Phenazopyridine


Description

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 previousl...

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Pharmacology

Indication

Phenazopyridine hydrochloride is indicated to relieve uncomfortable symptoms that occur as a consequ... Read more

Pharmacodynamic

Phenazopyridine acts as a local anesthetic offering relief from irritating conditions of the urinary... Read more

Mechanism of action

The full mechanism of action of phenazopyridine is not fully elucidated[ Read more

Absorption

Phenazopyridine is absorbed in the gastrointestinal tract.[ Read more

Protein binding

Information currently not available.

Volume of distribution

Small, trace quantities of phenazopyridine are thought to cross the placenta and the blood-brain bar... Read more

Clearance

This drug is rapidly excreted by the kidneys, up to 65% of a dose administered orally may be excrete... Read more

Half life

The mean elimination half-life of phenazopyridine is 7.35 hours in rats with healthy renal function.... Read more

Route of elimination

Up to 65% of an oral phenazopyridine dose is quickly excreted by the kidneys as unchanged drug measu... Read more

Toxicity

The oral LD50 of phenazopyridine in rats is 472 mg/kg.[ Read more


Adverse Effects

Effect Regions Age Groups Incidences Evidence Type
Hepatotoxicity Canada
Reversible loss of colour vision Canada
Ear pain Canada
Eye irritation Canada
Pancytopenia Canada
Leukopenia Canada
Neutropenia Canada
Headache US
Varying Reports
Rash US
Varying Reports
Diarrhea US
Varying Reports
Vomiting US
Varying Reports
Nausea US
Varying Reports
Hypersensitivity hepatitis US
Varying Reports
Anaphylactoid-like reaction US
Varying Reports
Discoloration US
Varying Reports
Pruritus US
Varying Reports
Visual disturbances US
Varying Reports
Sulfhemoglobinemia US
Varying Reports
Hemolytic Anemia US
Varying Reports
Methemoglobinemia US
Varying Reports
Aseptic Meningitis US
Varying Reports
Discoloration of Body Fluids US
Varying Reports
Jaundice US
Varying Reports
Renal Calculi US
Varying Reports
Hepatic toxicity US
Varying Reports
Renal Toxicity US
Varying Reports
Hemolysis US
Varying Reports

Contraindications

  • Regions: US
  • Patient Conditions:
      • Name: G6PD Deficiency
      • Drugbank Id: DBCOND0077795
  • Regions: Canada
  • Patient Conditions:
      • Name: Liver Diseases
      • Drugbank Id: DBCOND0027940
  • Regions: US
  • Patient Conditions:
      • Name: Renal Insufficiency
      • Drugbank Id: DBCOND0031387

Food Interactions

  • Take with food to reduce irritation.

Interactions

Type in a drug name to check for interaction with Phenazopyridine

Phenazopyridine may decrease the excretion rate of Abacavir which could result in a higher serum level.
Phenazopyridine may decrease the excretion rate of Acarbose which could result in a higher serum level.
The risk or severity of nephrotoxicity can be increased when Phenazopyridine is combined with Aceclofenac.
The risk or severity of nephrotoxicity can be increased when Phenazopyridine is combined with Acemetacin.
The risk or severity of methemoglobinemia can be increased when Acetaminophen is combined with Phenazopyridine.
Acetazolamide may increase the excretion rate of Phenazopyridine which could result in a lower serum level and potentially a reduction in efficacy.
The risk or severity of nephrotoxicity can be increased when Acetylsalicylic acid is combined with Phenazopyridine.
Phenazopyridine may decrease the excretion rate of Aclidinium which could result in a higher serum level.
Phenazopyridine may decrease the excretion rate of Acrivastine which could result in a higher serum level.
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 Phenazopyridine is combined with Adefovir.
The risk or severity of nephrotoxicity can be increased when Adefovir dipivoxil is combined with Phenazopyridine.
Phenazopyridine may decrease the excretion rate of Albutrepenonacog alfa which could result in a higher serum level.
The risk or severity of nephrotoxicity can be increased when Phenazopyridine is combined with Alclofenac.
Phenazopyridine may decrease the excretion rate of Aldesleukin which could result in a higher serum level.
The risk or severity of nephrotoxicity and hypocalcemia can be increased when Phenazopyridine is combined with Alendronic acid.
Phenazopyridine may decrease the excretion rate of Allopurinol which could result in a higher serum level.
Phenazopyridine may decrease the excretion rate of Allylestrenol which could result in a higher serum level.
Phenazopyridine may decrease the excretion rate of Almasilate which could result in a higher serum level.
The risk or severity of nephrotoxicity can be increased when Phenazopyridine is combined with Alminoprofen.

References

  • 1 . Shore SN, Britnell SR, Brown JN: Safety analysis of long-term phenazopyridine use for radiation cystitis. J Oncol Pharm Pract. 2019 Apr 22:1078155219842646. doi: 10.1177/1078155219842646. [PubMed: 31006341]
  • 2 . Suter DM, Preynat-Seauve O, Tirefort D, Feki A, Krause KH: Phenazopyridine induces and synchronizes neuronal differentiation of embryonic stem cells. J Cell Mol Med. 2009 Sep;13(9B):3517-27. doi: 10.1111/j.1582-4934.2009.00660.x. [PubMed: 20196783]
  • 3 . Rehfuss A, Mahon J, Sorokin I, Smith C, Stein BS: Phenazopyridine: A Preoperative Way to Identify Ureteral Orifices. Urology. 2018 May;115:36-38. doi: 10.1016/j.urology.2018.02.023. Epub 2018 Mar 1. [PubMed: 29501712]
  • 4 . Onder AM, Espinoza V, Berho ME, Chandar J, Zilleruelo G, Abitbol C: Acute renal failure due to phenazopyridine (Pyridium) overdose: case report and review of the literature. Pediatr Nephrol. 2006 Nov;21(11):1760-4. doi: 10.1007/s00467-006-0196-1. Epub 2006 Aug 1. [PubMed: 16897003]
  • 5 . Gold NA, Bithoney WG: Methemoglobinemia due to ingestion of at most three pills of pyridium in a 2-year-old: case report and review. J Emerg Med. 2003 Aug;25(2):143-8. [PubMed: 12901999]
  • 6 . Murphy T, Fernandez M: Acquired methemoglobinemia from phenazopyridine use. Int J Emerg Med. 2018 Nov 12;11(1):45. doi: 10.1186/s12245-018-0208-5. [PubMed: 31179913]
  • 7 . Chang LC, Kuo CW, Chau T, Lin SH: Phenazopyridine-induced hemolytic anemia in advanced kidney disease. J Am Geriatr Soc. 2014 Dec;62(12):2464-6. doi: 10.1111/jgs.13161. [PubMed: 25516057]
  • 8 . Aizawa N, Wyndaele JJ: Effects of phenazopyridine on rat bladder primary afferent activity, and comparison with lidocaine and acetaminophen. Neurourol Urodyn. 2010 Nov;29(8):1445-50. doi: 10.1002/nau.20886. [PubMed: 20976818]
  • 9 . Thomas BH, Whitehouse LW, Solomonraj G, Paul CJ: Excretion of phenazopyridine and its metabolites in the urine of humans, rats, mice, and guinea pigs. J Pharm Sci. 1990 Apr;79(4):321-5. doi: 10.1002/jps.2600790410. [PubMed: 2352143]
  • 10 . Johnson WJ, Chartrand A: The metabolism and excretion of phenazopyridine hydrochloride in animals and man. Toxicol Appl Pharmacol. 1976 Aug;37(2):371-6. doi: 10.1016/0041-008x(76)90100-9. [PubMed: 982458]
  • 11 . Li KJ, Chen QH, Zhang Z, Zhou P, Li P, Liu J, Zhu J: Determination of phenazopyridine in human plasma by GC-MS and its pharmacokinetics. J Chromatogr Sci. 2008 Sep;46(8):686-9. doi: 10.1093/chromsci/46.8.686. [PubMed: 18796223]
  • 12 . Thomas BH, Whitehouse LW, Solomonraj G, Paul CJ: Metabolism and disposition of phenazopyridine in rat. Xenobiotica. 1993 Feb;23(2):99-105. [PubMed: 8498084]
  • 13 . Pitre D, Maffei-Facino R: Isolation and identification of two hydroxylated metabolites of phenazopyridine in rat urine. Farmaco Sci. 1977 Jun;32(6):453-60. [PubMed: 872925]
  • 14 . Phenazopyridine Hydrochloride [Link]
  • 15 . Drug summary: phenazopyridine [Link]
  • 16 . FDA information Phenazopyridine [Link]
  • 17 . HMDB, phenazopyridine [Link]
  • 18 . Phenazopyridine DailyMed [Link]
  • 19 . MSDS, Phenazopyridine [Link]
  • 20 . UPMC: Final Diagnosis -- Suicide Attempt with Ingestion of Pyridium Tablets [Link]
  • 21 . Intracellular Drug Bioavailability: Effect of Neutral Lipids and Phospholipids [Link]
  • 22 . O Factors Affecting Drug Metabolism [Link]
  • 23 . Phenazopyridine hydrochloride [Link]

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