Proscar (finasteride) is a prescription medication specifically formulated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men. As a 5-alpha-reductase inhibitor, it works at the hormonal level to address the underlying cause of prostate enlargement, offering a non-surgical approach to managing this common condition. By reducing the size of the enlarged prostate, Proscar effectively alleviates obstructive and irritative urinary symptoms, improving urinary flow and overall quality of life. Its well-established efficacy and safety profile, demonstrated through extensive clinical trials and decades of real-world use, make it a cornerstone of urological pharmacotherapy.

Features

• Active Ingredient: Finasteride 5 mg
• Drug Class: 5-alpha-reductase inhibitor (5-ARI)
• Administration: Oral tablet
• Standard Dosage: One 5 mg tablet daily
• Mechanism of Action: Selectively inhibits the conversion of testosterone to dihydrotestosterone (DHT)
• Onset of Action: Initial improvement in symptoms may be seen within 3-6 months, with continued improvement through 12-24 months of treatment
• Prescription Status: Requires a prescription from a licensed healthcare provider

Benefits

• Reduces Prostate Volume: Significantly decreases the size of the enlarged prostate gland, directly addressing the anatomical cause of BPH.
• Improves Urinary Function: Leads to a measurable increase in urinary flow rate and a reduction in symptoms of urinary obstruction, such as hesitancy, weak stream, and dribbling.
• Decreases Risk of Acute Urinary Retention: Long-term use has been shown to reduce the risk of developing acute urinary retention, a serious complication of BPH that often requires catheterization or surgery.
• Lowers Incidence of BPH-Related Surgery: Effective management with Proscar can reduce the need for invasive surgical interventions, such as transurethral resection of the prostate (TURP).
• Symptom Score Improvement: Provides clinically significant and sustained improvement in standardized symptom scores (e.g., IPSS - International Prostate Symptom Score).
• Convenient Dosing: A simple, once-daily oral regimen supports long-term treatment adherence.

Common use

Proscar is primarily indicated for the management of symptomatic benign prostatic hyperplasia (BPH) in adult men. It is used to treat the signs and symptoms of BPH, which include difficulty starting urination, weak urinary stream, straining to urinate, a feeling of incomplete bladder emptying, increased frequency of urination (especially at night, known as nocturia), and urgency. Treatment is intended for long-term use to control symptoms, reduce the risk of complications, and prevent disease progression. It is not indicated for use in women or children.

Dosage and direction

The recommended dosage of Proscar is one 5 mg tablet administered orally once a day, with or without food. The tablet should be swallowed whole; it should not be crushed or chewed, as this may increase the risk of absorption through the skin, which is a particular concern for pregnant women. Clinical improvement is not immediate. A minimum of six months of treatment is usually necessary to assess whether a therapeutic response has been achieved. Treatment may need to be continued long-term to maintain therapeutic benefits; cessation of therapy leads to a gradual return of prostate size and symptoms to pretreatment levels over a similar timeframe.

Precautions

• Pregnancy Warning (Women): Finasteride is contraindicated in women who are or may become pregnant. The tablet coating contains finasteride, which can be absorbed through the skin. Pregnant women or women who could become pregnant must not handle crushed or broken Proscar tablets due to the risk of absorption and potential teratogenic effects (abnormalities of the external genitalia) on a male fetus.
• Prostate-Specific Antigen (PSA) Monitoring: Proscar causes a decrease in serum PSA levels by approximately 50% in patients with BPH, even in the presence of prostate cancer. Any confirmed increase in PSA levels while on Proscar warrants further investigation to rule out prostate cancer. Healthcare providers should adjust the PSA value for this expected decrease when interpreting results for cancer screening.
• Blood Donation: Men being treated with Proscar should not donate blood until at least one month has passed after their final dose to prevent potential administration of blood containing finasteride to a pregnant female recipient.
• Hepatic Impairment: Caution should be exercised in the administration of Proscar in patients with liver function abnormalities, as finasteride is extensively metabolized in the liver, although no specific dosage adjustment is recommended.
• Digital Rectal Exams (DRE): Regular digital rectal exams should be performed on patients taking Proscar, as with all men at risk for prostate cancer, in conjunction with PSA monitoring.

Contraindications

• Hypersensitivity to finasteride or any other component of the Proscar formulation.
• Use in women, particularly those who are pregnant or of childbearing potential.
• Use in pediatric patients.

Possible side effect

As with all medications, Proscar can cause side effects, although not everybody gets them. Most side effects are related to the drug’s hormonal mechanism of action and are generally mild and transient.

• Very Common (≥1/10): Erectile dysfunction, decreased libido (sex drive).
• Common (≥1/100 to <1/10): Ejaculation disorders (e.g., decreased volume of ejaculate), breast enlargement and/or tenderness (gynecomastia).
• Uncommon (≥1/1,000 to <1/100): Skin rash, testicular pain.
• Rare (≥1/10,000 to <1/1,000): Allergic reactions, including lip swelling and skin rash.
• Post-Marketing Reports: Depression, male breast cancer, palpitations. A small number of men may report persistent sexual dysfunction (e.g., erectile dysfunction, diminished libido, ejaculatory disorders) that continues after discontinuation of therapy.

Drug interaction

Formal drug interaction studies have not revealed any clinically significant interactions with Proscar. However, the potential for interactions exists.

• Theoretical Interactions: Although not consistently demonstrated, potential interactions could occur with drugs that are extensively metabolized by the CYP3A4 enzyme system, as finasteride is a substrate of this enzyme. Caution is advised with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir).
• No Clinically Important Interactions: No interactions of clinical importance have been identified with antipyrine, atenolol, digoxin, propranolol, theophylline, or warfarin.
• Advisory: Patients should always inform their healthcare provider of all other medications they are taking, including prescription, over-the-counter, and herbal products.

Missed dose

If a dose of Proscar is missed, the patient should take it as soon as remembered on the same day. If the missed dose is not remembered until the next day, the patient should skip the missed dose and take only the usual daily dose. Do not take a double dose to make up for a forgotten tablet. Maintaining a consistent daily routine, such as taking the tablet at the same time each day, can help prevent missed doses.

Overdose

In clinical studies, doses of finasteride up to 400 mg per day for three months have been administered without observed adverse effects. There is no specific antidote for finasteride overdose. In the event of a suspected overdose, symptomatic and supportive treatment should be initiated. As finasteride is highly protein-bound, it is unlikely to be dialyzable.

Storage

• Store Proscar tablets at room temperature, between 20°C to 25°C (68°F to 77°F).
• Keep the medication in its original container, tightly closed, and out of reach of children and pets.
• Protect from light and moisture.
• Do not store in bathrooms or other areas with high humidity.
• Properly discard any expired or no longer needed medication.

Disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any new treatment. Never disregard professional medical advice or delay in seeking it because of something you have read here. The information provided is based on the manufacturer’s prescribing information and may not encompass all possible uses, directions, precautions, or side effects.

Reviews

• Clinical Trial Data (U.S. PLESS Study): A 4-year, double-blind, placebo-controlled study of over 3,000 men demonstrated that Proscar 5 mg daily led to a 57% reduction in the risk of acute urinary retention and a 55% reduction in the need for BPH-related surgery compared to placebo. A mean 2.5-point greater improvement in symptom score was also observed.
• Long-Term Extension Study (6-8 years): Data from long-term open-label extensions confirmed that the improvement in symptoms and flow rate was maintained throughout the treatment period.
• Real-World Evidence: Numerous post-marketing studies and urological practice reviews consistently support the efficacy of finasteride in managing BPH symptoms and preventing disease progression, confirming the findings of rigorous clinical trials in a broader patient population.