BPH Flashcards
Main function of the prostate
to secrete fluid that becomes part of the seminal fluid carrying sperm.
What does the prostate depend on for development, maintenance of size and function?
The prostate is dependent on androgens (mainly testosterone) for development, maintenance of size and function.
Testosterone metabolism and role
Testosterone is metabolized to dihydrotestosterone (DHT) by 5 alpha-reductase. DHT is responsible for normal and hyperplastic growth (increase in the number of cells}. Benign prostatic hyperplasia (BPH) results from overgrowth of the stromal and epithelial cells of the prostate gland.
what contributes to lower urinary tract symptoms (LUTS
The layer of tissue surrounding the enlarged prostate stops it from expanding, causing the gland to press against or pinch the urethra. This contributes to lower urinary tract symptoms (LUTS) via direct bladder outlet obstruction and increased smooth muscle tone and resistance.
The bladder wall becomes thicker and irritated. It begins to contract even when it
contains small amounts of urine, causing frequent urination. Eventually, the bladder weakens and loses the ability to empty itself.
Diagnosis of BPH
Diagnosis requires
1- an assessment of the medical history (surgeries, trauma and current medications, including herbal and OTC drugs) and a physical exam
–> physical exam should include a digital rectal exam (DRE) to determine the size of the prostate and identify any lumps or nodules.
–> A urinalysis and serum prostate-specific antigen (PSA) are used to rule out conditions other than BPH.
PSA, a protein produced by prostate cells, is frequently increased in prostate cancer. It can increase when the prostate becomes larger due to BPH, though BPH is a benign (non-cancerous) condition and does not increase prostate cancer risk.
The signs and symptoms of BPH are mainly LUTS, which include:
- Hesitancy, intermittent urine flow, straining or a weak stream of urine.
- Urinary urgency and leaking or dribbling.
- Incomplete emptying of the bladder (bladder feels full).
- Urinary frequency, especially nocturia (urination at night).
- Bladder outlet obstruction.
What drugs can worsen BPH?
- Centrally-acting anticholinergics (e.g., benztropine)
- Drugs with anticholinergic effects: Antihistamines (e.g.,diphenhydramine) Decongestants (e.g.,pseudoephedrine) Phenothiazines (e.g.,prochlorperazine) TCAs (e.g.,amitriptyline)
- Caffeine
- Diuretics
- SNRls
- Testosterone products
Complications of BPH symptoms
Symptoms can significantly impact quality of life. BPH rarely causes more severe symptoms, but if the blockage is severe, the urine could back up into the kidneys and result in ACUTE RENAL FAILURE.
Urinary tract infections can also be present but are uncommon.
Why should all patients be referred to a prescriber before starting treatment?
Symptoms can be similar to prostate cancer, so all patients should be referred to a prescriber for an appropriate evaluation prior to starting treatment.
Treatment Principles
The severity of reported BPH symptoms guides selection of treatment.
Questionnaires:
such as the American Urological Association Symptom Score (AUASS)or the International Prostate Symptom Score (I-PSS),
–> are used to QUANTIFY symptoms. The scoring systems rate how bothersome the symptoms are, with higher scores indicating more severe symptoms.
Treatment options can include watchful waiting, pharmacologic therapy or surgical intervention.
Mild disease is generally treated with watchful waiting and yearly reassessments. Moderate/severe disease is generally treated with medications or a minimally invasive procedure or surgery, such as transurethral resection of the prostate (TURP).
Are natural products recommended in BPH?
The American Urological Association (AUA) guidelines do not recommend natural products for the treatment of BPH symptoms, though various natural products have been investigated.
Saw palmetto has been used for BPH, but it is unlikely to be effective based on contradictory and inconsistent data.
Lycopene is used for prostate cancer prevention, but there is no good evidence for use in BPH.
–> Pharmacists should not recommend natural products until the patient has seen a healthcare provider, as prostate cancer symptoms present similarly to BPH.
Drug treatment of BPH
Medications include alpha-blockers (selective and non- selective), used alone or in combination with a 5 alpha- reductase inhibitor.
The 5 alpha-reductase inhibitors work by decreasing prostate size, but they have a delayed onset.
They should not be used in men who have bladder outlet obstruction symptoms without prostate enlargement.
Alpha- blockers work quickly, but do not shrink the prostate. The two classes are often used together to get the benefits of each.
Peripherally-acting anticholinergic drugs used for overactive bladder (such as tolterodine) are sometimes a reasonable option for men without an elevated post void residual (PVR) urine and when LUTS are predominately irritative.
If anticholinergics are used, the PVR should be< 250 - 300 mL. These medications are discussed in the Urinary Incontinence chapter.
Another treatment option is the phosphodiesterase-5 (PDE-5) inhibitor tadalafil, with or without finasteride. This can be used in men with BPH alone, and can be an attractive option for men with both BPH and erectile dysfunction (ED).
5 alpha reductase inhibitor should not be used in:
They should not be used in men who have bladder outlet obstruction symptoms without prostate enlargement.
First line drugs in moderate to severe symptoms and whats their MOA?
Alpha-1 blockers are first-line treatment for moderate-to- severe symptoms.
They inhibit alpha-1 adrenergic receptors, causing relaxation of smooth muscle in the prostate and bladder neck.
–> This reduces bladder outlet obstruction and improves urinary flow.
Alpha blockers types and location
There are three types of alpha-I receptors. Alpha-IA receptors are primarily found in the prostate.
Alpha-lB and alpha-ID receptors are dominant in the heart and arteries.
What are the non-selective alpha 1 blockers?
The non-selective alpha-I blockers (terazosin, doxazosin) have more side effects (e.g., orthostasis, dizziness, headache) than the selective
What are the selective alpha 1 blockers?
selective alpha-IA blockers (tamsulosin, alfuzosin, silodosin).
lntraoperative Floppy Iris Syndrome
Alpha-blockers relax the smooth muscle of the prostate and bladder neck. The same receptors are present on the iris dilator muscle in the eye. Patients using alpha-blockers are at risk of developing intraoperative floppy iris syndrome (IFIS) during cataract surgery.
With alpha-I blockade, the iris becomes floppy, has a risk of prolapse and the pupils do not dilate well, complicating the procedure. If cataract surgery is planned, alpha-blocker treatment should be delayed until the surgery has been completed.
Non-selective alpha1 blockers
Doxazosin (Cardura, CarduraXL)
Terazosin
Doxazosin
Non selective alpha1 blocker used in BPH
Cardura, Cardura XL
IR: start 1 mg at BEDTIME ; TITRATE SLOWLY up to 4-8 mg at bedtime
XL: start 4 mg daily with breakfast; max 8 mg daily
Terazocin
Non selective alpha1 blocker used in BPH
at bedtime, titrate slowly
