Benign Prostatic Hyperplasia

Author: Nicole Lo RPh

Benign prostatic hyperplasia (BPH) is an overgrowth of tissues in the prostate, causing it to enlarge in size. As a result, the enlarged prostate places a greater pressure on the bladder, making it harder to urinate. This tissue overgrowth is non-cancerous and does not increase the risk for prostate cancer. Although it is common for elderly men to have BPH, most will not develop symptoms of BPH until age 50. Other risk factors for developing BPH include large waist size (also known as abdominal obesity) and lack of exercise.

Symptoms of BPH include:

- Difficulty with urination, especially with its initiation

- Slow or weak flow of urine

- Frequent night-time urination

- Incomplete emptying of the bladder upon urination, thereby increasing the risk of urinary tract infection and bladder stone development

Together, the symptoms listed above are classified as lower urinary tract symptoms (LUTS).

There are a few methods to diagnose BPH:

- Presence of LUTS and how bothersome these symptoms are to the patient – to determine if treatment is needed

- Digital rectal examination – to determine the size of the prostate

- Blood test – to assess the level of PSA (Prostate Specific Antigen), which is a useful estimate of the prostate size

- Urine test – to assess if there is a urinary tract infection, a common complication of BPH

There are a few lifestyle changes a patient can make to improve their BPH symptoms. One of which is to limit the fluid intake later on in the day, especially alcoholic or caffeinated beverages. If possible, the usage of drugs that can worsen LUTS should be limited as well. These include diuretics (or water pills), a type of medication used to treat high blood pressure, decongestants, used to relieve stuffy nose in over-the-counter cold remedies, and antihistamines, used to treat symptoms of allergy. A technique called bladder retraining may also help. This involves scheduling times for urination. For example, urinating every 3 hours instead of going whenever the urge is present. Another method to relieve the symptoms is pelvic floor exercise, which can strengthen the muscles around the pelvis to alleviate problems with controlling urination.

Treatment of BPH:

1) Drug therapy

i. Alpha-adrenergic blockers:

• Alfuzosin

• Doxazosin

• Silodosin

• Tamsulosin

• Terazosin

These medications relax the muscles near the prostate to relieve the pressure that is being put on the bladder and urethra, making it easier to urinate. They are all equally effective and can start to work within days to weeks. However, these agents have the potential to lower blood pressure. Therefore, patients with high blood pressure are advised to talk to their physician if they experience prolonged dizziness while taking both alpha-adrenergic blockers and antihypertensive medications. Furthermore, the combination of doxazosin or terazosin with phosphodiesterase-5 inhibitors (erectile dysfunction medications) should be avoided as it can lead to a significant decrease in blood pressure. To minimize the risk of dizziness, doxazosin and terazosin should be administered at bedtime. To increase the medications’ absorption, alfuzosin, tamsulosin and silodosin should be taken with food.

ii. 5-alpha-reductase inhibitors:

• Dutasteride

• Finasteride

These agents block the conversion of the male hormone, testosterone, to dihydrotestosterone, a chemical required for the enlargement of the prostate, resulting in the gradual reduction of its size. They are most effective in men with a larger prostate size but may take longer to start working compared to the alpha-adrenergic blockers. The onset of action may take weeks to months, but these medications can reduce the PSA level by 50% within 6 months of treatment and lower the risk of prostate cancer. Some patients will require a combination of alpha-adrenergic blocker and 5-alpha-reductase inhibitor for relief of their BPH symptoms. For these patients, once they have been on combination therapy for 6 to 12 months and their symptoms are eliminated, the alpha-adrenergic blocker may be stopped and restarted only if the symptoms return. An example of a combination product is called Jalyn, a single capsule containing dutasteride and tamsulosin.

iii. Phosphodiesterase-5 inhibitor –

• § Tadalafil

Although the use of this medication in BPH is less common, tadalafil works by relaxing the muscles of the bladder and prostate to improve urinary flow. As mentioned above, the combination of alpha-adrenergic blocker and phosphodiesterase-5 inhibitor should be avoided.

iv. Muscle relaxants –

• § Mirabegron

• § Solifenacin

As their name suggests, muscle relaxants relax the muscles of the bladder, thereby reducing the urge to urinate.

2) Natural health products

· African Prune Tree

· Lycopene

· Saw Palmetto

Of the 3 agents listed above, only African Prune Tree has demonstrated a beneficial effect on the symptoms of BPH in small clinical studies. It is generally well tolerated but more robust data is needed to recommend its usage in the treatment of BPH. Saw Palmetto and lycopene were shown to be no more effective than placebo.

3) Surgery

Surgeries are only used when the medications listed above do not work or when the patient cannot urinate at all. The most common surgical procedure for BPH is called the Transurethral Resection of Prostate (TURP), where a thin wire carrying an electric current is inserted into the prostate to remove parts of the organ’s tissues using electricity. It is the most effective at eliminating the BPH symptoms and is generally used for patients with moderately enlarged prostates. However, the symptoms can recur, which is why some patients may undergo this surgery more than once. Common side effects from this surgery include bleeding, infection and retrograde ejaculation (where semen goes into the bladder instead of exiting through the penis upon ejaculation). Nonetheless, the risk of these side effects is much lower in TURP compared to other surgical procedures for BPH.

References:

1) Canadian Cancer Society. Benign prostatic hyperplasia. 2021: https://cancer.ca/en/cancer-information/cancer-types/prostate/what-is-prostate-cancer/benign-prostatic-hyperplasia. Accessed 28 September 2021.

2) Gray, Jean. Therapeutic Choices. 5th ed., Canadian Pharmacists Association, 2007.

3) Lexicomp®. Lycopene (Natural Products Database). 2021: https://online.lexi.com/lco/action/doc/retrieve/docid/fc_rnp2/3750245?cesid=anDeHpILUEa&searchUrl=%2Flco%2Faction%2Fsearch%3Fq%3Dlycopene%26t%3Dname%26va%3Dlycopene. Accessed 28 September 2021.

4) Lexicomp®. Saw Palmetto (Natural Products Database). 2021: https://online.lexi.com/lco/action/doc/retrieve/docid/fc_rnp2/3750344?cesid=9NhAbBuLeqS&searchUrl=%2Flco%2Faction%2Fsearch%3Fq%3Dsaw%252520palmetto%26t%3Dname%26va%3Dsaw%252520palmetto. Accessed 28 September 2021.

5) Wilt, Timothy J, and Areef Ishani. “Pygeum africanum for benign prostatic hyperplasia.” Cochrane Database of Systematic Reviews, issue 1, 1998: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7032619. Accessed 28 September 2021.