Finasteride: Dosage, Uses & side effects for hair Loss
What is Finasteride?
Finasteride is a 5-alpha reductase inhibitor, mostly used in the management of male pattern hair loss and stimulation of re-growth of hair in men. It is also indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate. Finasteride is commonly sold under brand names as “Proscar” (for benign prostatic hyperplasia) and “Propecia” (for male pattern hair loss).
Why Finasteride should be used?
- Hair loss occurs when testosterone gets converted into DHT and binds to an androgen receptor which led to hair fall.
- So, to reduce hair fall, a DHT blocker like finasteride is necessary which will stop this conversion and can prevent hair fall.
How DHT causes hair fall?
- Hair growth mainly starts from the cells present at the base of hair shaft known as dermal papilla.
- These cells divide and proliferate to form new hair follicles.
- Dermal papilla cells carry all the essential nutrients required for the hair growth along with androgen (hormone).
- When hair follicles exposed to DHT, hair growth retards and disrupted resulting in hair miniaturization and hair loss.
How Finasteride works and helps to reduce hair fall?
- Finasteride is a specific inhibitor of type II 5 alpha reductase, an enzyme responsible for the conversion of testosterone to DHT.
- It regulates the production of dihydrotestosterone.
- Finasteride acts on the binding site of DHT and stops the transmission of DHT to further hair follicles.
- DHT causes the shrinkage of hair follicles and shortens the growing phase.
- By lowering the DHT levels, finasteride reverses the harmful effects on hair follicles and stimulates re-growth of hair.
- Finasteride can decrease DHT concentrations in the serum and scalp up to 60-70% approximately.
How finasteride is different from natural DHT blockers?
- Finasteride is approved by FDA for the treatment of hair loss.
- Studies have shown that finasteride decreases serum DHT levels approximately by 71% while natural DHT blockers like saw palmetto decreases such by approximately 32%.
- Finasteride can act both on the front area and on the vertex to reduce hair fall while saw palmetto prevalently in vertex.
Finasteride for female pattern hair loss
It is believed that women with hyperandrogenism might be more likely to benefit from finasteride treatment. Finasteride 1.25 mg or 2.5 mg daily, effectively promotes scalp hair growth.
Finasteride is indicated for androgenetic alopecia in males. It stabilizes the male pattern hair loss in the males aged from 18-41 year old.
It is classified in the FDA pregnancy category. Women should not even touch this medicine in pregnancy
- Use in children or adolescents
- Use in pregnancy
There are no significant any drug interactions with clinically important which have been demonstrated with finasteride.
Active ingredient: Finasteride.Inactive ingredients include:
- Lactose monohydrate
- Microcrystalline cellulose
- Pregelatinized starch
- Sodium starch glycolate
- Hydroxypropyl methylcellulose
- Hydroxypropyl cellulose
- Titanium dioxide
- Magnesium stearate, talc
- Docusate sodium
- Yellow ferric oxide and red ferric oxide
Mostly used Brands of Finasteride and price
|PROPECIA||Merck||Finasteride (1mg)||Rs. 955.13/ 28 Tabs|
|FINAST||Dr Reddy's Laboratories Ltd||Finasteride (5mg)||Rs. 528/ 30 Tabs|
|FINAST||Dr Reddy's Laboratories Ltd||Finasteride (1mg)||Rs. 178/ 30 Tabs|
|FINPECIA||Cipla Ltd||Finasteride (1mg)||Rs. 91/ 15 Tabs|
|FINCAR||Cipla Ltd||Finasteride (5mg)||Rs. 147/ 10 Tabs|
Medical uses of Finasteride
Finasteride is used to treat
- Male pattern hair loss
- Overall risk of prostate cancer
- Alone or in combination with other drug to treat benign prostatic hypertrophy
- Acute urinary retention
Off label uses include
- Hirsutism (excessive facial and/or body hair growth)
- Hormone Replacement therapy
Oral Finasteride has been known to associate with side effects such as erectile dysfunction, low libido due to decreased levels of DHT in blood. A topical formulation of finasteride has been formulated along with minoxidil. Minoxidil helps finasteride in better absorption due to its vasodilator property. A clinical trial has shown that 1mg of topical finasteride controls more DHT levels in scalp than oral finasteride. Meanwhile, both topical and oral administrations decrease almost similar DHT level in serum. But study also suggests that if you get a side effect from oral finasteride, most likely you will get a side effect from topical finasteride also.
|Finasteride Form||DHT level change in the
scalp (decreased by)
|DHT level change in
serum (decreased by)
Adverse effects of Finasteride
- Post finasteride syndrome (PFS) usually occurs in patients taking finasteride. This symptom complex can be physical, sexual, as well as neurological. It is also known as 5 alpha reductase inhibitor syndrome. Few men may also complain of side effect such as ‘brain fog’ or cognitive impairment. This is the most discussed concept and still no clinical data is published.
- Studies have shown that finasteride may be involved in altering the immune system of the body against carcinoma cells or cancer in aging men.
- As finasteride inhibits the DHT, ratio of estrogen to androgen alters which can increase the risk of gynecomastia and male breast cancer.
Finasteride is a synthetically derived 4-azasteroid reductase. It is a specific inhibitor of steroid type II DHT, testosterone to 5 carboxamide. Its structural formula is;
- Generic name of finasteride for the treatment of hair loss is Propecia which was originally developed and manufactured by Merck Pharmaceuticals.
- P. Roy Vagelos (Merck’s basic research chief) in 1975 was intrigued by the perception of decreased levels of DHT (Dihydrotestosterone) which led to the development of smaller prostates and increased hair growth. Dr. Vagelos then created a drug which could treat or mimic the condition.
- Finasteride (1mg) was approved by FDA in 1997 under the brand name Propecia which was marketed by Merck.
Finasteride is a white crystalline powder and freely soluble in chloroform, alcoholic solvents but is insoluble in water. Many scientific research or clinical studies have been conducted on Finasteride and various physical or chemical data have been collected which is as follows:
|Clinical data||Legal status||Pharmacokinetic data||Chemical & physical data|
|Trade names - Propecia, Proscar||UK: POM (Prescription only)||Bioavailability - 63%||Formula C23H36N2O2|
|Pregnancy category - X (will cause birth defects)||US: ?-only||Metabolism - Liver||Molar mass 372.549 g/mol|
|Routes of administration - By mouth||Biological
half-life- Adults: 6 hours
Elderly: 8 hours
|ATC code - G04CB01 D11AX10||Excretion - Feces (57%) and urine (39%) as metabolites||Rs. 91/ 15 Tabs|
|FINCAR||Cipla Ltd||Finasteride (5mg)||Rs. 147/ 10 Tabs|
|ATC= Anatomical Therapeutic Chemical Classification system|
Frequently Asked Questions about FinasterideIs Finasteride a steroid?
- The most common side effects of Finasteride are:
- Erectile dysfunction
- Loss of libido
- Low Blood pressure or hypertension
- Depression, drowsiness
- Difficulty in breathing
- Fatigue, weakness, headache
- Men are at risk of developing obstructive uropathy. So consult with your doctor before taking.
- Do not use finasteride if you are allergic to finasteride or any other inactive ingredient present in finasteride tablet.
- Finasteride can be absorbed through the skin. Women who are pregnant should avoid contact with crushed or broken tablets.
- Avoid contact with semen from a male partner who is exposed to finasteride as it can retard fetal growth.
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