Finasteride
Medicine Type :
Allopathy
Allopathy
Prescription Type:
Prescription Required
Prescription Required
Approval :
DCGI (Drugs Controller General of India)
DCGI (Drugs Controller General of India)
Schedule
Schedule H
Schedule H
Pharmacological Class:
5-Alpha-Reductase Inhibitors, Therapy Class:
Antiandrogenic agent, Approved Countries
India,the United States, Canada, the United Kingdom, Australia, Germany, France, Japan and Brazil.
Finasteride is an antiandrogenic agent belonging to the pharmacological class of 5-Alpha-Reductase Inhibitors.
Finasteride is approved for use by the FDA for treating benign prostate hyperplasia and androgenic alopecia (male pattern hair loss) in men.
After oral intake, Finasteride rapidly absorbs, attaining peak concentrations within 1-2 hours. Metabolism occurs extensively in the liver, primarily through CYP3A4 enzymes, and the body eliminates it through urine and faces due to its high distribution volume.
Finasteride is well tolerated and has only very mild sexual side effects such as erectile dysfunction, low decreased libido, and ejaculation disorder.
Finasteride is available in the form of oral tablets.
The molecule is available in India, the United States, Canada, the United Kingdom, Australia, Germany, France, Japan and Brazil.
Finasteride is an antiandrogenic agent belonging to the pharmacological class of 5-Alpha-Reductase Inhibitors.
Finasteride actively inhibits the type II 5α-reductase, a specific enzyme within cells that converts testosterone to DHT, an androgen. It predominantly targets the type II isozyme in humans, observed in native tissues like the scalp and prostate. Men experiencing male pattern hair loss show heightened DHT levels in balding scalp areas with miniaturized hair follicles. By administering finasteride, both scalp and serum DHT concentrations decrease in these individuals. The medication potentially disrupts a critical element in the development of androgenetic alopecia among genetically predisposed patients.
Data duration of Finasteride action lasts about 24 hr after each dose.
The onset of Finasteride action typically occurs within three to six months.
The Data of Tmax of Finasteride is typically within 1-2 hours after oral administration.
The Data of Cmax of Finasteride is typically approximately 1-2 hours after oral administration.
Finasteride is available in the form of oral tablets.
Tablets: To be swallowed whole with water/liquid. Do not chew, crush or break it.
As the physician recommends, take the medication orally once daily; it can be taken with or without food as directed.
Hair loss: At the crown and mid-scalp, male pattern alopecia (androgenetic alopecia) occurs. Only males who are adults should use it.
In Treatment of Hair Loss
Finasteride prevents testosterone from being converted to dihydrotestosterone, which is the cause of hair loss, by inhibiting the 5-alpha-reductase enzyme. Inhibiting hair loss and promoting regrowth is achieved by lowering dihydrotestosterone levels. This procedure encourages hair growth while stopping significant hair loss or thinning. Regular use can improve looks, self-esteem, and mood. Consistent use is essential for long-term advantages, making it a safe option for maintaining and regrowing hair.
Finasteride is indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men who have an enlarged prostate to alleviate symptoms, lower the chance of developing acute urine retention, and lower the likelihood of requiring surgery, such as prostatectomy and transurethral resection of the prostate (TURP). For a maximum of 26 weeks, a combination medication containing tadalafil is also used to treat BPH symptoms.
In male patients, finasteride is also indicated for treating male pattern hair loss, generally referred to as androgenetic alopecia, hereditary alopecia, or common male baldness.
Orally: Finasteride is usually administered orally as a tablet, once daily, with or without food. The recommended dose for treating benign prostatic hyperplasia (BPH) is 5 milligrams daily, while for androgenetic alopecia (male pattern hair loss), the standard amount is 1 milligram daily. It is best to follow the physician's prescribed schedule for regular and evenly spaced intervals because the dose and duration of therapy are individualized per specific conditions to achieve the most effective and successful treatment outcome.
The dosage and duration of treatment should be as per the treating physician's clinical judgment.
Tablets: 1mg or 5mg
Finasteride is available in the form of oral tablets.
Dose Adjustment in Adult Patients:
Benign Prostatic Hyperplasia Proscar: 5 mg PO qDay; evaluate responses after 6 months to 12 weeks
Androgenic Hair Loss (Only in Men): 1 mg PO qDay of Finasteride for a minimum of three months
Off-label female hirsutism (5 mg PO qDay)
There aren't specific dietary restrictions for Finasteride. However, maintaining a balanced diet rich in nutrients supports general health, including hair health.
Also, limit the intake of alcohol, as it may potentially exacerbate side effects like dizziness or drowsiness.
The dietary restriction should be individualized as per patient requirements.
Finasteride may be contraindicated in the following conditions:-
- Anyone who has previously experienced hypersensitivity to any of the product's constituents.
- Pregnant women or those who may get pregnant.
Exercise caution in individuals with obstructive uropathy. Monitor patients closely if they exhibit significant urinary volume retention or reduced urinary flow.
Be cautious when using in individuals with liver disease.
This medication might reduce serum PSA levels in individuals with prostate cancer. Elevations in PSA levels while on finasteride warrant thorough assessment for possible prostate cancer, regardless of PSA values within the normal range.
Women who are pregnant or potentially pregnant ought to refrain from broken or crushed tablets and their partner's semen, as these substances can harm the development of the fetus.
Rare instances of male breast cancer have been reported with this medication. Any breast changes like tenderness, enlargement, lumps, or discharge should be promptly informed to a healthcare provider.
Alcohol Warning
It is unsafe to consume Finasteride with alcohol.
Breast Feeding Warning
Avoid use during breastfeeding.
Pregnancy Warning
It is not recommended for use during pregnancy.
Food Warning
There are no specific food warnings.
The adverse reactions related to Finasteride can be categorized as
- Common Adverse Effects: Erectile dysfunction, decreased libido, ejaculation disorder
- Less Common Adverse Effects: Skin rash or itching. depression or anxiety
- Rare Adverse Effects: Breast tenderness, rash.
Post-marketing experience:
Neoplasms: Breast cancer in men
Breast diseases: Enlargement and soreness in the breasts
Nervous system/psychiatric: Suicidal thoughts and actions, urticaria, depression
Rash, pruritus, and angioedema (including swelling of the lips, tongue, throat, and face) are signs of hypersensitivity reactions.
Reproductive system: Male infertility or poor seminal quality (normalization or improvement of seminal quality has been reported after discontinuing finasteride); testicular pain, hematospermia, and blood in semen; sexual dysfunction that persisted after treatment discontinuation, including erectile dysfunction, libido disorders, ejaculation disorders, and orgasm disorders.
The clinically relevant drug interactions of Finasteride are briefly summarized here.
There are currently no known medication interactions that are clinically significant. Finasteride does not affect the system of enzymes that metabolize drugs linked to cytochrome P450. Antipyrine, digoxin, glyburide, propranolol, theophylline, and warfarin are tested on humans; no interactions were discovered.
Finasteride doses were used concurrently with ACE inhibitors, acetaminophen, alpha-blockers, benzodiazepines, cardiac nitrates, diuretics, H2 antagonists, beta-blockers, calcium-channel blockers, HMG-CoA reductase inhibitors, prostaglandin synthetase inhibitors (NSAIDs), and quinolones in clinical studies, without evidence of clinically significant adverse interactions. (although specific interaction studies have yet to be carried out).
The most common side effects of Finasteride include:
Ejaculation disorder
Low sexual desire ( libido)
Impotence (erectile dysfunction)
Trouble having an orgasm
Pregnancy
Pregnancy Category X (FDA); The risks outweigh the potential benefits. Safer alternatives exist.
It is contraindicated for women who are pregnant or may become pregnant to use finasteride tablets.
Animal data
In rat studies, oral finasteride during fetal development showed a dose-dependent rise in male offspring having hypospadias, genital changes, and decreased weights at doses 0.1 to 86 times higher than the human recommended dose. Finasteride inhibits 5α-reductase, which is crucial for normal male genitalia development. Pregnant patients or those planning pregnancy while using this drug should understand its potential risk to male fetuses. Women shouldn't handle crushed tablets or semen from men taking finasteride. Semen exposure from men on finasteride showed concentrations 50 to 100 times less than a dose that did not affect male hormones.
Reproductive potential
Females: Avoid use.
Males: In healthy male volunteers treated for 24 weeks, semen analysis showed no significant effects on sperm parameters except for a 0.6 mL (22.1%) decrease in ejaculate volume and total sperm per ejaculate. These changes were reversible upon stopping therapy, typically returning to baseline within 84 weeks. Postmarketing, male infertility or reduced semen quality occurred but often improved after stopping finasteride.
- Nursing Mothers
It is not recommended for usage in females.
It is unknown if human milk contains finasteride excretion.
- Pediatric Use
As per the FDA, safety and effectiveness in the pediatric population have not been established.
- Geriatric Use
Studies on the clinical efficacy of finasteride only involved participants older than 65. Finasteride dosage adjustments for older patients are not required, according to the pharmacokinetics of finasteride 5 mg. Nevertheless, finasteride's effectiveness in older adults has yet to be established.
Dose Adjustment in Kidney Impairment Patients:
Renal impairment: No dosage adjustment is necessary.
Dose Adjustment in Hepatic Impairment Patients:
Patients with liver function disorders should take caution while administering finasteride tablets because the drug is extensively metabolized in the liver.
The physician should be vigilant about the knowledge pertaining to the identification and treatment of overdosage of Finasteride.
Overconsumption of Finasteride is unknown. There is no specific antidote or treatment for excessive intake of Finasteride. However, immediate medical attention is essential. Finasteride should be terminated immediately when an overdose is suspected or if any unusual symptoms occur after intake.
Clinical trials indicated that single doses of finasteride at 400 mg and multiple doses at 80 mg/day for three months didn't cause adverse effects. There's no recommended specific treatment for an overdose with Finasteride at this time.
Pharmacodynamics:
After taking finasteride orally, serum DHT levels are quickly reduced by about 65% in less than 24 hours. While there is a modest increase (about 15%) from baseline in testosterone and estradiol, these levels are still within normal physiological parameters. This drug has no androgen receptor affinity and no androgenic, antiandrogenic, estrogenic, antiestrogenic, or progestational actions. Finasteride also doesn't substantially change LH, FSH, or prolactin levels. Studies showed that it did not affect gonadotropin-releasing hormone-induced LH and FSH responses, suggesting that the hypothalamic-pituitary-testicular axis remained unaltered. The blood levels of cortisol, thyroid-stimulating hormone, and thyroxine did not change when finasteride was administered.
Pharmacokinetics:
Absorption
After ingestion, finasteride has a 65% bioavailability. Its onset varies; it takes over three months to address hair loss and approximately six months to treat benign prostatic hyperplasia (BPH). This medicine reaches its peak plasma time two to six hours after dosing.
Distribution
Plasma proteins bind about 90% of the finasteride that is in circulation. Finasteride has a slow accumulation phase following several doses.
It has been found that finasteride crosses the blood-brain barrier.
Vd: 76 L
Metabolism
Finasteride undergoes primary metabolism through hepatic CYP3A4 enzymes, generating crucial active metabolites like t-butyl side chain monohydroxylate and monocarboxylic acid metabolite, essential for its pharmacological effects.
Elimination
Upon ingesting finasteride orally, humans excreted 39% of the dosage as metabolites (basically, no unaltered medication was eliminated from the urine) and 57% of the entire dosage as faeces. About 165 mL/min is the plasma clearance.
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- Mysore V. Finasteride and sexual side effects. Indian Dermatol Online J. 2012 Jan;3(1):62-5. Doi: 10.4103/2229-5178.93496. PMID: 23130269; PMCID: PMC3481923.
- Anitha B, Inamadar AC, Ragunatha S. Finasteride-its impact on sexual function and prostate cancer. J Cutan Aesthet Surg. 2009 Jan;2(1):12-6. doi: 10.4103/0974-2077.53093. PMID: 20300365; PMCID: PMC2840927.
- Mella JM, et al. Efficacy and safety of finasteride therapy for androgenetic alopecia: a systematic review. Arch Dermatol. 2010 Oct;146(10):1141-50. doi: 10.1001/archdermatol.2010.256. PMID: 20956649.
- https://www.ncbi.nlm.nih.gov/books/NBK513329/
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- https://www.accessdata.fda.gov/drugsatfda_docs/
- https://www.medicines.org.uk/emc/product/3493/pil
Published on: 23 Nov 2023 6:24 AM GMT