverse reaction, seek emergency medical attention immediately or call 911. You can report side effects to the FDA's MedWatch program at 1-800-FDA-1088.

Regulatory Context

Primidone is subject to FDA oversight, and patients should report any adverse events to their healthcare provider.

Frequently Asked Questions

How many adverse event reports has the FDA received for Primidone?

The FDA has received approximately 19,417 adverse event reports associated with Primidone. These reports come from healthcare professionals, consumers, and manufacturers through the FDA Adverse Event Reporting System (FAERS). Note that the number of reports does not directly indicate the frequency of side effects, as adverse events are voluntarily reported and may be underrepresented.

What are the most commonly reported side effects of Primidone?

The most frequently reported adverse events for Primidone include Drug Ineffective, Fall, Fatigue, Tremor, Dizziness. By volume, the top reported reactions are: Drug Ineffective (815 reports), Fall (651 reports), Fatigue (616 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Primidone.

What percentage of Primidone adverse event reports are serious?

Out of 9,782 classified reports, 6,435 (65.8%) were classified as serious and 3,347 as non-serious. The FDA classifies an event as "serious" if it results in death, hospitalization, disability, or other medically significant outcomes. A higher serious-event ratio warrants closer attention but does not necessarily mean the drug is unsafe.

Who reports adverse events for Primidone (by sex)?

Adverse event reports for Primidone break down by patient sex as follows: Female: 5,515, Male: 3,638, Unknown: 20. This distribution reflects reporting patterns rather than actual risk differences between groups. Reporting rates can be influenced by prescribing patterns, disease demographics, and reporting behavior.

What age groups report the most side effects for Primidone?

The most frequently reported age groups for Primidone adverse events are: age 70: 217 reports, age 72: 199 reports, age 71: 198 reports, age 69: 196 reports, age 77: 188 reports. Age-related reporting patterns can reflect both the demographics of the patient population and potential age-related susceptibility to certain side effects.

Who manufactures Primidone?

The primary manufacturer associated with Primidone adverse event reports is Bausch Health Us, Llc. Multiple manufacturers may produce generic versions of this drug. The manufacturer listed reflects the most frequently reported brand in FDA adverse event data.

What other side effects have been reported for Primidone?

Beyond the most common reactions, other reported adverse events for Primidone include: Diarrhoea, Off Label Use, Nausea, Headache, Drug Interaction. Less common side effects can still be clinically significant. Patients should report any unusual symptoms to their healthcare provider.

How do I report a side effect from Primidone?

You can report adverse events from Primidone to the FDA through their MedWatch program at www.fda.gov/medwatch, by calling 1-800-FDA-1088, or by completing Form FDA 3500. Healthcare professionals, consumers, and manufacturers can all submit reports. Reporting helps the FDA monitor drug safety after approval.

What is Primidone's safety score and what does it mean?

Primidone has a safety concern score of 72 out of 100 (elevated concern). This score is calculated from the ratio of serious to non-serious adverse events, the diversity of reported reactions, and the overall volume of reports relative to usage. Primidone reports show a high incidence of neurological issues such as falls, tremors, and seizures.

What are the key safety signals for Primidone?

Key safety signals identified in Primidone's adverse event data include: Falls and dizziness are common, indicating potential risk of injury.. Seizures and convulsions are reported, suggesting a risk for patients with epilepsy.. Death and pneumonia are serious adverse events that require close monitoring.. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.

Does Primidone interact with other drugs?

Primidone can cause drug interactions, and patients should be warned about potential interactions with other medications. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Primidone.

What should patients know before taking Primidone?

Monitor patients for signs of neurological issues and adjust dosing as necessary. Inform patients about the risk of falls and dizziness and advise them to avoid activities that could be dangerous. Closely monitor patients with pre-existing conditions such as epilepsy or respiratory issues.

Are Primidone side effects well-documented?

Primidone has 19,417 adverse event reports on file with the FDA. Gastrointestinal symptoms like diarrhea, nausea, and vomiting are also frequently reported. The volume of reports for Primidone reflects both the drug's usage level and the vigilance of the reporting community.

What is the FDA's position on Primidone?

Primidone is subject to FDA oversight, and patients should report any adverse events to their healthcare provider. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.

Related Drugs

Drugs related to PRIMIDONE based on therapeutic use, drug class, or shared indications:

CarbamazepinePhenytoinValproic acidLamotrigineGabapentin
Important Disclaimer: This content is generated by AI analysis of FDA adverse event reports and is provided for informational purposes only. It is not medical advice. Adverse event reports submitted to the FDA do not prove that a medication caused the reported side effect. Always consult your healthcare provider before starting, stopping, or changing any medication. If you experience a serious side effect, contact your doctor or call 911 immediately.