Finasteride
[CAS# 98319-26-7]

Identification

• Classification: API >> Urinary system medication >> Other urinary system medication
• Name: Finasteride
• Synonyms: N-(2-methyl-2-propyl)-3-oxo-4-aza-5alpha-androst-1-ene-17beta-carboxamide; Proscar
• Molecular Formula: C₂₃H₃₆N₂O₂
• Molecular Weight: 372.55
• CAS Registry Number: 98319-26-7
• EC Number: 620-534-3
• SMILES: C[C@]12CC[C@H]3[C@H]([C@@H]1CC[C@@H]2C(=O)NC(C)(C)C)CC[C@@H]4[C@@]3(C=CC(=O)N4)C

Properties

• Water solubility: insoluble

Safety Data

• Hazard Symbols: GHS07;GHS08;GHS09 Danger
• Risk Statements: H302-H360-H360D-H372-H410
• Safety Statements: P203-P260-P264-P270-P273-P280-P301+P317-P318-P319-P330-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Specific target organ toxicity - repeated exposure	STOT RE	1	H372
Reproductive toxicity	Repr.	1B	H360
Reproductive toxicity	Repr.	1B	H360D
Reproductive toxicity	Repr.	2	H361
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	1	H302
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H312
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Finasteride is a synthetic 4-azasteroid compound that has significantly impacted the treatment of benign prostatic hyperplasia (BPH) and androgenetic alopecia (male pattern baldness). Developed in the late 1980s by the pharmaceutical company Merck, Finasteride was approved by the FDA in 1992 for BPH treatment and later in 1997 for treating hair loss in men.

The discovery of Finasteride originated from research into the role of androgens in prostate growth and hair loss. Scientists identified dihydrotestosterone (DHT), a potent androgen derived from testosterone by the action of the enzyme 5-alpha-reductase, as a critical factor in both conditions. DHT is essential for the development of male characteristics but its excessive production can lead to prostate enlargement and hair follicle miniaturization.

Finasteride works by inhibiting type II 5-alpha-reductase, the enzyme responsible for converting testosterone to DHT. By reducing DHT levels, Finasteride helps to shrink the enlarged prostate in BPH patients, alleviating urinary symptoms such as difficulty in starting urination, weak stream, and frequent urination. Clinical studies have shown that Finasteride significantly reduces the need for surgery in BPH patients and improves their quality of life.

In the context of androgenetic alopecia, Finasteride's inhibition of DHT helps to halt hair loss and stimulate hair regrowth. Hair follicles affected by DHT tend to shrink, leading to thinning hair and eventual hair loss. By lowering DHT levels, Finasteride allows hair follicles to recover, increasing hair count and improving hair density. It is one of the few medications that have been scientifically proven to be effective in treating male pattern baldness.

Apart from its primary uses, Finasteride has been studied for other potential applications. Research is ongoing into its effects on prostate cancer prevention, as DHT plays a role in prostate cancer development. Some studies suggest that Finasteride may reduce the incidence of low-grade prostate cancers, although its impact on high-grade cancer is still debated.

Finasteride's effectiveness and relatively mild side effect profile have made it a widely used treatment. However, potential side effects include sexual dysfunction, such as decreased libido and erectile dysfunction, which can persist even after discontinuation of the drug in some cases. Due to these concerns, it is crucial for patients to discuss the risks and benefits of Finasteride with their healthcare provider.

Overall, Finasteride represents a significant advancement in the treatment of BPH and androgenetic alopecia. Its ability to inhibit the production of DHT addresses the underlying cause of these conditions, providing relief and improving quality of life for many patients. The continued study and application of Finasteride highlight its importance in clinical medicine and potential for broader therapeutic uses.

References

1994. Effect of Finasteride on Adrenal Steroidogenesis in Men. Journal of Andrology, 15(4).
DOI: 10.1002/j.1939-4640.1994.tb00453.x

1998. A Risk-Benefit Assessment of Treatment with Finasteride in Benign Prostatic Hyperplasia. Drug Safety, 18(3).
DOI: 10.2165/00002018-199818030-00002

2003. Doxazosin and finasteride alone or in combination: the PREDICT study. BJU International, 91(7).
DOI: 10.1046/j.1464-410x.2003.04214.x