Pharmacology Notes - Reproductive and GU System Medications

Notes on Drugs to Treat Conditions of the Reproductive/GU System

Medications for Conditions of the Male Reproductive System

  • Testosterone

    • Treats hypogonadism, delayed puberty, and testicular failure in men

    • Can treat certain breast cancers in women (antagonizes estrogen)

    • Administration forms: transdermal patch, gel, underarm liquid, implantable pellets, buccal tablets

    • Adverse effects: virilization, growth of undiagnosed prostate cancers, closure of epiphyseal plates, gynecomastia

  • Medications for Benign Prostatic Hyperplasia (BPH)

    • Finasteride (5 Alpha Reductase Inhibitor)

    • Decreases testosterone production in the prostate, slowly shrinking tissue (6-12 months for effect)

    • Does not affect serum testosterone levels

    • Adverse effects: decreased libido, reduced ejaculate volume, gynecomastia, reduced PSA levels

    • Oral administration, generally lifelong

    • Teratogenic effects if crushed pills are handled by women

    • Tamsulosin (Alpha Adrenergic Receptor Antagonist)

    • Relaxes smooth muscle in the prostate and bladder outlet, alleviating BPH symptoms

    • Adverse effects: reduced ejaculate volume, ejaculation failure, retrograde ejaculation

    • Oral administration, once daily at the same time

    • Contraindicated with ED drugs like sildenafil to avoid adverse interactions

  • Drugs for Erectile Dysfunction

    • Sildenafil (PD-5 Inhibitor)

    • Also used for pulmonary hypertension

    • Treats ED of unknown origin or related to diabetes, depression, or hypertension/treatments

    • Increases blood flow to allow erections

    • Adverse effects: priapism, headaches, fainting, dizziness, rare sudden vision/hearing loss

    • Oral administration, as needed, no more than once daily, taken 1 hour before intercourse

    • Important: Do not use within 24 hours of nitroglycerin (for chest pain)

    • Trade name: Viagra

Medications for Alterations in the Urinary System

  • Drugs for Overactive Bladder

    • Beta 3 Adrenergic Agonists

    • Example: Mirabegron, inhibits the signal to contract the bladder

    • Adverse effects: angioedema, hypertension, urinary tract infection, headache, nasopharyngitis

    • Administration: daily tablets or granules dissolved in liquid

    • Watch for interactions with digoxin and warfarin

    • Anticholinergics

    • Example: Oxybutynin, blocks receptors in bladder muscle to promote relaxation

    • Adverse effects: urinary retention, dry mouth, constipation, UTI risk

    • Oral administration 2-4 times per day or transdermal patch

    • Patient considerations: risk of skin breakdown and infections due to drying effects

  • Drugs for Urinary Retention

    • Cholinergics

    • Example: Bethanechol, a cholinergic agonist that promotes bladder contraction

    • Adverse effects: hypotension, bradycardia, excessive gastric acid, diarrhea, bronchoconstriction

    • Administration: 3-4 times per day to encourage bladder emptying

Medications for Menopause

  • Hormone Replacement Therapy (HRT)

    • Estrogen Alone

    • Example: Conjugated Equine Estrogen

    • Relieves menopause symptoms, can lead to endometrial hyperplasia

    • Adverse effects: nausea, hypertension, thromboembolic disorders

    • Contraindicated in patients with estrogen-dependent cancers

    • Estrogen Plus Progesterone

    • Example: Conjugated estrogen with medroxyprogesterone acetate

    • Benefits: relieves menopause symptoms, can prevent osteoporosis

    • Addition of progesterone reduces endometrial cancer risk

Medications for Endometrial Hyperplasia and Endometriosis

  • GnRH Agonist:

    • Example: Leuprolide

    • Mimics menopause, reducing endometriosis symptoms

    • Can also treat prostate cancer

    • Adverse effects: hot flashes, vaginal dryness, risk of osteoporosis

    • IM administration, limited to short-term use (6 months)

  • GnRH Antagonist:

    • Example: Relugolix, estradiol, and norethindrone

    • Works to reduce LH and FSH, controlling uterine bleeding

    • Adverse effects: thromboembolism, liver disease, irregular bleeding

    • Oral administration, daily

  • Progesterone:

    • Prevents endometrial hyperplasia in patients receiving estrogen

    • Treats endometrial overgrowth and dysfunctional uterine bleeding

    • Can be administered orally or IM for symptom relief.