Description

Simple

A medication used to treat prostate cancer and hair loss in men.

Clinical

An antiandrogenic compound that is used for the treatment of symptomatic benign prostatic hyperplasia (BPH) and male pattern hair loss in adult males by inhibiting Type II 5-alpha reductase.

Overview

Finasteride is a synthetic 4-azasteroid compound [13] and specific inhibitor of steroid Type II 5α-reductase, which is an intracellular enzyme that converts the androgen testosterone into 5α-dihydrotestosterone (DHT). It works in a similar fashion as [dutasteride], which is another 5-alpha-reductase inhibitor, by exerting antiandrogenic effects. Finasteride is an orally active drug that was first approved by the FDA in 1992 for the treatment of benign prostatic hyperplasia to improve symptoms and reduce the risk for acute urinary retention or the need for surgical procedures.[12,13] In 1998, it was approved by the FDA to treat male pattern hair loss.[12] Finasteride is commonly marketed under the brand names Propecia and Proscar to be used aloneo or in combination with [doxazosin], an alpha-blocker.

Both benign prostatic hyperplasia and androgenic alopecia are androgen-dependent disorders that are characterized by _in situ_ high levels of DHT.[Read more

Pharmacology

Indication

Indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to improve symptoms, reduce the risk of acute urinary retention, and reduce the risk of the need for surgery including transurethral resection of the prostate (TURP) and prostatectomy.[ Read more

Pharmacodynamic

Finasteride is an antiandrogenic compound that works by suppressing the production of serum and intraprostatic dihydrotestosterone (DHT) in men via inhibiting the enzyme responsible for the biosynthesis of DHT. The maximum effect of a rapid reduction in serum DHT concentration is expected to be obse... Read more

Mechanism of action

Finasteride acts as a competitive and specific inhibitor of Type II 5α-reductase, a nuclear-bound steroid intracellular enzyme primarily located in the prostatic stromal cell that converts the androgen testosterone into the more active metabolite, 5α-dihydrotestosterone (DHT).[ Read more

Absorption

Finasteride is well absorbed following oral administration [10] and displays a slow accumulation phase after multiple dosing.[lablel]... Read more

Protein binding

Approximately 90% of circulating finasteride is bound to plasma proteins.[13]

Volume of distribution

The volume of distribution is 76 L at steady state, ranging from 44 to 96 L. Finasteride has been shown to cross the blood brain barrier but does not appear to distribute preferentially to the CSF.[ Read more

Clearance

In healthy young subjects (n=15), the mean plasma clearance of finasteride was 165 mL/min with the range between 70 and 279 mL/min.[13]

Half life

In healthy young subjects receiving finasteride, the mean elimination half-life in plasma was 6 hours ranging from 3 to 16 hours. In elderly patients over the age of 70 years, the half-life is prolonged to 8 hours.[ Read more

Route of elimination

In healthy subjects, about 32-46% of total oral dose of finasteride was excreted in the urine in the form of metabolites while about 51-64% of the dose was excreted in the feces. In patients with renal impairment, the extent of urinary excretion of finasteride is expected to be decreased while the f... Read more

Toxicity

**LD50**

Oral LD50 is about 418 mg/kg in rats[MSDS] and there have been cases of lethality in rats receiving a single oral dose of 400 mg/kg in males and 1000 mg/kg in females.[13]

**... Read more

Adverse Effects

Contraindications

  • Route:
    • Oral
  • Hypersensitivity:
    • true
  • Regions: US
  • Route:
    • Oral
  • Sex Group: female
  • Regions: US
  • Regions: US
  • Patient Conditions:
      • Name: Pregnancy
      • Drugbank Id: DBCOND0018394

Food Interactions

  • Take without regard to meals.

Interactions

Type in a drug name to check for interaction with Finasteride
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  • Paracetamol(acetaminophen)
  • Paxil(paroxetine)
  • Pamelor(nortriptyline)
  • Panadol(acetaminophen)
  • Patanol(olopatadine ophthalmic)
  • Pataday(olopatadine ophthalmic)
  • Parnate(tranylcypromine)
  • Pazeo(olopatadine ophthalmic)
1-(3-Mercapto-2-Methyl-Propionyl)-Pyrrolidine-2-Carboxylic Acid
The risk or severity of hypertension can be increased when Finasteride is combined with 1-(3-Mercapto-2-Methyl-Propionyl)-Pyrrolidine-2-Carboxylic Acid.
1-benzylimidazole
The risk or severity of hypertension can be increased when Finasteride is combined with 1-benzylimidazole.
2,5-Dimethoxy-4-ethylamphetamine
The therapeutic efficacy of Finasteride can be decreased when used in combination with 2,5-Dimethoxy-4-ethylamphetamine.
2,5-Dimethoxy-4-ethylthioamphetamine
The therapeutic efficacy of Finasteride can be decreased when used in combination with 2,5-Dimethoxy-4-ethylthioamphetamine.
4-Bromo-2,5-dimethoxyamphetamine
The therapeutic efficacy of Finasteride can be decreased when used in combination with 4-Bromo-2,5-dimethoxyamphetamine.
4-Bromo-2,5-dimethoxyphenethylamine
The therapeutic efficacy of 4-Bromo-2,5-dimethoxyphenethylamine can be decreased when used in combination with Finasteride.
4-Methoxyamphetamine
The risk or severity of hypertension can be increased when Finasteride is combined with 4-Methoxyamphetamine.
5-methoxy-N,N-dimethyltryptamine
The risk or severity of hypertension can be increased when Finasteride is combined with 5-methoxy-N,N-dimethyltryptamine.
Abatacept
The metabolism of Finasteride can be increased when combined with Abatacept.
Abediterol
The risk or severity of hypertension can be increased when Finasteride is combined with Abediterol.
Acalabrutinib
The metabolism of Finasteride can be decreased when combined with Acalabrutinib.
Acebutolol
Finasteride may decrease the antihypertensive activities of Acebutolol.
Aceclofenac
The risk or severity of hypertension can be increased when Finasteride is combined with Aceclofenac.
Acemetacin
The risk or severity of hypertension can be increased when Finasteride is combined with Acemetacin.
Acepromazine
The risk or severity of hypertension can be increased when Finasteride is combined with Acepromazine.
Acetylsalicylic acid
The risk or severity of hypertension can be increased when Acetylsalicylic acid is combined with Finasteride.
Adalimumab
The metabolism of Finasteride can be increased when combined with Adalimumab.
Adrafinil
The risk or severity of hypertension can be increased when Finasteride is combined with Adrafinil.
Afelimomab
The metabolism of Finasteride can be increased when combined with Afelimomab.
Alclofenac
The risk or severity of hypertension can be increased when Finasteride is combined with Alclofenac.
13 References
  1. 1 . Smith AB, Carson CC: Finasteride in the treatment of patients with benign prostatic hyperplasia: a review. Ther Clin Risk Manag. 2009 Jun;5(3):535-45. Epub 2009 Jul 12.PubMed: 19707263
  2. 2 . Agamia NF, Abou Youssif T, El-Hadidy A, El-Abd A: Benign prostatic hyperplasia, metabolic syndrome and androgenic alopecia: Is there a possible relationship? Arab J Urol. 2016 Feb 23;14(2):157-62. doi: 10.1016/j.aju.2016.01.003. eCollection 2016 Jun.PubMed: 27489744
  3. 3 . Vaughan ED: Long-Term Experience with 5-alpha-Reductase Inhibitors. Rev Urol. 2003;5 Suppl 4:S28-33.PubMed: 16985960
  4. 4 . Bhargava S: Increased DHT levels in androgenic alopecia have been selected for to protect men from prostate cancer. Med Hypotheses. 2014 Apr;82(4):428-32. doi: 10.1016/j.mehy.2014.01.016. Epub 2014 Jan 26.PubMed: 24548754
  5. 5 . Mysore V: Finasteride and sexual side effects. Indian Dermatol Online J. 2012 Jan;3(1):62-5. doi: 10.4103/2229-5178.93496.PubMed: 23130269
  6. 6 . McClellan KJ, Markham A: Finasteride: a review of its use in male pattern hair loss. Drugs. 1999 Jan;57(1):111-26. doi: 10.2165/00003495-199957010-00014.PubMed: 9951956
  7. 7 . Wilson JD: The pathogenesis of benign prostatic hyperplasia. Am J Med. 1980 May;68(5):745-56.PubMed: 6155068
  8. 8 . Steiner JF: Clinical pharmacokinetics and pharmacodynamics of finasteride. Clin Pharmacokinet. 1996 Jan;30(1):16-27. doi: 10.2165/00003088-199630010-00002.PubMed: 8846625
  9. 9 . Carson C 3rd, Rittmaster R: The role of dihydrotestosterone in benign prostatic hyperplasia. Urology. 2003 Apr;61(4 Suppl 1):2-7.PubMed: 12657354
  10. 10 . 34. (2012). In Rang and Dale's Pharmacology (7th ed., pp. 424). Edinburgh: Elsevier/Churchill Livingstone.
  11. 11 . PROPECIA® (finasteride) tablets for oral use - FDA Label Link
  12. 12 . Finasteride - StatPearls - NCBI Bookshelf Link
  13. 13 . Proscar (finasteride) tablets label - FDA Label Link