PHENAZOPYRIDINE

72/100 · Elevated

Manufactured by Amneal Pharmaceuticals LLC

Phenazopyridine Adverse Events Highlight Chronic Kidney Disease and Renal Issues

9,031 FDA adverse event reports analyzed

Last updated: 2026-05-12

About PHENAZOPYRIDINE

PHENAZOPYRIDINE is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by Amneal Pharmaceuticals LLC. Based on analysis of 9,031 FDA adverse event reports, PHENAZOPYRIDINE 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 PHENAZOPYRIDINE include CHRONIC KIDNEY DISEASE, NAUSEA, PAIN, URINARY TRACT INFECTION, ACUTE KIDNEY INJURY. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for PHENAZOPYRIDINE.

AI Safety Analysis

Phenazopyridine 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 9,031 adverse event reports for this medication, which is primarily manufactured by Amneal Pharmaceuticals Llc.

The most commonly reported adverse events include Chronic Kidney Disease, Nausea, Pain. Of classified reports, 69.9% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Chronic kidney disease and acute kidney injury are among the most serious adverse reactions reported.

Renal failure and renal impairment are also frequently reported, indicating potential nephrotoxicity. The high volume of reports suggests a significant safety concern, especially for long-term use.

Patients taking Phenazopyridine should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Phenazopyridine should be used with caution in patients with pre-existing renal conditions, as it may exacerbate renal issues. Drug interactions, particularly with other nephrotoxic agents, should be monitored. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.

Safety Score: 72/100

Phenazopyridine received a safety concern score of 72/100 (elevated concern). This is based on a 69.9% serious event ratio across 3,596 classified reports. The score accounts for 9,031 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

CHRONIC KIDNEY DISEASE392 reports
NAUSEA296 reports
PAIN294 reports
URINARY TRACT INFECTION281 reports
ACUTE KIDNEY INJURY266 reports
FATIGUE257 reports
RENAL FAILURE253 reports
DIARRHOEA218 reports
ANXIETY182 reports
HEADACHE181 reports
VOMITING179 reports
OFF LABEL USE173 reports
DRUG HYPERSENSITIVITY142 reports
DIZZINESS138 reports
DEPRESSION136 reports
DRUG INEFFECTIVE134 reports
DYSPNOEA134 reports
FALL130 reports
CONSTIPATION120 reports
ARTHRALGIA115 reports
ASTHENIA115 reports
MALAISE111 reports
PAIN IN EXTREMITY110 reports
WEIGHT DECREASED106 reports
ABDOMINAL PAIN100 reports
EMOTIONAL DISTRESS100 reports
DYSURIA99 reports
DEATH98 reports
MUSCLE SPASMS94 reports
BACK PAIN93 reports
END STAGE RENAL DISEASE93 reports
HYPERTENSION89 reports
PYREXIA89 reports
GASTROOESOPHAGEAL REFLUX DISEASE85 reports
INJURY83 reports
ANAEMIA82 reports
PNEUMONIA82 reports
CONDITION AGGRAVATED81 reports
DECREASED APPETITE80 reports
CHEST PAIN78 reports
RASH78 reports
ALOPECIA73 reports
CYSTITIS73 reports
DEHYDRATION73 reports
METHAEMOGLOBINAEMIA73 reports
NEPHROLITHIASIS70 reports
PRURITUS70 reports
INSOMNIA68 reports
ABDOMINAL PAIN UPPER65 reports
FEELING ABNORMAL65 reports
ABDOMINAL DISCOMFORT63 reports
RENAL INJURY63 reports
HOT FLUSH62 reports
WEIGHT INCREASED62 reports
COUGH60 reports
MYALGIA58 reports
NEPHROGENIC ANAEMIA58 reports
PRODUCT DOSE OMISSION ISSUE58 reports
CONFUSIONAL STATE57 reports
HYPOAESTHESIA57 reports
HYPERHIDROSIS56 reports
SOMNOLENCE56 reports
DEEP VEIN THROMBOSIS53 reports
GAIT DISTURBANCE52 reports
MIGRAINE52 reports
SINUSITIS52 reports
HYPOTENSION51 reports
TREMOR51 reports
ANHEDONIA50 reports
OSTEOPOROSIS50 reports
TUBULOINTERSTITIAL NEPHRITIS50 reports
URINARY RETENTION50 reports
VISION BLURRED49 reports
BALANCE DISORDER48 reports
HYPERSENSITIVITY48 reports
POLLAKIURIA48 reports
COVID 1947 reports
PARAESTHESIA46 reports
PULMONARY EMBOLISM46 reports
NEUROPATHY PERIPHERAL45 reports
SEPSIS45 reports
DRUG DOSE OMISSION44 reports
MEMORY IMPAIRMENT44 reports
SULPHAEMOGLOBINAEMIA44 reports
ASTHMA43 reports
DYSPEPSIA43 reports
INFECTION43 reports
NASOPHARYNGITIS43 reports
BRONCHITIS42 reports
ABDOMINAL DISTENSION41 reports
CHILLS41 reports
CONTUSION41 reports
PALPITATIONS41 reports
RENAL IMPAIRMENT41 reports
URTICARIA41 reports
BLOOD PRESSURE INCREASED40 reports
MUSCULAR WEAKNESS40 reports
MYOCARDIAL INFARCTION40 reports
TOXICITY TO VARIOUS AGENTS40 reports
CEREBROVASCULAR ACCIDENT39 reports

Key Safety Signals

  • Chronic kidney disease and acute kidney injury
  • Renal failure and renal impairment
  • High volume of reports and diverse reactions

Patient Demographics

Adverse event reports by sex: Female: 2,564, Male: 811, Unknown: 5. The most frequently reported age groups are age 67 (65 reports), age 64 (63 reports), age 66 (63 reports). These demographics reflect reporting patterns and may not represent the full patient population.

Report Outcomes

Out of 3,596 classified reports for PHENAZOPYRIDINE:

  • Serious: 2,513 reports (69.9%) — includes hospitalization, disability, life-threatening events, or death
  • Non-Serious: 1,083 reports (30.1%)
Serious 69.9%Non-Serious 30.1%

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

Female2,564 (75.9%)
Male811 (24.0%)
Unknown5 (0.1%)

Reports by Age

Age 6765 reports
Age 6463 reports
Age 6663 reports
Age 6261 reports
Age 5958 reports
Age 6857 reports
Age 5253 reports
Age 6553 reports
Age 5552 reports
Age 6048 reports
Age 5747 reports
Age 7147 reports
Age 3746 reports
Age 4344 reports
Age 5844 reports
Age 6144 reports
Age 5143 reports
Age 5643 reports
Age 7443 reports
Age 7042 reports

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

Drug Interactions & Warnings

Phenazopyridine should be used with caution in patients with pre-existing renal conditions, as it may exacerbate renal issues. Drug interactions, particularly with other nephrotoxic agents, should be monitored.

What You Should Know

If you are taking Phenazopyridine, here are important things to know. The most commonly reported side effects include chronic kidney disease, nausea, pain, urinary tract infection, acute kidney injury. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Patients should avoid long-term use of phenazopyridine and seek medical advice if they experience symptoms of kidney issues such as decreased urine output, swelling, or pain in the abdomen. Consumers should report any adverse reactions to the FDA's MedWatch program to help improve safety monitoring. 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

The FDA has issued warnings regarding the potential for renal toxicity with phenazopyridine. Healthcare providers should regularly monitor renal function in patients taking this medication, especially those with pre-existing renal conditions.

Frequently Asked Questions

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

The FDA has received approximately 9,031 adverse event reports associated with Phenazopyridine. 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 Phenazopyridine?

The most frequently reported adverse events for Phenazopyridine include Chronic Kidney Disease, Nausea, Pain, Urinary Tract Infection, Acute Kidney Injury. By volume, the top reported reactions are: Chronic Kidney Disease (392 reports), Nausea (296 reports), Pain (294 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Phenazopyridine.

What percentage of Phenazopyridine adverse event reports are serious?

Out of 3,596 classified reports, 2,513 (69.9%) were classified as serious and 1,083 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 Phenazopyridine (by sex)?

Adverse event reports for Phenazopyridine break down by patient sex as follows: Female: 2,564, Male: 811, Unknown: 5. 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 Phenazopyridine?

The most frequently reported age groups for Phenazopyridine adverse events are: age 67: 65 reports, age 64: 63 reports, age 66: 63 reports, age 62: 61 reports, age 59: 58 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 Phenazopyridine?

The primary manufacturer associated with Phenazopyridine adverse event reports is Amneal Pharmaceuticals 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 Phenazopyridine?

Beyond the most common reactions, other reported adverse events for Phenazopyridine include: Fatigue, Renal Failure, Diarrhoea, Anxiety, Headache. 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 Phenazopyridine?

You can report adverse events from Phenazopyridine 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 Phenazopyridine's safety score and what does it mean?

Phenazopyridine 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. Chronic kidney disease and acute kidney injury are among the most serious adverse reactions reported.

What are the key safety signals for Phenazopyridine?

Key safety signals identified in Phenazopyridine's adverse event data include: Chronic kidney disease and acute kidney injury. Renal failure and renal impairment. High volume of reports and diverse reactions. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.

Does Phenazopyridine interact with other drugs?

Phenazopyridine should be used with caution in patients with pre-existing renal conditions, as it may exacerbate renal issues. Drug interactions, particularly with other nephrotoxic agents, should be monitored. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Phenazopyridine.

What should patients know before taking Phenazopyridine?

Patients should avoid long-term use of phenazopyridine and seek medical advice if they experience symptoms of kidney issues such as decreased urine output, swelling, or pain in the abdomen. Consumers should report any adverse reactions to the FDA's MedWatch program to help improve safety monitoring.

Are Phenazopyridine side effects well-documented?

Phenazopyridine has 9,031 adverse event reports on file with the FDA. Renal failure and renal impairment are also frequently reported, indicating potential nephrotoxicity. The volume of reports for Phenazopyridine reflects both the drug's usage level and the vigilance of the reporting community.

What is the FDA's position on Phenazopyridine?

The FDA has issued warnings regarding the potential for renal toxicity with phenazopyridine. Healthcare providers should regularly monitor renal function in patients taking this medication, especially those with pre-existing renal conditions. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.

Related Drugs

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

AmoxicillinCiprofloxacinNitrofurantoinSulfamethoxazoleTrimethoprim
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.