Drug Interaction:
May increase clearance of theophylline. Half-life of aminophylline may be reduced
Indication:
Benign prostatic hyperplasia
to reduce incidence of urinary retention and need for surgery
Approved by FDA on June 19,1992.
Approved by (DCI) Drug Controller GENERAL - India For Marketing
(Ref- IDMA Publication)
Name of Drug Indication Date of Approval
Finasteride Benign prostatic 09-10-1996
hypertrophy
Adverse Reaction:
Gynaecomastia, decreased libido, impotence, reduction in the volume of ejaculate, general abnormalities in the male fetus of pregnant women exposed to Finasteride.
Hypersensitivity reactions such as swelling of lips & rashes.
Contra-Indications:
Hypersensitivity,pregnancy & lactation,children.
Special Precautions
Exposure of pregnant women to Finasteride,either via direct contact with crushed tablets or through semen of male sexual partners who are in the drug,should be avoided.
Undiagnosied prostrate cancer(the drug may mask the serum makers),liver diseases.
Dosages/ Overdosage Etc:
Approved by FDA on June 19,1992.
Indication-
Benign prostatic hyperplasia to reduce incidence of urinary retention and need for surgery
Dosage-
The recommended dosage is 5mg once a day,with or without meals, for a minimum period of 6 months
Other Information:
EVIDENCE BASED MEDICINE
Management of Benign Prostatic Hypertrophy (BPH)
Comparative effectiveness of various interventions
Beneficial
1. Aplha blockers (parzosin, alfuzosin, indoramin, terazosin, doxazosin,tamsulosin)
2. 5-alpha -reductase inhibitors (e.g. finastreride)
3. Transureythral resection (TURP)
4. Transurethral microwave thermotherapy (TUMT)
5. Trnasurethral needle ablation (TUNA)
Unknown effectiveness
1. TURP versus less invasive techniques
KEY POINTS
1. Randomised controlled trials (RCTs) have found that both alpha-blockers and 5-alpha-reductase-inhibitors are more effective than placebo in improving lower urinary tract symptoms in men with BPH.
2. One trial found that alpha-blockers (e.g.prazosin ) were more effective than 5-alpha- reductase inhibitors (finasteride) in men not selected for having large prostrates.
3. Neither drug has been compared directly with surgical treatment
4. There is limited evidence from one trial that TURP is more effective than watchful waiting in improving symptoms and reducing complications, and does not increase the risk of ercetile dysfunction or incontinuence.
5. TURP has not yet been adequately compared with medical treatments or with newer less invasive techniques.
6. TUMT is more effective than sham treatment at reducing symptoms. There is no difference beween TURP and TUMT with regard to short term relief
7. One trial found that TURP was more effective than TUNA in men with BPH.
Patient Information:
1.Crushed Finasteride should not be handled by woman who is pregnant or who may become pregnant because of potential for absorption of Finasteride and the subsequent potential risk to the male fetus.
Similarly,when the male patients sexual partner is or may become pregnant, the patient should either avoid exposure of his partner to semen or he should discontinue Finasteride.
2. Inform patient that the volume of ejaculate may be decreased in some patients during
treatment..This decrease does not appear to interfere with normal sexual function. However, impotence and decreased libido may occur.
3. Allergies- Tell your doctor if you have ever had any unusual or allergic reactions to ffinasteride.
Also tell your doctor if your are allergic to any other substances such as foods,
preservatives or dyes.
4. Pregnancy- discuss with your doctor the need to stop taking finasteride if your partner wishes to become pregnant.
5. Elderly- this medicine has not shown to cause different side effects or problems in older people than it does in younger adults
6. Other medicines- tell your doctor if you are taking any other medicines-
Amantadine or Amphetamines or Anticholinergic or Antidepressants or Antidyskinetcis or Antihistamines or Antipsychotics or Appetite stimulants or these medicines could reduce the effects of finasteride
11. Other medical problems- presence of other medical problems may affect the use of the medicine Liver disease- effects of finasteride may be increased because of slower removal from the body.
12. Missed dose-
If you miss a dose of this medicine take it as soon as possible. However if it is almost time for your next dose go back to your regular dosing schedule.
Do not double doses.
Pharmacology/ Pharmacokinetics:
Ref- Drug Facts And comparisons(2010)
Pharmacology:
Finasteride,a synthetic 4-azosteroid compound,is a competitive and specific inhibitor or steroid 5alpha reductace,an intercellular enzyme that converts testosterone into potential androgen 5alpha-dihydrotestosterone(DHT).
Pharmacokinetics:
Following an oral dose,a mean of 39% was excreted in the urine in the form of metabolites,and 57% was excreted in feces.
Pharmacokinetics Parameters in Healthy Young Subjects (n=15)
Parameter Mean (+/- SD)
Bioavailability 63%
(34% to 108%)
Clearance (ml/min) 165 (55)
Volume of distribution (L) 76(14)
Half-life (hours) 6.2 (2.1)
Noncompartmental Pharmacokinetics Parameters After Multiple doses of
5mg/day in Older men
Parameter Mean(+/- SD)
45 to 60 years of age >70 years of age
(n=12) (n=12)
AUC (ng*hr/mL) 389 (98) 463(86)
Peak concentration 46.2 (68.7) 48.4( 14.7)
(ng/mL)
Time to peak(hours) 1.8(0.7) 1.8(0.5)
half life (hours) 6 (1.5) 8.2(2.5)
Pregnancy and lactation:
Pregnancy: Finasteride is not indicated for use in women. Exposure of pregnant women to Finasteride,either via direct contact with crushed tablets or through semen of male sexual partners who are in the drug,should be avoided. Lactation: Not indicated for use in women. Children: Safety and efficacy for use in children have not been established.
Manufacturer Details