Phenazopyridine 100mg tablets
Prescription only
Requires a prescription from a doctor or prescriber
Tablet
100mg
Oral
Phenazopyridine, also known as Pyridium, is a urinary tract analgesic used for the short-term management of urinary tract irritation and its associated unpleasant symptoms such as burning and pain during urination.
Active ingredients:
Phenazopyridine
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Safety monitoring data
Yellow Card reports
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The MHRA Yellow Card scheme collects reports of suspected side effects from healthcare professionals and patients. View the Drug Analysis Profile (iDAP) for real-world adverse reaction data.
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Similarity based on WHO Anatomical Therapeutic Chemical (ATC) classification and NHS BNF section grouping. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
Clinical guidelines and formulary information
British National Formulary
Phenazopyridine
BNF
Drug monograph — bnf.nice.org.ukSource: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.
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SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF codes from NHS Business Services Authority (NHSBSA). ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).
Active and completed clinical studies from ClinicalTrials.gov
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Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
196 found
Half-life
7.35 hours
Mechanism
The full mechanism of action of phenazopyridine is not fully elucidated[L7844],…
Food interactions
1 warning
Human targets
1 target
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
29.23 ng/mL
Phenazopyridine is absorbed in the gastrointestinal tract.
[A182159][L7850]
The mean Cmax is 65.00…
[A182159][L7850]
The mean Cmax is 65.00…
Half-life
7.35 hours
The mean elimination half-life of phenazopyridine is 7.35 hours in rats with healthy renal function.
[A182174]…
[A182174]…
Volume of distribution
Small, trace quantities of phenazopyridine are thought to cross the placenta and the blood-brain barrier, reaching cerebrospinal fluid.
[L7829]…
[L7829]…
Metabolism
48.3%
Phenazopyridine is metabolized in the liver, and acetaminophen has been discovered to be one metabolite of this drug.
[L7829]…
[L7829]…
Elimination
65%
Up to 65% of an oral phenazopyridine dose is quickly excreted by the kidneys as unchanged drug measured in the urine.
[L7829]
The…
[L7829]
The…
Clearance
65%
This drug is rapidly excreted by the kidneys, up to 65% of a dose administered orally may be excreted as unchanged drug in the urine.…
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Status:
Approved
Small molecule
About this compound
Phenazopyridine, also known as Pyridium, is a urinary tract analgesic used for the short-term management of urinary tract irritation and its associated unpleasant symptoms such as burning and pain during urination. In the USA, this drug was previously marked by Roche but has been discontinued by the FDA.[L7832] It is still used in various parts of the world. Ingestion of phenazopyridine is found to change the appearance of the urine by imparting an orange or red color, as it is considered an azo dye.[L7829]
Properties:
solid
Avg. mass: 213.24 Da
DrugBank indication
Phenazopyridine hydrochloride is indicated to relieve uncomfortable symptoms that occur as a consequence of mucosal irritation of the lower urinary tract in adults. The irritation may be a result of trauma, surgery, endoscopic procedures, infection, or the insertion of instruments or urinary catheters.
[L7826]
Phenazopyridine may be used in combination with antimicrobial therapy but is not used as an antimicrobial agent. It contributes to the relief of discomfort and pain before antimicrobial therapy begins to take effect. It is important to note that the duration of treatment with this drug should last a maximum of 2 days.
[L7826]
Phenazopyridine is available in many countries as an over the counter drug.
[A182147]
[L7826]
Phenazopyridine may be used in combination with antimicrobial therapy but is not used as an antimicrobial agent. It contributes to the relief of discomfort and pain before antimicrobial therapy begins to take effect. It is important to note that the duration of treatment with this drug should last a maximum of 2 days.
[L7826]
Phenazopyridine is available in many countries as an over the counter drug.
[A182147]
Also known as(12)
2,6-Diamino-3-(phenylazo)pyridine
2,6-Diamino-3-phenylazopyridine
3-(Phenylazo)-2,6-pyridinediamine
Fenazopiridina
Phenazopyridine
Phénazopyridine
Phenazopyridinum
NAC1
Dosage forms(32)
Kit; tablet (Oral)
Tablet (Oral) — 100.0 mg
Tablet (Oral) — 95 mg/1
Tablet; tablet, film coated (Oral) — 100 MG
Tablet (Oral) — 100 mg/1
Tablet (Oral) — 100 mg/1mg
Tablet (Oral) — 200 mg/1mg
Tablet (Oral) — 200 mg/1
Molecular properties(19)
Drug interactions(764)
Known interactions with other medications. Always consult a healthcare professional.
Prilocaine
Unknown severity
The risk or severity of methemoglobinemia can be increased when Phenazopyridine is combined with Prilocaine.
The risk or severity of nephrotoxicity can be increased when Phenazopyridine is combined with Foscarnet.
The risk or severity of nephrotoxicity can be increased when Mannitol is combined with Phenazopyridine.
Tenofovir disoproxil
Moderate
Phenazopyridine may increase the nephrotoxic activities of Tenofovir disoproxil.
Tenofovir alafenamide
Unknown severity
The serum concentration of Tenofovir alafenamide can be increased when it is combined with Phenazopyridine.
Phenazopyridine may increase the nephrotoxic activities of Tenofovir.
The risk or severity of methemoglobinemia can be increased when Dapsone is combined with Phenazopyridine.
Cyclosporine
Major
The risk or severity of nephrotoxicity can be increased when Cyclosporine is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Icosapent is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Cefotiam is combined with Phenazopyridine.
Mesalazine
Major
The risk or severity of nephrotoxicity can be increased when Mesalazine is combined with Phenazopyridine.
Cefmenoxime
Major
The risk or severity of nephrotoxicity can be increased when Cefmenoxime is combined with Phenazopyridine.
Cefmetazole
Major
The risk or severity of nephrotoxicity can be increased when Cefmetazole is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Pamidronic acid is combined with Phenazopyridine.
Indomethacin
Major
The risk or severity of nephrotoxicity can be increased when Indomethacin is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Cidofovir is combined with Phenazopyridine.
Triamterene
Major
The risk or severity of nephrotoxicity can be increased when Triamterene is combined with Phenazopyridine.
Cefpiramide
Major
The risk or severity of nephrotoxicity can be increased when Cefpiramide is combined with Phenazopyridine.
Ceftazidime
Major
The risk or severity of nephrotoxicity can be increased when Ceftazidime is combined with Phenazopyridine.
Loracarbef
Major
The risk or severity of nephrotoxicity can be increased when Loracarbef is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Cefalotin is combined with Phenazopyridine.
Nabumetone
Major
The risk or severity of nephrotoxicity can be increased when Nabumetone is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Ketorolac is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Tenoxicam is combined with Phenazopyridine.
Cefotaxime
Major
The risk or severity of nephrotoxicity can be increased when Cefotaxime is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Tolmetin is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Rofecoxib is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Piroxicam is combined with Phenazopyridine.
Methotrexate
Major
The risk or severity of nephrotoxicity can be increased when Methotrexate is combined with Phenazopyridine.
Cephalexin
Major
The risk or severity of nephrotoxicity can be increased when Cephalexin is combined with Phenazopyridine.
Fenoprofen
Major
The risk or severity of nephrotoxicity can be increased when Fenoprofen is combined with Phenazopyridine.
Valaciclovir
Major
The risk or severity of nephrotoxicity can be increased when Valaciclovir is combined with Phenazopyridine.
Valdecoxib
Major
The risk or severity of nephrotoxicity can be increased when Valdecoxib is combined with Phenazopyridine.
Diclofenac
Major
The risk or severity of nephrotoxicity can be increased when Diclofenac is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Sulindac is combined with Phenazopyridine.
Bacitracin
Major
The risk or severity of nephrotoxicity can be increased when Bacitracin is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Amphotericin B is combined with Phenazopyridine.
Cephaloglycin
Major
The risk or severity of nephrotoxicity can be increased when Cephaloglycin is combined with Phenazopyridine.
Furosemide
Major
The risk or severity of nephrotoxicity can be increased when Furosemide is combined with Phenazopyridine.
Flurbiprofen
Major
The risk or severity of nephrotoxicity can be increased when Flurbiprofen is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Adefovir dipivoxil is combined with Phenazopyridine.
Pentamidine
Major
The risk or severity of nephrotoxicity can be increased when Pentamidine is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Etodolac is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Mefenamic acid is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Acyclovir is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Naproxen is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Phenylbutazone is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Meloxicam is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Carprofen is combined with Phenazopyridine.
The risk or severity of nephrotoxicity can be increased when Cefaclor is combined with Phenazopyridine.
Showing 50 of 764 interactions
Food & lifestyle interactions
Take With Food
Take with food. Food reduces irritation.
Toxicity & overdose
The oral LD50 of phenazopyridine in rats is 472 mg/kg.
[L7847]
Overdose information
Administering excess phenazopyridine above the daily recommended dose in those with healthy or impaired kidney function may increase the drug concentration and predispose the patient to toxicity. When a large overdose occurs, methemoglobinemia results.
[A182141][A182144]
To treat this condition, Methylene blue at 1 to 2 mg/kg/dose should be administered intravenously as a 1% solution as deemed necessary. Its administration is likely to cause a rapid reduction of the methemoglobinemia state and relieve the associated cyanosis.
Hemolytic anemia is also a risk when an overdose occurs, and “bite cells” may be observed in a blood smear after an overdose with phenazopyridine. Red blood cell G6PD deficiency may increase the risk of hemolysis, and even normal doses can lead to methemoglobinemia in patients with this condition. Nephrotoxicity, renal failure, and hepatic impairment may also occur in a case of overdose with this drug.
Administer symptomatic and supportive treatment as necessary.
[A182138][A182147][L7844]
[L7847]
Overdose information
Administering excess phenazopyridine above the daily recommended dose in those with healthy or impaired kidney function may increase the drug concentration and predispose the patient to toxicity. When a large overdose occurs, methemoglobinemia results.
[A182141][A182144]
To treat this condition, Methylene blue at 1 to 2 mg/kg/dose should be administered intravenously as a 1% solution as deemed necessary. Its administration is likely to cause a rapid reduction of the methemoglobinemia state and relieve the associated cyanosis.
Hemolytic anemia is also a risk when an overdose occurs, and “bite cells” may be observed in a blood smear after an overdose with phenazopyridine. Red blood cell G6PD deficiency may increase the risk of hemolysis, and even normal doses can lead to methemoglobinemia in patients with this condition. Nephrotoxicity, renal failure, and hepatic impairment may also occur in a case of overdose with this drug.
Administer symptomatic and supportive treatment as necessary.
[A182138][A182147][L7844]
How it works
Mechanism of action
The full mechanism of action of phenazopyridine is not fully elucidated[L7844], however, it is reported to exert a direct topical analgesic effect on the mucosal lining of the urinary tract via the inhibition of voltage-gated sodium channels[L7841] and possibly group A nerve fibers, as suggested by the results of a study in rats.[A17018] The above actions likely lead to the relief of unpleasant urinary symptoms.[L7829]
Pharmacodynamics
Phenazopyridine acts as a local anesthetic offering relief from irritating conditions of the urinary tract. It relieves urinary urgency frequency, burning, pain, and discomfort.[L7826][L7844]
A note on urine and skin discoloration and interference with test results
Yellowing of the skin or sclerae of the eyes may indicate that the accumulation of phenazopyridine has occurred. This may be a consequence of overdose, decreased renal function, taking the drug for over two days. Elderly patients may be at particular risk due to a decline in renal function, potentiating the risk of phenazopyridine accumulation. The drug should be discontinued if yellowing of the skin or sclerae is observed.[L7826] Hemolytic anemia is a risk of phenazopyridine, especially in cases of overdose. In addition to the above effects, this drug may impart an orange or red color of urine and feces, causing staining of clothing. Other body fluids may also be stained, and in patients wearing contact lenses, phenazopyridine may cause lens staining. Due to its orange-red color, this drug may interfere with laboratory requiring colorimetric, spectrophotometric or fluorometric methods of analysis.[L7826] In patients with G6PD enzyme deficiency, this drug poses a greater risk of hemolysis, even at normal doses and is not recommended.[L7826]
A note on carcinogenesis
Based on the results of in vivo studies in rats, this drug has been listed as a carcinogen in the USA since 1981. Rats given this drug were found to demonstrate increased rates of hepatocellular carcinoma and colorectal tumors.[L7871] Use this agent with caution and limit the administration of this drug when possible.
A note on urine and skin discoloration and interference with test results
Yellowing of the skin or sclerae of the eyes may indicate that the accumulation of phenazopyridine has occurred. This may be a consequence of overdose, decreased renal function, taking the drug for over two days. Elderly patients may be at particular risk due to a decline in renal function, potentiating the risk of phenazopyridine accumulation. The drug should be discontinued if yellowing of the skin or sclerae is observed.[L7826] Hemolytic anemia is a risk of phenazopyridine, especially in cases of overdose. In addition to the above effects, this drug may impart an orange or red color of urine and feces, causing staining of clothing. Other body fluids may also be stained, and in patients wearing contact lenses, phenazopyridine may cause lens staining. Due to its orange-red color, this drug may interfere with laboratory requiring colorimetric, spectrophotometric or fluorometric methods of analysis.[L7826] In patients with G6PD enzyme deficiency, this drug poses a greater risk of hemolysis, even at normal doses and is not recommended.[L7826]
A note on carcinogenesis
Based on the results of in vivo studies in rats, this drug has been listed as a carcinogen in the USA since 1981. Rats given this drug were found to demonstrate increased rates of hepatocellular carcinoma and colorectal tumors.[L7871] Use this agent with caution and limit the administration of this drug when possible.
Pharmacokinetics
How the body processes this drug — absorption, distribution, metabolism, and elimination
Absorption
Phenazopyridine is absorbed in the gastrointestinal tract.
[A182159][L7850]
The mean Cmax is 65.00 ± 29.23 ng/mL, the mean Tmax is 2.48 ± 0.50 h, and the mean AUC(0 – ∞)is 431.77 ± 87.82 ng.h/mL.
[A182171]
[A182159][L7850]
The mean Cmax is 65.00 ± 29.23 ng/mL, the mean Tmax is 2.48 ± 0.50 h, and the mean AUC(0 – ∞)is 431.77 ± 87.82 ng.h/mL.
[A182171]
Half-life
The mean elimination half-life of phenazopyridine is 7.35 hours in rats with healthy renal function.
[A182174]
The half-life in man is not readily vailable in the literature.
[A182174]
The half-life in man is not readily vailable in the literature.
Volume of distribution
Small, trace quantities of phenazopyridine are thought to cross the placenta and the blood-brain barrier, reaching cerebrospinal fluid.
[L7829]
A pharmacokinetic study in rats determined that phenazopyridine metabolites were present in high levels in the kidney and liver.
[A182174]
[L7829]
A pharmacokinetic study in rats determined that phenazopyridine metabolites were present in high levels in the kidney and liver.
[A182174]
Metabolism
Phenazopyridine is metabolized in the liver, and acetaminophen has been discovered to be one metabolite of this drug.
[L7829]
Hydroxylation is a pathway by which this drug is metabolized.
[A182180]
In humans, 5-hydroxyl PAP is the major metabolite (48.3% of the dose) and small amounts of other hydroxy metabolites are produced.
[A182171][L7865]
The metabolism of phenazopyridine produces aniline, which is likely associated with methemoglobinemia in some patients or in the case of an overdose. This dye accumulates in the skin, and yellow skin pigmentation has been observed when high doses of this drug have been taken.
[L7826]
Triaminopyridine is also a metabolite of phenazopyridine.
[L7865]
During a pharmacokinetic study, aniline contributed to approximately 6.9% of urinary metabolites. N acetyl-p-aminophenol (acetaminophen) contributes to about 18%, P-aminophenol (PAP) contributes 24%, and finally, DPP (unchanged phenazopyridine) contributes to about 41% of excreted urinary metabolites.
[A182159]
[L7829]
Hydroxylation is a pathway by which this drug is metabolized.
[A182180]
In humans, 5-hydroxyl PAP is the major metabolite (48.3% of the dose) and small amounts of other hydroxy metabolites are produced.
[A182171][L7865]
The metabolism of phenazopyridine produces aniline, which is likely associated with methemoglobinemia in some patients or in the case of an overdose. This dye accumulates in the skin, and yellow skin pigmentation has been observed when high doses of this drug have been taken.
[L7826]
Triaminopyridine is also a metabolite of phenazopyridine.
[L7865]
During a pharmacokinetic study, aniline contributed to approximately 6.9% of urinary metabolites. N acetyl-p-aminophenol (acetaminophen) contributes to about 18%, P-aminophenol (PAP) contributes 24%, and finally, DPP (unchanged phenazopyridine) contributes to about 41% of excreted urinary metabolites.
[A182159]
Route of elimination
Up to 65% of an oral phenazopyridine dose is quickly excreted by the kidneys as unchanged drug measured in the urine.
[L7829]
The pharmacokinetics of this drug have not been evaluated in depth in man. In a small group of healthy research volunteers, 90% of a daily 600 mg oral dose of phenazopyridine hydrochloride was found to be excreted within 1 day, with 41% as unchanged drug and 49% as phenazopyridine metabolites.
[L7826]
Another study in humans determined that 80.07 ± 4.54 percent of the dose was cleared in the urine within 48 hours of administration.
[A182156]
In rats, biliary excretion was high, with 40.7% of a dose excreted in 8 hours.
[A182174]
[L7829]
The pharmacokinetics of this drug have not been evaluated in depth in man. In a small group of healthy research volunteers, 90% of a daily 600 mg oral dose of phenazopyridine hydrochloride was found to be excreted within 1 day, with 41% as unchanged drug and 49% as phenazopyridine metabolites.
[L7826]
Another study in humans determined that 80.07 ± 4.54 percent of the dose was cleared in the urine within 48 hours of administration.
[A182156]
In rats, biliary excretion was high, with 40.7% of a dose excreted in 8 hours.
[A182174]
Clearance
This drug is rapidly excreted by the kidneys, up to 65% of a dose administered orally may be excreted as unchanged drug in the urine. The clearance of phenazopyridine may be decreased with impaired renal or hepatic function and is contraindicated in these conditions.
[L7826]
[L7826]
Drug targets(1)
Proteins and enzymes this drug interacts with in the body
Sodium channel protein type 1 subunit alpha
SCN1A
inhibitor
Specific functionvoltage-gated monoatomic ion channel activity involved in regulation of presynaptic membrane potential
Cellular location
Cell membrane
General function & pharmacology
Pore-forming subunit of Nav1.1, a voltage-gated sodium (Nav) channel that directly mediates the depolarizing phase of action potentials in excitable membranes. Navs, also called VGSCs (voltage-gated sodium channels) or VDSCs (voltage-dependent sodium channels), operate by switching between closed and open conformations depending on the voltage difference across the membrane. In the open conformation they allow Na(+) ions to selectively pass through the pore, along their electrochemical gradient.
The influx of Na(+) ions provokes membrane depolarization, initiating the propagation of electrical signals throughout cells and tissues .
PMID:14672992
By regulating the excitability of neurons, ensures that they respond appropriately to synaptic inputs, maintaining the balance between excitation and inhibition in brain neural circuits (By similarity). Nav1.1 plays a role in controlling the excitability and action potential propagation from somatosensory neurons, thereby contributing to the sensory perception of mechanically-induced pain (By similarity)
The influx of Na(+) ions provokes membrane depolarization, initiating the propagation of electrical signals throughout cells and tissues .
PMID:14672992
By regulating the excitability of neurons, ensures that they respond appropriately to synaptic inputs, maintaining the balance between excitation and inhibition in brain neural circuits (By similarity). Nav1.1 plays a role in controlling the excitability and action potential propagation from somatosensory neurons, thereby contributing to the sensory perception of mechanically-induced pain (By similarity)
Scientific references(13)
Shore S.N., Britnell S.R., Brown J.N.
Safety analysis of long-term phenazopyridine use for radiation cystitis. J Oncol Pharm Pract. 2019 Apr 22:1078155219842646.
doi: 10
1177/1078155219842646
Suter D.M., Preynat-Seauve O., Tirefort D., Feki A., Krause K.H.
Phenazopyridine induces and synchronizes neuronal differentiation of embryonic stem cells.
Journal Cell Molecular Medicine
2009 Sep13(9B):3517-27. doi: 10.1111/j.1582-4934.2009.00660.x
Rehfuss A., Mahon J., Sorokin I., Smith C., Stein B.S.
Phenazopyridine: A Preoperative Way to Identify Ureteral Orifices.
Urology
2018 May115:36-38. doi: 10.1016/j.urology.2018.02.023. Epub 2018 Mar 1
Onder A.M., Espinoza V., Berho M.E., Chandar J., Zilleruelo G., Abitbol C.
Acute renal failure due to phenazopyridine (Pyridium) overdose: case report and review of the literature.
Pediatrics Nephrol
2006 Nov21(11):1760-4. doi: 10.1007/s00467-006-0196-1. Epub 2006 Aug 1
Gold N.A., Bithoney W.G.
Methemoglobinemia due to ingestion of at most three pills of pyridium in a 2-year-old: case report and review.
The Journal of Emergency Medicine
200325(2):143-148. doi: 10.1016/s0736-4679(03)00162-8
Murphy T., Fernandez M.
Acquired methemoglobinemia from phenazopyridine use.
International Journal Emerg Medicine
2018 Nov 1211(1):45. doi: 10.1186/s12245-018-0208-5
Chang L.C., Kuo C.W., Chau T., Lin S.H.
Phenazopyridine-induced hemolytic anemia in advanced kidney disease.
Journal American Geriatr Society
2014 Dec62(12):2464-6. doi: 10.1111/jgs.13161
Aizawa N., Wyndaele J.J.
Effects of phenazopyridine on rat bladder primary afferent activity, and comparison with lidocaine and acetaminophen.
Neurourol Urodyn
2010 Nov29(8):1445-50. doi: 10.1002/nau.20886
Thomas B.H., Whitehouse L.W., Solomonraj G., Paul C.J.
Excretion of phenazopyridine and its metabolites in the urine of humans, rats, mice, and guinea pigs.
Journal of Pharmaceutical Sciences
1990 Apr79(4):321-5. doi: 10.1002/jps.2600790410
Johnson W.J., Chartrand A.
The metabolism and excretion of phenazopyridine hydrochloride in animals and man.
Toxicology Applied Pharmacology
1976 Aug37(2):371-6. doi: 10.1016/0041-008x(76)90100-9
Li K.J., Chen Q.H., Zhang Z., Zhou P., Li P., Liu J., Zhu J.
Determination of phenazopyridine in human plasma by GC-MS and its pharmacokinetics.
Journal Chromatogr Science
2008 Sep46(8):686-9. doi: 10.1093/chromsci/46.8.686
Thomas B.H., Whitehouse L.W., Solomonraj G., Paul C.J.
Metabolism and disposition of phenazopyridine in rat.
Xenobiotica
199323(2):99-105. doi: 10.3109/00498259309059365
Pitre D., Maffei-Facino R.
Isolation and Identification of Oxidized Metabolites of Phenazopyridine from Rat Urine. Recent Developments in Mass Spectrometry in Biochemistry and Medicine. 1978;:127-132.
doi: 10
1007/978-1-4613-3991-5_9
ATC classification(1 code)
ATC G04BX06
Affected organisms(1)
Humans and other mammals
International brands(11)
Salt forms(1)
Phenazopyridine hydrochloride(DBSALT000915)
Experimental properties(5)
Commercial products(415)
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Show
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Phenazopyridine
Additional database identifiers
Drugs Product Database (DPD)
20246
ChemSpider
4592
BindingDB
50420356
ZINC
ZINC000095483532
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10585
GenAtlas
SCN1A
GeneCards
SCN1A
GenBank Gene Database
AF225985
GenBank Protein Database
12642270
Guide to Pharmacology
578
UniProt Accession
SCN1A_HUMAN
International reference pricing
17 formulations
Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.
From $0.19/tablet
To $3.59/g
Prodium 95 mg tablet
$0.19/tablet
Woman's wellbeing uti rlf tablet
$0.21/tablet
Azo-gesic 95 mg tablet
$0.22/tablet
CVS Pharmacy urinary pain rlf 95 mg tablet
$0.22/tablet
Azo standard 95 mg tablet
$0.33/tablet
Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.
DrugBank citations
If you use DrugBank data in your research, please cite the following publications:
Knox C., Wilson M., Klinger C.M., et al
DrugBank 6.
0: the DrugBank Knowledgebase for 2024
Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275
Wishart D.S., Feunang Y.D., Guo A.C., et al
DrugBank 5.
0: a major update to the DrugBank database for 2018
Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082
Show earlier publications
Law V., Knox C., Djoumbou Y., et al
DrugBank 4.
0: shedding new light on drug metabolism
Nucleic Acids Res. 2014 Jan 142(1):D1091-7
Knox C., Law V., Jewison T., et al
DrugBank 3.
0: a comprehensive resource for 'omics' research on drugs
Nucleic Acids Res. 2011 Jan39(Database issue):D1035-41
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a knowledgebase for drugs, drug actions and drug targets.
Nucleic Acids Research
2008 Jan36(Database issue):D901-6
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a comprehensive resource for in silico drug discovery and exploration.
Nucleic Acids Research
2006 Jan 134(Database issue):D668-72
Source: go.drugbank.comCC BY-NC 4.0
Updated 27 days ago(8 Mar 2026)