Pyridium (Phenazopyridine) Dosage and Administration
The recommended adult dosage of Pyridium (phenazopyridine) is 200 mg three times daily after meals, or alternatively, 100 mg tablets can be given as two tablets three times daily after meals. 1
Standard Dosing Guidelines
- For adults, the standard dose is 200 mg three times daily after meals 1
- Alternatively, if using 100 mg tablets, administer two tablets three times daily after meals 1
- When used alongside antibiotics for urinary tract infections, phenazopyridine administration should not exceed 2 days 1
Special Population Considerations
- For children, dosing should be approached with extreme caution as even small doses can cause toxicity 2
- A case report documented methemoglobinemia in a 2-year-old child who ingested just three 200 mg tablets (approximately 50 mg/kg) 2
- Elderly patients may be at higher risk for adverse effects, including rare complications such as myelosuppressive pancytopenia 3
Administration Timing
- Taking phenazopyridine after meals may help reduce gastrointestinal side effects 1
- For procedures such as cystoscopy, administering 200 mg approximately 20 minutes before the procedure and then 200 mg every 8 hours (total of three doses) can help reduce pain during and after the procedure 4
Duration of Treatment
- Limit treatment duration to 2 days when used concurrently with antibiotics for urinary tract infections 1
- Prolonged use without medical supervision should be avoided due to potential toxicity 5
Monitoring and Precautions
- Monitor for yellow/orange discoloration of skin or sclera, which indicates accumulation of the medication 5
- Be alert for signs of methemoglobinemia (cyanosis, headache, fatigue, dizziness, shortness of breath) especially in children or after overdose 2
- Watch for symptoms of acute renal failure, which can occur even with relatively small overdoses (as little as 1,200 mg in one case report) 5
- The medication can interfere with urinalysis results due to its orange-red color 1
Overdose Management
- In cases of overdose, treatment may include N-acetylcysteine, intravenous carnitine, and alkalinization of urine 5
- For methemoglobinemia, methylene blue may be required as treatment 2
Remember that phenazopyridine is intended only for symptomatic relief and does not treat the underlying cause of urinary symptoms. It should always be used as directed and for the shortest duration necessary to control symptoms.