Finasteride is the generic name for a medication used to treat benign prostatic hyperplasia and androgenetic alopecia in men. It is available as both the generic version and the branded version, thus, it is manufactured by several pharmaceutical companies. The different manufacturers may give different instructions for use. The more popular brands of Finasteride are Propecia and Proscar.
Finasteride is available as both 1mg and 5mg film-coated tablets. Lactose monohydrate is included in the formulation of both the 1mg and 5mg tablets.
Finasteride 1mg belongs to the pharmacotherapeutic group known as other dermatological whilst Finasteride 5mg belongs to the pharmacotherapeutic group known as Testosterone-5α-reductase-inhibitors. It is a specific inhibitor of the enzyme 5α-reductase that metabolises testosterone into the more potent androgen, dihydrotestosterone.
The tablets have different markers to identify them. For example, with the Finasteride tablets manufactured by Accord Healthcare LTD, the 1mg tablets are reddish brown, round, biconvex, film-coated tablets, marked ‘F1′ on one side and plain on other side whilst the 5mg tablets are blue, round biconvex, film-coated tablet with “F5″ marking on one side and plain on the other side.
Apart from the film-coated tablets, other forms are available from special-order manufacturers. These forms include oral suspensions and powders.
Finasteride 1 mg is indicated for the treatment of the first stage of the hair loss (androgenetic alopecia) in males. It stabilizes the process of the androgenetic alopecia in the 18 – 41-year-old males. Its effectiveness in a bi-temporary recession nor in the loss of hair has not been determined.
Finasteride 1mg is not indicated for use in women or children and adolescents.
The recommended dosage is one 1 mg tablet taken orally once daily. Finasteride 1mg tablets may be taken with or without food. The tablet should be swallowed whole and must not be divided or crushed.
There is no evidence that an increase in dosage will result in increased efficacy.
Efficacy and duration of treatment should constantly be assessed by the treating physician. Generally, three to six months of once-daily treatment are required before evidence of stabilization of hair loss can be expected. Continuous use is recommended to sustain benefit. If treatment is stopped, the beneficial effects begin to reverse by six months and return to baseline by 9 to 12 months.
Finasteride 5 mg Tablets are indicated for the treatment and control of benign prostatic hyperplasia (BPH) to:
– cause regression of the enlarged prostate, improve urinary flow and improve the symptoms associated with BPH,
– reduce the incidence of acute urinary retention and reduce the need for surgery including transurethral resection of the prostate (TURP) and prostatectomy.
Finasteride 5 mg tablets should be administered in patients with an enlarged prostate (prostate volume above ca. 40 ml).
Finasteride 5mg is not indicated for use in women or children and adolescents.
The recommended dose of Finasteride for the treatment of BPH is one 5 mg tablet taken orally once daily with or without food. The tablet should be swallowed whole and must not be divided or crushed. Whilst some improvement may be seen within a short time from when treatment is initiated, treatment for at least 6 months may be necessary to determine objectively whether a satisfactory response to treatment has been achieved.
Finasteride is a 4-azasteroid, which inhibits human Type 2 5α-reductase (present within the hair follicles) with a greater than 100-fold selectivity over human Type 1 5α-reductase, and blocks the peripheral conversion of testosterone to the androgen dihydrotestosterone (DHT).
In men with male pattern hair loss, the balding scalp contains miniaturized hair follicles and increased amounts of DHT. Finasteride inhibits a process responsible for miniaturization of the scalp hair follicles, which can lead to a reversal of the balding process.
Finasteride is a synthetic 4-azasteroid, a specific competitive inhibitor of the intracellular enzyme Type-II-5a-reductase. The enzyme converts testosterone into the more potent androgen dihydrotestosterone (DHT).
The prostate gland and, consequently, also the hyperplastic prostate tissue is dependent on the conversion, of testosterone to DHT for their normal function and growth. In benign prostatic hyperplasia (BPH), enlargement of the prostate gland is dependent upon the conversion of testosterone to DHT within the prostate. Finasteride is highly effective in reducing circulating and intraprostatic DHT.
Finasteride has no affinity for the androgen receptor.
The best way to prove the effectiveness of any medication is through clinical trials. To assess the effectiveness of any medications, the results of all clinical trials need to be evaluated.
Studies in men:
The efficacy of finasteride 1mg tablets was demonstrated in three studies in 1879 men 18 to 41 years of age with mild to moderate, but not complete, vertex hair loss and frontal/mid-area hair loss. In these studies, hair growth was assessed using four separate measures including hair count, ratings of photographs of the head by an expert panel of dermatologists, investigator assessment, and patient self-assessment.
In the two studies in men with vertex hair loss, treatment with Finasteride 1mg tablets was continued for 5 years, during which time patients improved compared to baseline in men treated with finasteride 1mg tablets were generally greatest at 2 years and gradually declined thereafter (e.g., hair count in a representative 5.1 cm2 area was increased 88 hairs from baseline at 2 years and 38 hairs from baseline at 5 years), hair loss in the placebo group progressively worsened compared to baseline (decrease of 50 hairs at 2 years and 239 hairs at 5 years). Thus, although improvement compared to baseline in men treated with finasteride 1mg tablets did not increase further after 2 years, the difference between treatment groups continued to increase throughout the 5 years of the studies. Treatment with finasteride 1mg tablets for 5 years resulted in stabilization of hair loss in 90% of men based on photographic assessment and in 93% based on investigator assessment.
In addition, increased hair growth was observed in 65% of men treated with finasteride 1mg tablets based on hair counts, in 48% based on photographic assessment, and in 77% based on investigator assessment. In contrast, in the placebo group, gradual hair loss over time was observed in 100% of men based on hair counts, in 75% based on photographic assessment, and in 38% based on investigator assessment. In addition, patient self-assessment demonstrated significant increases in hair density, decreases in hair loss, and improvement in the appearance of hair after treatment over 5 years with finasteride 1mg tablets (see Table below).
% of Patients Improved as Assessed by Each of the 4 Measures
Finasteride 1mg Tablets
Finasteride 1mg Tablets
Finasteride 1mg Tablets
Global Photographic Assessment
Patient Self-Assessment: Satisfaction with appearance of hair overall
† Randomization 1:1 Finasteride 1mg Tablets to placebo
† Randomization 9:1 Finasteride 1mg Tablets to placebo
In a 12-month study, in men with frontal/mid-area hair loss, hair counts were obtained in a representative 1 cm2 area (approximately 1/5 the size of the area sampled in the vertex studies). Hair counts, adjusted to a 5.1 cm2 area, increased by 49 hairs (5%) compared to baseline and by 59 hairs (6%) compared to placebo. This study also demonstrated significant improvements in patient self-assessment, investigator assessment, and ratings of photographs of the head by an expert panel of dermatologists. Two studies of 12 and 24 weeks duration showed that a dose 5-fold the recommended dose (finasteride 5 mg daily) produced a median decrease in ejaculate volume of approximately 0.5 mL (-25%) compared with placebo. This decrease was reversible after discontinuation of treatment. In a study of 48 weeks of duration, Finasteride 1 mg daily produced a median decrease in ejaculate volume of 0.3 mL (-11%) compared with a 0.2 mL (-8%) decrease for placebo. No effect was observed on sperm count, motility or morphology. Longer-term data are not available. It has not been feasible to undertake clinical studies, which directly elucidate possible negative effects on fertility. However, such effects are judged as very unlikely (see also 5.3 Preclinical safety data).
Studies in women
Lack of efficacy was demonstrated in post-menopausal women with androgenetic alopecia who were treated with finasteride 1 mg tablets in a 12-month, placebo-controlled study (n=137). These women did not show any improvement in hair count, patient self-assessment, investigator assessment, or ratings based on standardized photographs, compared with the placebo group.
Relative to an intravenous reference dose, the oral bioavailability of finasteride is approximately 80%. The bioavailability is not affected by food. Maximum finasteride plasma concentrations are reached approximately two hours after dosing and the absorption is complete after six to eight hours.
Clinical studies have shown a rapid reduction of the Serum DHT levels of 70%, which leads to a reduction in prostate volume. After 3 months, a reduction of approx. 20% in the volume of the gland occurs, and the shrinking continues and reaches approx. 27% after 3 years. Marked reduction takes place in the periurethral Zone immediately surrounding the Urethra.
Urodynamic measurements have also confirmed a significant reduction of detrusor pressure because of the reduced obstruction.
Significant improvements in the maximum urinary flow rate and symptoms have been obtained after a few weeks, compared with the stand of treatment. Differences from placebo have been documented at 4 and 7 months, respectively.
All efficacy parameters have been maintained over a 3-year follow-up period.
Effects of four years of treatment with finasteride on the incidence of acute urine retention need for surgery, symptom-Score and prostate volume:
In clinical studies of patients with moderate to severe symptoms of BPH, an enlarged prostate on digital rectal examination and low residual urinary volumes, finasteride reduced the incidence of acute retention of urine from 7/1 00 to 3/100 over four years and the need for surgery (TURP or prostatectomy) from 10/100 to 5/100. These reductions were associated with a 2-point improvement in QUASJ-AUA Symptom Score (range 0-34), a sustained regression in the prostate volume of approximately 20% and a sustained increase in urinary flow rate.
Medical therapy of prostatic symptoms
The Medical Therapy of Prostatic Symptoms (MTOPS) Trial was a 4-to-6 year study in 3047 men with symptomatic BPH who were randomised to receive finasteride 5 mg/day, doxazosin 4 or 8 mg/day*, the combination of finasteride 5 mg/day and doxazosin 4 or 8 mg/day*, or placebo. The primary endpoint was time to clinical progression of BPH, defined as a ≥ 4 point confirmed increase from baseline in symptom score, acute urinary retention, BPH-related renal insufficiency, recurrent urinary tract infections or urosepsis, or incontinence. Compared to placebo, treatment with finasteride, doxazosin, or combination therapy resulted in a significant reduction in the risk of clinical progression of BPH by 34 (p=0.002), 39 (p<0.001), and 67% (p<0.001), respectively.
The majority of the events (274 out of 351) that constituted BPH progression were confirmed ≥ 4 point increases in symptom score; the risk of symptom score progression was reduced by 30 (95% CI 6 to 48%), 46 (95% CI 25 to 60%), and 64% (95% CI 48 to 75%) in the finasteride, doxazosin, and combination groups, respectively, compared to placebo. Acute urinary retention accounted for 41 of the 351 events of BPH progression; the risk of developing acute urinary retention was reduced by 67 (p=0.011), 31 (p=0.296), and 79% (p=0.001) in the finasteride, doxazosin, and combination groups, respectively, compared to placebo. Only the finasteride and combination therapy groups were significantly different from placebo.
^Titrated from 1 mg to 4 or 8 mg as tolerated over a 3-week period
In this stud,y the safety and tolerability profile of combined treatment was broadly similar to the profile of each of the drugs taken separately. However, undesirable effects concerning the “nervous system” and urogenital system” organ classes were observed more frequently when the two drugs were used in combination
The oral bioavailability of finasteride is approx. 80%. Peak plasma concentrations are reached approx. 2 hours after the dose was taken orally, and absorption is complete after 6-8 hours.
Finasteride is metabolised in the liver. Finasteride does not significantly affect the cytochrome P 450 enzyme system. Two metabolites with low 5α-reductase-inhibiting effects have been identified. Elimination:
The plasma half-life averages 6 hours (4-12 hours) (in men >70 years of age, 8 hours, range 6-15 hours). After administration of radioactively labelled finasteride, approx. 39% (32-46%) of the given dose is excreted in the urine in the form of metabolites. Virtually no unchanged finasteride is recovered in the urine. Approximately 57% (51-64%) of the total dose is excreted in the faeces.
Finasteride has been found to cross the blood-brain barrier. Small amounts of finasteride have been recovered in the seminal fluid of those treated. In 2 studies of healthy subjects (n=69) receiving finasteride 5 mg/day for 6-24 weeks, finasteride concentrations in semen ranged from undetectable (<0.1 ng/ml) to 10.54 ng/ml. In an earlier study using a less sensitive assay, finasteride concentrations in the semen of 16 subjects receiving finasteride 5 mg/day ranged from undetectable (<1.0 ng/ml) to 21 ng/ml. Thus, based on a 5-ml ejaculate volume, the amount of finasteride in semen was estimated to be 50- to 100-fold less than the dose of finasteride (5 μg) that had no effect on circulating DHT levels in men (see also section 5.3.).
In patients with chronic renal impairment, whose creatinine clearance ranged from 9-55 ml/min, the disposition of a single dose of 14C-finasteride was not different from that in healthy volunteers (see section 4.2). Protein binding also did not differ in patients with renal impairment. A portion of the metabolites, which normally is excreted renally, was excreted in the faeces. It therefore appears that faecal excretion increases commensurate to the decrease in urinary excretion of metabolites. Dosage adjustment in non-dialysed patients with renal impairment is not necessary.
Important safety information
MHRA/CHM advice: rare reports of depression and suicidal thoughts (May 2017)
The MHRA (Medicines and Healthcare products Regulatory Agency) has received reports of depression and, in rare cases, suicidal thoughts in men taking finasteride (Propecia®) for male pattern hair loss; depression is also associated with Proscar® for benign prostatic hyperplasia. Thus, patients are advised to stop taking Finasteride tablets immediately and inform a healthcare professional if they develop depression and/or have suicidal thoughts.
Conception and contraception
Finasteride is excreted in the semen and the use of a condom is recommended if the man’s sexual partner is pregnant or likely to become pregnant.
Handling and storage
Women of childbearing potential ie women who are pregnant or can get pregnant, are advised to avoid handling crushed or broken tablets of Finasteride. This is because of the possibility of absorption of Finasteride and the subsequent potential risk to a male foetus
Patient and carer advice
Cases of male breast cancer have been reported in patients taking Finasteride tablets. Thus, patients and/or their carers are advised to promptly report to their doctor if they notice any changes in breast tissue such as lumps, pain, or nipple discharge.
How to report suspected adverse reactions
It is essential that even after the marketing authority has been granted to a medicine that it is continually monitored for adverse reactions. It allows for continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals and members of the public are encouraged to report any suspected adverse reactions via the Yellow Card Scheme.
If you would like to find out more about the Yellow Card Scheme, you can do so on the Medicines and Healthcare products Regulatory Agency (MHRA) website.
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