Medications use in Benign Prostatic Hyperplasia…What you need to know

l   Alpha1 adrenoceptor blockers are now well established as the most common treatment for lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction

l Alpha1 adrenoceptor blockers are now well established as the most common treatment for lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction

Mr Pharmacist, I noticed my 70-year-old Uncle has been taking these medicines for sometime now. Kindly educate me on what they do. The medicines were Tab. Finasteride 5mg each night, Cap. Tamsulosin 400mcg each night, and Tab. Toleterodine 2mg twice daily. The medicines are for the management of Benign Prostatic Hyperplasia (BPH). I am quite sure that your Uncle was put on these medications by a Urologist.

The prostate gland makes a fluid that becomes part of the semen. Benign prostatic hyperplasia (BPH) involves enlargement of the prostate gland. The prostate enlargement in BPH is not malignant. BPH can impede the flow of urine.

Symptoms include frequent urge to urinate, getting up at night to urinate, difficulty urinating and dribbling of urine. BPH generally begins in a man as he ages. It evolves slowly, and most commonly only causes symptoms after 50. In BPH, the prostate gland grows in size.

It may compress the urethra which courses through the center of the prostate. This can impede the flow of urine from the bladder through the urethra to the outside. It can cause urine to back up in the bladder (retention) leading to the need to urinate frequently during the day and night.

Other common symptoms include a slow flow of urine, the need to urinate urgently and difficulty starting the urinary stream. More serious problems include urinary tract infections and complete blockage of the urethra, which may be a medical emergency and can lead injury to the kidneys.

BPH is managed by watchful waiting or surgically or medically. Finasteride is 5-alpha reductase inhibitor. The enzyme 5-alpha reductase metabolises testosterone into the more potent androgen, dihydrotestosterone.

The inhibition of testosterone metabolism leads to reduction in the size of the prostate with resulting improvement in urinary flow rate and in obstructive symptoms. The 4-year Proscar Long-term Efficacy and Safety Study (PLESS) showed that finasteride increased flow rate, decreased AUA SS, reduced prostate volume by 32%, lowered the risk of acute urinary retention by 57%, and reduced the need for BPH-related surgery by 55%. Alpha1-reductase inhibitors are medicines that can stop the prostate from growing further or even cause it to shrink. The medication works better in men with a larger prostate.

It can reduce the risk of urinary retention (not being able to empty the bladder) and the need for surgery. Most men will see an improvement within six months of starting treatment. A small percentage of men who alpha-reductase inhibitors such as Finasteride (or Dutasteride) will experience decreased sex drive or difficulty with erection or ejaculation.

This effect reverses when the drug is stopped and rarely should cause one to stop its use in treatment of BPH. The level of prostate specific antigen (PSA) a marker of prostate disorder, will decrease by about 50% in men who take alpha-reductase inhibitors such as Finasteride and therefore important to disclose this information particularly if one is having PSA testing to screen for prostate cancer.

It is useful to stress that 5-alpha rreductase inhibitors such as Finasteride are excreted in semen and use of a condom is recommended if the sexual partner is pregnant or likely to become pregnant. Women of childbearing potential should not handle crushed or broken tablets of Finasteride.

Tamsulosin is an alpha1-adrenoceptor blocker (antagonist). Alpha 1-adrenoceptor antagonists are considered to be appropriate treatment for all patients irrespective of prostate size.

Alpha1 adrenoceptor blockers are now well established as the most common treatment for lower urinary tract symptoms (LUTS) suggestive of benign prostatic obstruction (BPO), e.g., bladder outflow obstruction (BOO) associated with BPH. These selective alpha1 antagonists (blockers) such as Tamsulosin (or Alfuzosin) relax the smooth muscle in BPH producing an increase in urinary flow-rate and improvement in obstructive symptoms.

Even though molecules such as Tamsulosin have been developed to reduce the untoward effects of alpha adrenoceptor blockade (low blood pressure, dizziness, headache, blurred vision) by making them more specific for alpha1 adrenoceptor blockade, one may still experience such untoward effects and therefore the need to take it at night.

From the fore-going it is possible to have a combination therapy of for example, Finasteride (to shrink the enlarged prostate gland) and Tamsulosin (to relax the smooth muscle) and ultimately improve urine flow. The Medical Therapy of Prostatic Symptoms (MTOPS) study showed that alpha1-blockers improve BPH symptoms and increase time to disease progression but do not prevent overall progression (defined as acute urinary retention and the need for invasive therapy).

The MTOPS trial suggests that alpha1-blockers manage symptoms with a relatively rapid onset of action but do not prevent disease progression. This observation gave rise to a strategy of initially combining an alpha1-blocker and a 5-alpha-reductase inhibitor for a short duration (3 to 6 months) followed by withdrawal of the alpha-blocker and continuation of 5-alpha-reductase inhibitor monotherapy.

The client then enquired about the Tolterodine. About 30% of men aged 50–80 years have either moderate or severe LUTS, about half of these men will have a pattern of symptoms that overlaps with the syndrome of overactive bladder (OAB). OAB is a syndrome characterized by urgency with or without urge incontinence, usually with frequency and nocturia.

Like LUTS, the prevalence of OAB increases with age. OAB is managed with anticholinergic drugs such as Tolterodine (or Oxybutinin). Patients with BPH often have concomitant irritative voiding symptoms because of an overactive bladder (OAB). I believed that was the reason for the addition of Tolterodine 2mg to be taken twice daily.

The Tolterodine is therefore to manage urinary frequency, urgency and incontinence, neurogenic bladder instability, etc associated with overactive bladder. BPH remains a common problem. Medical therapy is usually the initial treatment of choice. Alpha-blockers (e.g. Doxazosin, Tamsulosin, Alfuzosin) provide symptomatic relief but do not prevent disease progression. Combination therapy with an alpha-blocker and a 5-alpha-reductase inhibitor is more effective than either monotherapy alone. Patients with both BPH and overactive bladder benefit from an anticholinergic addition to BPH therapy.

By Edward O. Amporful

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