What is Proscar (Finasteride)?
Proscar (finasteride) is a 5-alpha-reductase inhibitor medication that is prescribed for the treatment of benign prostatic hyperplasia (an enlarged prostate) in men. It should not be prescribed to nor taken by women or children and should only be used by men to alleviate the common symptoms associated with an enlarged prostate and reduce their chances of requiring prostate surgery.
How is Proscar Used?
Proscar comes in tablet form and should be taken orally once per day. It may be taken with or without food. Take your medication as prescribed by your doctor regarding frequency as well as any other specific conditions that may apply.
This medication may be used solely by itself for treatment or may be prescribed alongside the alpha-blocker medication known as doxazosin for improved results.
The full results of taking Proscar (with or without doxazosin) may take up to six months to become fully apparent, and stopping the medication at any time will result in continued prostate growth.
Proscar should be stored at room temperature and should not exceed 86°F (30°C). Patients should ensure the medication is placed away from any exposure to light and remains well-sealed. It should not be stored in the bathroom and should not be exposed to moisture.
Keep this medication out of reach of pets and children at all times.
Pregnant women or women that may potentially be pregnant should not handle broken or crushed Proscar tablets due to the risk of absorption that may negatively impact the development of a male fetus. This medication is capable of being absorbed through the skin and should be washed away with soap and water immediately after making contact.
If your medication needs to be disposed of for some reason, please contact your local pharmacist or waste disposal company for instructions regarding safe disposal. Proscar should not be thrown in with one’s regular trash, poured down the sink, or flushed down the toilet.
Proscar is prescribed for the treatment of benign prostatic hyperplasia, the condition of having an enlarged prostate.
In lower doses, finasteride is marketed as Propecia and prescribed for the treatment of androgenetic alopecia (i.e., male pattern hair loss).
It may occasionally be prescribed off-label for use in females struggling with hair loss, but this is typically avoided due to the potential health risks for women in their child-bearing years. Generic, lower-dosage versions of this medication have occasionally been used off-label for the treatment of undesired facial hair growth in women.
How Does Proscar Work?
Proscar works to alleviate the symptoms associated with benign prostatic hyperplasia by shrinking the enlarged prostate of the patient. It does this due to the function of its active ingredient (finasteride) being a 5-alpha reductase inhibitor.
5-alpha reductase inhibitors work by suppressing (i.e., inhibiting) the enzyme known as “5-alpha reductase.” This enzyme exists within the body in the prostate, the skin, and one’s liver. Its purpose is to convert testosterone into dihydrotestosterone, or DHT. Dihydrotestosterone is a male sex hormone that is associated with acne, prostate growth, and facial hair growth as well as with male pattern baldness. It exists in both men and women, and 5-alpha reductase inhibitors are designed to decrease the production of DHT within the human body.
Proscar is available as a 5 mg tablet that is blue in color, film-coated, apple-shaped, and comes printed with the brand name of “PROSCAR” on one side and “MSD 72” on the other.
If a patient has managed to overdose or has taken an excessive amount of Proscar, they are advised to contact their local Poison Control Center or seek out emergency medical assistance.
Commonly, ingesting an excessive amount of Proscar will result in a higher likelihood of experiencing adverse effects. Some of these adverse reactions include:
- an increase in breast size
- an increase in breast tenderness
- ejaculation disorder
- difficulty getting an erection
- difficulty maintaining an erection
- decreased libido
Taking a medication such as Proscar may cause certain patients to experience adverse side effects during treatment or after stopping the medication.
The most common side effects of taking Proscar are as follows:
- decreased libido
- erectile dysfunction
- decreased volume of semen during ejaculation
- difficulty achieving orgasm
- testicular pain
- increased hair growth
The most serious potential side effects of taking this medication include the following and should be reported to your doctor immediately:
- blood in the patient’s ejaculate
- breathing difficulties
- breast enlargement
- breast pain
- lumps in the breast
- muscle pain
- muscle weakness
- nipple discharge
- ongoing or severe nausea
- reduced semen quality or infertility
- swelling of the lips, face, throat, or tongue
- tenderness of the breast
- testicular pain
- other unusual breast symptoms or changes
- symptoms of depression
- decreased interest in hobbies or other enjoyable activities
- impaired concentration
- sleep difficulties or changes in sleep habits
- suicidal ideation
- weight gain or loss
- symptoms of an allergic reaction
- rash on the skin
- swelling of the mouth, tongue, or lips
Additionally, even after stopping the use of Proscar, some patients may experience lingering side effects that should be discussed with their doctor. The most common of these symptoms include the following:
- decreased libido even after stopping the medication
- erectile dysfunction or other sexual difficulties
- ongoing problems associated with ejaculation
Please contact your doctor for further information if you experience any additional side effects and have any concerns.
Warnings & Precautions
Patients taking Proscar should inform their prescribing physician of any allergies, current medications, or preexisting health conditions to ensure that this medication does not place them at an increased risk of developing certain side effects and serious health conditions. Individuals with preexisting liver conditions or a history of prostate cancer should consult with their doctor about the safety of using Proscar for treatment as well as weigh the risks versus the benefits of this medication.
Proscar is processed in the liver, and individuals taking this medication should inform their doctor if they have any preexisting liver conditions or a family history of liver issues. Certain liver diseases may cause the medication to be processed more slowly, leading to a buildup of Proscar within the body and an increased risk of adverse effects from high levels of the medication. Consult with your doctor if you are at risk of this potentially occurring, and your doctor may recommend adjusting your dosage size and instructions.
The use of Proscar has been associated with an increased risk of patients developing a high-grade form of prostate cancer in some cases. Additionally, patients who have had or currently have prostate cancer may experience a worsening of the condition if receiving treatment with this medication. Be sure to discuss all health risks, medications, your family health history, and any preexisting medical conditions that may be impacted by this medication with your doctor before beginning treatment with Proscar.
Prostate Cancer Screening
Proscar has been found to impact the results of the blood test used in detecting the presence of prostate cancer. Specifically, it may skew the results when trying to detect accurate readings of a patient’s PSA (prostatic-specific antigen) levels. Patients taking this medication should inform their doctor as well as any applicable laboratory personnel that they are taking this medication before testing.
Male Breast Cancer
Due to the hormonal changes caused by the function of Proscar as a 5-alpha reductase inhibitor, this may result in an increased risk of men taking this medication developing male breast cancer stemming from an imbalance in the patient’s androgen to estrogen ratio. Individuals taking Proscar should be prompt in reporting any changes in breast tissue, including issues such as nipple discharge, pain, or lumps.
There are no known food interactions associated with Proscar. This medication may be taken with or without food.
This medication should not be used during pregnancy and is not prescribed for use in women even when they are not pregnant or planning on becoming pregnant.
It is not known whether Proscar is passed through breast milk. However, this medication is not prescribed for use in women and should not be used by any woman that is breastfeeding. Breastfeeding mothers should also avoid touching broken or crushed Proscar tablets due to the risk of absorption and lack of study regarding Proscar in a woman’s system and how it may or may not be passed through breastmilk.
This medication is not prescribed for use in children, and its efficacy and safety have not been studied in this age group.
Speak to your doctor about any medications or herbal supplements you are currently taking before beginning treatment with Proscar. Studies have not identified any significant interactions between Proscar and any other prescription or over-the-counter medications or herbal supplements. However, this does not mean no such interactions exist.
The following medications and herbal supplements may result in decreased levels of Proscar due to the increase in the breakdown of the medication within the liver:
- John’s wort
The following medications may result in an increased amount of Proscar being present in a patient’s blood:
If you believe Proscar may be interacting with another medication or herbal supplement you are taking, please discuss any concerns you may have with your doctor or a trusted pharmacist.
For patients who are unable to take Proscar or experiencing significant adverse side effects, alternative medications may be used to treat some of the associated conditions for which this medication is commonly prescribed.
The main alternative to Proscar is the medication known as dutasteride. This medication is very similar in function to Proscar but comes in a different dosage. It is also known to have adverse interactions with certain other medications. Additionally, dutasteride is commonly paired with Flomax (tamsulosin) for the treatment of an enlarged prostate, so this is another medication that will need to be taken into account if a patient needs to change their primary BPH medication to dutasteride.
Please speak to your prescribing physician if you are experiencing any significant adverse side effects or other concerns that may necessitate a change in your medication.