Pharmacology of the Urinary, Reproductive, and Labor Systems

Clinical Tip: Incontinence Classification To select the correct therapy, distinguish between:

• Stress vs. Urge: Physical pressure vs. bladder contraction signals.
• Overflow: Bladder is too full to hold more.
• Nocturnal: Occurring during sleep.
• Functional: Physical or cognitive inability to reach the toilet in time.
• Reflex: Involuntary voiding due to spinal cord issues.

Male Reproductive Health

Male GU issues often involve Benign Prostatic Hyperplasia (BPH), which presents through both mechanical obstruction (physical size of the prostate) and dynamic obstruction (smooth muscle tone).

BPH Management

1. 5-Alpha Reductase Inhibitors (e.g., Finasteride, Dutasteride): These drugs inhibit the conversion of testosterone to dihydrotestosterone (DHT), effectively shrinking the prostate.
   • PSA Monitoring: These drugs affect Prostate-Specific Antigen (PSA) levels, which can complicate cancer screening.
   • Safety: They are teratogenic (can cause birth defects). Patients must be cautioned against donating blood while taking these medications.
2. Alpha-1 Antagonists (e.g., Terazosin, Silodosin): These relax the smooth muscle of the prostate and bladder neck.
   • Selectivity: Clinicians must distinguish between non-selective agents used for hypertension (HTN) and selective agents used specifically for BPH.
   • Silodosin: Requires careful monitoring for drug interactions.

Erectile Dysfunction (ED)

PDE-5 Inhibitors (e.g., Sildenafil) are used to treat ED by facilitating the erectile process.

• Administration: The effect of food on absorption must be discussed with patients.
• Risks: The most serious side effect to monitor is priapism (a prolonged, painful erection).
• Interactions: Clinicians must identify drugs that may cause ED or interact dangerously with PDE-5 inhibitors.

Hormonal and Reproductive Health

Menstrual Disorders and Diagnosis

Clinicians must use precise terminology to describe menstrual irregularities:

• Amenorrhea: Absence of menses (Primary: never started; Secondary: stopped after previously regular cycles).
• Menorrhagia: Heavy or prolonged bleeding.
• Metrorrhagia: Bleeding between periods.
• Polymenorrhea: Frequent cycles.
• Oligomenorrhea: Infrequent cycles.
• Dysmenorrhea: Painful menstruation.

Hormonal Management and Contraception

Treatment involves balancing estrogen and progestin levels.

• Hormonal Therapy: Management depends on whether there is an excess or deficiency of these hormones.
• Combined Oral Contraceptives (COC): Patient education is vital, especially regarding missed pills during the first week of a 28-day pack.
• Androgens (Testosterone): Administered via transdermal patches or gels. Education must focus on priority side effects and contraindications.

Labor and Delivery (L&D)

Pharmacology in L&D focuses on the timing and intensity of uterine contractions.

• Labor Induction: Clinicians must determine which patients qualify for induction based on specific medical criteria.
• Preterm Labor Management:
  • Tocolytics: Medications used to stop or slow down labor to prevent premature birth.
  • Oxytocics: Medications used to promote or induce labor.
• Dinoprostone: A medication used in the labor process that requires specific administration protocols.

Exam Summary Table: L&D Pharmacology