Generic Name

Sulfapyridine

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Classification

FDA Approved Indications

• Treatment of bacterial infections caused by susceptible organisms

Mechanism of Action

Inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA), leading to inhibition of bacterial growth.

Dosage and Administration

Adult: 250-500 mg orally every 6-8 hours, dose adjusted based on severity and organism susceptibility

Pediatric: Not typically used in pediatric patients due to availability of newer agents

Geriatric: Adjust dose based on renal function; careful monitoring for adverse effects

Renal Impairment: Dose adjustment needed; usually reduced or extended dosing interval

Hepatic Impairment: Use with caution; no specific adjustment detailed

Pharmacokinetics

Absorption: Well absorbed from the gastrointestinal tract

Distribution: Widely distributed including into cerebrospinal fluid and urine

Metabolism: Partially metabolized in the liver

Excretion: Primarily via kidneys in unchanged form

Half Life: Approximately 10-20 hours

Contraindications

• Hypersensitivity to sulfamethoxazole or other sulfonamides
• History of hypersensitivity reactions to sulfonamides

Precautions

• Use with caution in patients with compromised renal or hepatic function, porphyria, or blood dyscrasias; risk of hypersensitivity reactions

Adverse Reactions - Common

• Rash or skin hypersensitivity reactions (Less common)
• Gastrointestinal upset (Common)

Adverse Reactions - Serious

• Stevens-Johnson syndrome (Rare)
• Blood dyscrasias such as agranulocytosis or aplastic anemia (Rare)
• Drug fever, hepatotoxicity (Rare)

Drug-Drug Interactions

• Methotrexate (increased toxicity)
• Warfarin (increased bleeding risk)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Patient/Family Teaching

• Take medication as prescribed and complete the course
• Report any skin rash, fever, or unusual bleeding immediately
• Maintain adequate hydration
• Avoid exposure to sunlight or tanning beds due to photosensitivity

Special Considerations

Black Box Warnings:

• Hypersensitivity reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, can be severe and life-threatening

Genetic Factors: None specifically noted for sulfapyridine

Lab Test Interference: May cause false positive results in certain laboratory tests such as urinary ketones

Overdose Management

Signs/Symptoms: Nausea, vomiting, dizziness, headache, bloody dyscrasias, allergic reactions

Treatment: Supportive care; rapid removal of the drug through gastric lavage or activated charcoal if recent ingestion; hemodialysis in severe cases may be considered

Storage and Handling

Storage: Store at room temperature, away from moisture and light

Stability: Stable under recommended storage conditions for the period specified by the manufacturer