1. Genitourinary drugs
• The GU system consists of the:
– reproductive system (the sex organs) and
– urinary system
• Kidneys
• Ureters
• bladder, and
• urethra.
2. Types of drugs used to treat GU
disorders include:
• diuretics
• urinary tract antispasmodics
• erectile dysfunction therapy drugs
• hormonal contraceptives.
3. Diuretics
• Diuretics trigger the excretion of water and
electrolytes from the kidneys, making these
drugs a primary choice in the treatment of
–renal disease
–Edema
–hypertension, and
–heart failure.
4. Thiazide and thiazide-like diuretics
• used to treat edema caused by
–Kidney disease
–liver disease
–mild or moderate heart failure, and
–Corticosteroid therapy
–estrogen therapy
5. .
• Because these drugs decrease the level of
calcium in urine, they may be used alone or
with other drugs to prevent the development
and recurrence of renal calculi
6. .
• In patients with diabetes insipidus
–a disorder characterized by excessive urine
production and excessive thirst resulting
from reduced secretion of antidiuretic
hormone)
• thiazides paradoxically decrease urine
volume
7. Loop diuretics
• Loop (high ceiling) diuretics are highly potent
drugs.
• They include
• Bumetanide
• ethacrynic acid, and
• furosemide.
8. .
• Loop diuretics, with the exception of
ethacrynic acid, contain sulfa
• A patient who has an allergy to sulfa may
experience an allergic reaction to loop
diuretics
**Use with caution, and alert the patient to this
possibility.
9. .
• used to treat edema associated with
–renal disease
–hepatic cirrhosis
–heart failure
• as well as to treat hypertension
–(usually with a potassium-sparing diuretic
or potassium supplement to prevent
hypokalemia).
10. .
• Ethacrynic acid may also be used for the
short-term management of ascites due to
–Malignancy
–idiopathic edema
–Lymphedema
• Furosemide may be used with mannitol to
treat cerebral edema.
11. Potassium-sparing diuretics
• Potassium-sparing diuretics have weaker
diuretic and antihypertensive effects than
other diuretics
• but provide the advantage of conserving
potassium
–Amiloride
–Spironolactone, and
–Triamterene.
12. Potassium-sparing diuretics are used
to treat:
• edema
• diuretic-induced hypokalemia in patients with
heart failure
• cirrhosis
• nephrotic syndrome
• heart failure
• hypertension.
13. .
• Spironolactone also is used to treat:
–hyperaldosteronism
(excessive secretion of aldosterone)
–hirsutism (excessive hair growth)
–hirsutism associated (polycystic ovary) syndrome
14. .
• Potassium-sparing diuretics are commonly
used with other diuretics to potentiate their
action or counteract their potassium-wasting
effects.
15. Osmotic diuretics
• Osmotic diuretics cause diuresis through
osmosis - moving fluid into the extracellular
spaces
• They include:
–Mannitol
–urea.
16. .
• Osmotic diuretics are used to treat
–acute renal failure
–cerebral edema
• to reduce intracranial and intraocular pressure
• Mannitol is used to
–promote diuresis in acute renal failure and
–promote urinary excretion of toxic
substances.
17. .
• Taking osmotic diuretics with lithium may
increase renal excretion of lithium, which in
turn decreases the effectiveness of lithium.
• Patients having both drugs require lithium
level monitoring.
18. Carbonic anhydrase inhibitors
• Carbonic anhydrase inhibitors are diuretics
that block the action of carbonic anhydrase.
–Acetazolamide
–methazolamide
19.
20. .
• In the kidneys, carbonic anhydrase inhibitors
decrease the availability of hydrogen ions,
which blocks the sodium-hydrogen exchange
mechanisms
• As a result, urinary excretion of sodium,
potassium, bicarbonate, and water increases
• In the eyes, carbonic anhydrase inhibition
reduces aqueous humor production, which
reduces intraocular pressure.
21. .
• Carbonic anhydrase inhibitors are used for
diuresis and to treat glaucoma
• Acetazolamide may also be used to treat
epilepsy and acute mountain sickness.
23. .
• Urinary tract antispasmodics relieve smooth
muscle spasms by inhibiting parasympathetic
activity
• This causes the detrusor and urinary muscles
to relax
24. MoA of Oxybutynin
• When acetylcholine is released within the
bladder, it attaches to receptors on the surface
of smooth muscle in the bladder
• This stimulates bladder contractions.
• Oxybutynin suppresses these involuntary
contractions by blocking the release of
acetylcholine.
• This anticholinergic effect is what makes
oxybutynin useful in the treatment of
overactive bladder
25. .
• Urinary tract antispasmodics are used for
patients with overactive bladders who have
symptoms of:
–urinary frequency
–urgency, or
–incontinence
26. Erectile dysfunction therapy drugs
• Treat penile erectile dysfunction that results
from a lack of blood flowing through the
corpus cavernosum
• This type of erectile dysfunction usually stems
from vascular and neurologic conditions
• Drugs used for erectile dysfunction include
–Alprostadil
–Sildenafil
–tadalafil, and
–vardenafil.
27. .
• Erectile dysfunction drugs are well absorbed
in the GI tract
• sildenafil, tadalafil, and vardenafil are given
orally, metabolized in the liver, and excreted in
feces
• Alprostadil is the exception:
–it’s administered directly into the corpus
cavernosum
–metabolized in the lungs, and
–excreted in urine.
28. .
• Sildenafil, tadalafil, and vardenafil selectively
inhibit the phosphodiesterase receptors
• This causes an increase in blood levels of nitric
oxide, which increases nitric oxide levels
• Nitric oxide relaxes smooth muscles and
allows blood to flow into the corpus
cavernosum, causing an erection.
• Alprostadil acts locally, promoting smooth
muscle relaxation, which causes an increase in
blood flow to the corpus cavernosum and
produces an erection
31. Erectile dysfunction drugs may interact
with other drugs in the following ways:
• Nitrates and alpha-adrenergic blockers
–severe hypotension and CAUSE
–potentially serious cardiac events
• Ketoconazole, itraconazole, and erythromycin
may result in increased levels of vardenafil or
tadalafil
• Protease inhibitors, such as indinavir or
ritonavir, may cause increased tadalafil or
vardenafil levels
32. Adverse reactions to erectile
dysfunction drugs
• decreased supine blood pressure and cardiac
output
• increased risk of cardiovascular events, including
–myocardial infarction
–sudden cardiac death
–ventricular arrhythmias
–cerebrovascular hemorrhage
–transient ischemic attack
–Hypertension…
33. Other adverse effects
• headache
• dizziness
• flushing
• dyspepsia
• vision changes
• prolonged erections (more than 4 hours),
which can result in irreversible damage to
erectile tissue
• penile pain (with alprostadil).
34. Hormonal contraceptives
• Hormonal contraceptives inhibit ovulation.
• Contraceptives typically contain a combination
of hormones. e.g.
• ethinyl estradiol may be combined with
–Desogestrel
–Drospirenone
–Levonorgestrel
–Norethindrone
–norgestimate, or
–norgestrel.
35. .
• mestranol may be combined with
norethindrone
• Ethinyl estradiol or ethynodiol diacetate may
also be used alone as a contraceptive.
36. .
• The primary mechanism of action of
combination hormonal contraceptives
(estrogen and progestin) is the suppression of
gonadotropins which inhibits ovulation
• Estrogen suppresses secretion of follicle-
stimulating hormone, which blocks follicular
development and ovulation.
37. .
• Progestin suppresses the secretion of
luteinizing hormone, which prevents
ovulation, even if the follicle develops
• Progestin also thickens the cervical mucus;
this interferes with sperm migration and
causes endometrial changes that prevent
implantation of a fertilized ovum.
38. .
• The primary purpose for taking hormonal
contraceptives is the prevention of pregnancy
• The combination of ethinyl estradiol and
norgestimate is also used to treat moderate
acne in females younger than age 15.
39. Advantages
of combined oral contraceptives
• reliable and reversible
• reduced dysmenorrhoea and menorrhagia
• reduced incidence of premenstrual tension
• less symptomatic fibroids and functional ovarian
cysts
• less benign breast disease
• reduced risk of ovarian and endometrial cancer
• reduced risk of pelvic inflammatory disease
40. Drug interactions
• A patient taking drugs that interact with
hormonal contraceptives needs to use a
barrier contraceptive
41. Reduced effectiveness by interaction with
drugs that induce hepatic enzyme activity
• Carbamazepine
• Griseofulvin
• Modafinil
• Nelfinavir
• Nevirapine
• oxcarbazepine,
• Phenytoin
• Phenobarbital
43. .
• Cyclosporin and theophylline have an increased
risk of toxicity when taken with hormonal
contraceptives
• Atorvastatin may increase serum estrogen levels
• Prednisone increases the therapeutic and
possibly toxic effects of hormonal contraceptives
• Several herbal medications can affect serum
levels of hormonal contraceptives.
44. Adverse reactions to hormonal
contraceptives
• Potentially serious
–arterial thrombosis
–Thrombophlebitis
–pulmonary embolism
–myocardial infarction
–cerebral hemorrhage or thrombosis
–Hypertension
–gallbladder disease and
–hepatic adenomas
45. Other adverse reactions include
• acne
• bleeding or spotting between menstrual
periods
• bloating
• breast tenderness or enlargement
• changes in libido
• …..
47. Combined hormonal contraceptives should
be stopped if any of the following occur:
• sudden severe chest pain
• sudden breathlessness (or cough with blood-
stained sputum)
• unexplained swelling or severe pain in calf of
one leg
• severe stomach pain
• severe, prolonged headache
• …
48. .
• sudden partial or complete loss of vision
• sudden disturbance of hearing
• Dysphasia
• fainting attack or collapse
• first unexplained epileptic seizure
• numbness suddenly affecting one side or one
part of body
49. .
• hepatitis, jaundice, liver enlargement
• blood pressure above systolic 160mmHg or
diastolic 95 mmHg
• prolonged immobility after surgery or leg
injury
