The urinary system filters blood, produces, stores, and eliminates urine. It also maintains fluid/electrolyte balance and regulates blood pressure. Medications targeting this system treat infections, storage/elimination problems, kidney stones, and kidney disease complications. 

1. Medications for Urinary Tract Infections (UTIs)

UTIs are common bacterial infections. Antibiotics are the main treatment.

a. Antibiotics

Antibiotic choice depends on infection type, severity, location, patient factors, and resistance patterns.

• Trimethoprim-Sulfamethoxazole (TMP-SMX): (Bactrim)

  • Mechanism: Inhibits bacterial folic acid synthesis (bactericidal).

  • Uses: First-line for uncomplicated lower UTIs.

  • Side Effects: Nausea, vomiting, diarrhea, rash, photosensitivity. Rare: severe allergic reactions, bone marrow suppression.

  • Nursing Implications: Administer with water. Complete full course. Advise sun protection. Monitor for rash/allergy. Assess sulfa allergy.

• Nitrofurantoin: (Macrobid, Macrodantin)

  • Mechanism: Damages bacterial DNA/molecules in the urinary tract.

  • Uses: Uncomplicated lower UTIs (treatment/prevention). Not for kidney infections.

  • Side Effects: Nausea, vomiting, anorexia (take with food), headache. Harmless brown urine. Rare: pulmonary toxicity (long-term), hepatotoxicity, neuropathy.

  • Nursing Implications: Administer with food. Educate on urine color. Report respiratory/nerve symptoms.

• Fluoroquinolones: (Ciprofloxacin, Levofloxacin)

  • Mechanism: Inhibit bacterial DNA enzymes (bactericidal).

  • Uses: Complicated UTIs, pyelonephritis, resistant UTIs.

  • Side Effects: Nausea, diarrhea, headache, dizziness. Serious: tendinitis/rupture, neuropathy, CNS effects, QT prolongation.

  • Nursing Implications: Separate from antacids, iron, zinc, dairy. Report tendon pain/swelling, nerve symptoms. Advise photosensitivity precautions.

• Beta-Lactam Antibiotics: (Amoxicillin, Cephalexin)

  • Mechanism: Inhibit bacterial cell wall synthesis.

  • Uses: Uncomplicated UTIs, sometimes in pregnancy.

  • Side Effects: Rash, diarrhea, nausea, allergy.

  • Nursing Implications: Assess penicillin/cephalosporin allergies. Complete full course.

b. Urinary Analgesics

Relieve UTI symptoms; do not treat infection.

• Phenazopyridine: (Pyridium)

  • Mechanism: Local anesthetic effect on urinary tract mucosa.

  • Uses: Relieves pain, burning, urgency, frequency with UTIs.

  • Side Effects: Orange/red urine (harmless, stains). Headache, dizziness, GI upset.

  • Nursing Implications: Educate on urine color change. Explain it’s for symptoms only (short-term use with antibiotic).

2. Medications for Overactive Bladder (OAB)

Treat urgency, frequency, incontinence by relaxing the bladder.

• Anticholinergics/Antimuscarinics: (Oxybutynin, Tolterodine, Solifenacin)

  • Mechanism: Block acetylcholine on bladder muscle, causing relaxation, increasing capacity.

  • Uses: Reduce OAB symptoms.

  • Side Effects: Dry mouth, constipation, blurred vision, dry eyes, urinary retention, dizziness, confusion (older adults).

  • Nursing Implications: Educate on side effects/management (sugar-free candy, fiber). Monitor for retention. Use cautiously in older adults. Contraindicated in narrow-angle glaucoma, obstructive retention.

• Beta-3 Adrenergic Agonists: (Mirabegron)

  • Mechanism: Stimulate beta-3 receptors in bladder, causing relaxation during filling.

  • Uses: Treat OAB. Alternative to anticholinergics.

  • Side Effects: Hypertension, headache, nasopharyngitis, UTIs.

  • Nursing Implications: Monitor blood pressure (caution with uncontrolled HTN).

3. Medications for Urinary Retention

Treat inability to empty bladder (obstruction or nerve issues).

• Alpha-Blockers: (Tamsulosin, Terazosin)

  • Mechanism: Relax smooth muscle in prostate/bladder neck, improving flow.

  • Uses: BPH symptoms in men (retention, weak stream).

  • Side Effects: Orthostatic hypotension, dizziness, headache, ejaculatory dysfunction.

  • Nursing Implications: Monitor BP (position changes). Educate on dizziness risk (change positions slowly, take at bedtime).

• 5-alpha Reductase Inhibitors: (Finasteride, Dutasteride)

  • Mechanism: Shrink prostate by blocking DHT conversion.

  • Uses: Treat BPH (takes months).

  • Side Effects: Sexual side effects (libido, ED), gynecomastia. Affects PSA levels.

  • Nursing Implications: Educate on delayed effect. Pregnant women avoid handling broken tablets.

• Cholinergics: (Bethanechol)

  • Mechanism: Stimulate muscarinic receptors, increasing bladder muscle contraction.

  • Uses: Non-obstructive urinary retention (post-op, neuro). Not for obstruction.

  • Side Effects: Cholinergic effects (SLUDGE: salivation, lacrimation, urination, defecation), cramps, nausea, vomiting, diarrhea, flushing, sweating, bradycardia, hypotension.

  • Nursing Implications: Administer on empty stomach. Monitor for cholinergic side effects.

4. Medications for Kidney Stones

Prevent certain stones or aid passage.

• Alpha-Blockers: (Tamsulosin) Relax ureter muscle to aid stone passage.

• Thiazide Diuretics: (Hydrochlorothiazide) Prevent calcium stones by reducing calcium excretion.

• Potassium Citrate: Alkalinizes urine to prevent uric acid and calcium oxalate stones.

• Allopurinol: Reduces uric acid production to prevent uric acid stones.

5. Diuretics

Act on kidneys to increase urine output (Thiazides, Loops, Potassium-Sparing). Used for fluid overload, hypertension. Mechanisms/nursing implications related to fluid/electrolytes are key.

6. Medications Affecting Kidney Function

Protect function, slow disease, manage complications (covered in Renal Failure lesson).

• ACE Inhibitors/ARBs: Protect kidneys in diabetes/hypertension.

• Phosphate Binders: Manage hyperphosphatemia in CKD.

• Vitamin D Analogs: Manage hypocalcemia/renal osteodystrophy in CKD.

• Erythropoiesis-Stimulating Agents (ESAs): Treat anemia in CKD.

Nursing Considerations Across Urinary System Medications

Caring for patients on these meds requires assessment, monitoring, and education.

• Assessment: Urinary symptoms, voiding pattern, urine characteristics, fluid I&O, signs of infection/stones, patient knowledge.

• Monitoring: Accurate I&O, urine characteristics, symptom relief, side effects, lab tests (kidney function, electrolytes, cultures), blood pressure.

• Administration: Correct administration (timing, with/without food, specific instructions). Educate on expected urine color changes (Phenazopyridine).

• Patient Education: Medication purpose, dose, schedule, duration, side effects (when to report), adherence importance, lifestyle/diet (fluid intake, bladder irritants, hygiene, stone prevention).

• Fluid Management: Educate on appropriate fluid intake based on condition (increased for UTIs/stones, controlled for fluid overload/CKD).

• Bowel Function: Monitor/manage constipation, which can worsen urinary symptoms.

• Privacy and Dignity: Provide support for patients with urinary issues.