Action and Spectrum

Actions and Spectrum: 

phenazopyridine is a medication used to relieve the symptoms of urinary tract infections (UTIs), such as pain, burning, and urgency. It is not an antibiotic and does not treat the underlying infection. 

The exact mechanism of action of phenazopyridine has yet to be well understood, but it is thought to work by directly acting on the lining of the urinary tract. It is believed to have both analgesic and local anesthetic properties. It can relieve .0the symptoms of UTIs by reducing inflammation and irritation in the urinary tract. 

phenazopyridine has a local effect on the urinary tract and does not have systemic effects. It is ineffective against systemic infections or other infections outside the urinary tract. It is used as an adjunct therapy to antibiotics to relieve UTI symptoms. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Vertigo 

Pruritus 

Methemoglobinemia 

Hemolytic anemia 

Transient ARF 

Staining of contact lenses 

Headache 

Rash 

Mild GI disturbances 

Skin pigmentation 

Renal calculi 

Hepatic/renal toxicity 

Black Box Warning

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

• Hypersensitivity: phenazopyridine should not be used in patients with known hypersensitivity or allergy to the medication. 

• Renal impairment: The medication should not be used in patients with severe renal impairment, as it can accumulate in the body and cause toxicity. 

• Hepatic impairment: phenazopyridine should be used cautiously in patients with hepatic impairment, as it can be metabolized in the liver and cause toxicity. 

• Glucose-6-phosphate dehydrogenase (G6PD) deficiency: Patients with G6PD deficiency should avoid phenazopyridine, as it can cause hemolysis (destruction of red blood cells). 

• Pregnancy and breastfeeding: The medication should be used cautiously in pregnant or breastfeeding women, as there is limited information about its safety in these populations. 

• Children under the age of 6: phenazopyridine is not recommended for use in children under 6. 

Caution: 

Use in elderly patients: Elderly patients may be more susceptible to the side effects of phenazopyridine, such as dizziness or confusion. 

Use in patients with renal impairment: phenazopyridine should be used cautiously in patients with renal impairment, as it can accumulate in the body and cause toxicity.

Use with other medications: phenazopyridine may interact with other medications, such as antibiotics or antifungal agents, which may affect its efficacy or increase the risk of side effects. 

Use in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency: Patients with G6PD deficiency should use phenazopyridine cautiously, as it can cause hemolysis (destruction of red blood cells). 

Use in patients with liver disease: phenazopyridine should be used cautiously in patients with liver disease, as it can be metabolized in the liver and cause toxicity. 

Use during pregnancy or breastfeeding: The safety of phenazopyridine during pregnancy or breastfeeding has not been established, and it should only be used if the potential benefits outweigh the potential risks. 

Pregnancy / Lactation

Pregnancy consideration: Insufficient data available 

Lactation: Excretion of the drug in human breast milk is unknown 

Pregnancy category: 

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester.   

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

phenazopyridine is a medication primarily used to relieve the symptoms associated with urinary tract infections, such as pain, burning, and urgency. The exact mechanism of action of phenazopyridine is not entirely understood, but it is believed to work by providing a local analgesic effect on the urinary tract mucosa. 

Pharmacodynamics: 

phenazopyridine is a medication that works locally in the urinary tract to relieve pain and other symptoms associated with infections. The exact mechanism of action of phenazopyridine is not fully understood. Still, it is believed to work by exerting a local anesthetic effect on the mucous membranes lining the urinary tract.  

phenazopyridine works by blocking the conduction of sensory impulses, which reduces the sensation of pain and discomfort in the urinary tract. It also has an anti-inflammatory effect, which can help to reduce inflammation and swelling in the urinary tract. phenazopyridine has a rapid onset of action, with pain relief usually occurring within 30 minutes to 1 hour after taking the medication. 

Pharmacokinetics: 

Absorption 

phenazopyridine is rapidly absorbed in the gastrointestinal tract, with peak plasma concentrations reached within 1-2 hours after oral administration. Absorption is enhanced when the medication is taken with food.  

Distribution 

phenazopyridine is rapidly distributed throughout the body, with the highest concentrations in the kidneys, liver, and bladder. The drug does not appear to bind to plasma proteins.  

Metabolism 

phenazopyridine is primarily metabolized in the liver by the enzyme glucuronyl transferase. The primary metabolite is conjugated phenazopyridine, which is excreted in the urine. Only a tiny amount of the drug is metabolized to other inactive metabolites. 

Elimination and Excretion 

phenazopyridine and its metabolites are primarily excreted in the urine, with up to 65-75% of the dose excreted unchanged within 24 hours. The elimination half-life is approximately 6 hours. 

Adminstartion

Administration: 

phenazopyridine is available in several forms, including tablets, capsules, and liquid suspensions. Here are some general guidelines for the administration of phenazopyridine: 

• phenazopyridine is usually taken orally, after meals, with a full glass of water. 
• The phenazopyridine dosage may vary depending on the patient’s age, weight, and condition. It is essential to follow the dosage instructions provided by your healthcare provider or the medication label. 
• phenazopyridine should be taken for the duration recommended by your healthcare provider. Taking phenazopyridine for longer than two days without medical supervision is not recommended. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: phenazopyridine 

Why do we use phenazopyridine? 

• phenazopyridine is a medication primarily used to relieve the symptoms associated with urinary tract infections (UTIs), such as pain, burning, and urgency. It works by providing a local analgesic effect on the urinary tract mucosa. 
• phenazopyridine is not an antibiotic and does not treat the underlying infection causing the UTI. It is combined with antibiotics to provide symptomatic relief while the infection is treated. 
• In addition to its use for UTI symptoms, phenazopyridine may relieve discomfort associated with other urinary tract conditions, such as urethritis, cystitis, and prostatitis. 
• phenazopyridine may also be used in some diagnostic procedures, such as cystoscopy or catheterization, to relieve discomfort during the procedure.