Should I hold finasteride (a 5-alpha-reductase inhibitor) in cases of urinary retention?

From the Guidelines

You should not automatically hold finasteride in cases of urinary retention, as it is actually beneficial in reducing the risk of subsequent acute urinary retention and the need for BPH-related surgery, with the absolute benefit increasing with rising prostate volume or serum PSA, as shown in studies such as 1. Finasteride, a 5-alpha-reductase inhibitor, helps treat benign prostatic hyperplasia (BPH) which is often a cause of urinary retention in men. It works by blocking the conversion of testosterone to dihydrotestosterone (DHT), which reduces prostate size over time (typically 3-6 months for full effect). In acute urinary retention, other interventions like catheterization are needed immediately, but finasteride should generally be continued as part of the long-term management plan. However, if the urinary retention is suspected to be caused by something other than BPH, the medication should be evaluated in context of the overall treatment plan. Some key points to consider include:

• The typical dose for BPH is 5mg daily, as mentioned in studies such as 1.
• Patients should understand that while finasteride helps prevent progression of BPH symptoms, it works gradually and is not effective for immediate relief of acute retention.
• If a patient is experiencing urinary retention, they should seek immediate medical attention for proper evaluation and management while continuing their prescribed finasteride unless specifically instructed otherwise by their healthcare provider. It's also worth noting that finasteride has been shown to be effective in partially relieving symptoms, although it may be less effective for this purpose than alpha-blocker therapy, as discussed in 1. Overall, the benefits of continuing finasteride in cases of urinary retention, particularly when caused by BPH, outweigh the potential risks, and it should be continued as part of the long-term management plan, unless contraindicated by the patient's specific condition or other factors, as supported by studies such as 1.

From the FDA Drug Label

The improvement in BPH symptoms was seen during the first year and maintained throughout an additional 5 years of open extension studies. In A Long-Term Efficacy and Safety Study, efficacy was also assessed by evaluating treatment failures Treatment failure was prospectively defined as BPH-related urological events or clinical deterioration, lack of improvement and/or the need for alternative therapy. BPH-related urological events were defined as urological surgical intervention and acute urinary retention requiring catheterization. Compared with placebo, finasteride tablets was associated with a significantly lower risk for acute urinary retention or the need for BPH-related surgery [13.2% for placebo vs 6. 6% for finasteride tablets; 51% reduction in risk, 95% CI: (34 to 63%)]. Compared with placebo, finasteride tablets was associated with a significantly lower risk for surgery [10.1% for placebo vs 4.6% for finasteride tablets; 55% reduction in risk, 95% CI: (37 to 68%)] and with a significantly lower risk of acute urinary retention [6.6% for placebo vs 2. 8% for finasteride tablets; 57% reduction in risk, 95% CI: (34 to 72%)]

Finasteride reduces the risk of acute urinary retention.

• The risk of acute urinary retention was reduced by 57% in patients treated with finasteride tablets compared to patients treated with placebo.
• Finasteride tablets are indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to reduce the risk of acute urinary retention. Therefore, there is no need to hold finasteride in cases of urinary retention, as it may actually help reduce the risk of acute urinary retention 2, 2, 2.

From the Research

Urinary Retention and Finasteride

• Urinary retention is the inability to voluntarily void urine, and it can be acute or chronic 3, 4.
• The most common cause of urinary retention is benign prostatic hyperplasia (BPH), which can be treated with medications such as finasteride, a 5-alpha-reductase inhibitor 5, 6.
• Finasteride works by inhibiting the conversion of testosterone to dihydrotestosterone, which helps to reduce prostate size and alleviate symptoms of BPH 5, 6.

Holding Finasteride in Urinary Retention

• There is no direct evidence to suggest that finasteride should be held in cases of urinary retention 3, 4, 7.
• However, finasteride is used to treat BPH, which is a common cause of urinary retention, and it may help to reduce the risk of acute urinary retention and BPH-related surgery 5, 6.
• The decision to hold finasteride in cases of urinary retention should be made on a case-by-case basis, taking into account the individual patient's medical history and the underlying cause of the urinary retention 3, 4, 7.

Key Points to Consider

• Finasteride is effective in reducing the risk of BPH-related complications, including acute urinary retention and BPH-related surgery 5, 6.
• The medication should be used under the guidance of a healthcare professional, and patients should be monitored for any adverse effects 6.
• In cases of urinary retention, the underlying cause should be determined and treated accordingly, and finasteride may be continued or discontinued based on the individual patient's needs 3, 4, 7.