Urifix F

Urifix F Uses, Dosage, Side Effects, Food Interaction and all others data.

Finasteride, a competitive inhibitor of the 5α reductase enzyme which is used in the treatment of benign prostatic hyperplasia. It is selective for 5α reductase type 2 enzyme and has no affinity for androgen receptors. The development of the prostate gland and subsequent BPH is dependent upon conversion of testosterone to dihydrotestosterone (DHT) within the prostate. Finasteride belongs to a new class of specific inhibitors of 5α reductase, an intracellular enzyme, which metabolises testosterone into the more potent androgen, DHT. Finasteride has no affinity for the androgen receptor.

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 observed 8 hours following administration of the first dose. In a single man receiving a single oral dose of 5 mg finasteride for up to 4 years, there was a reduction in the serum DHT concentrations by approximately 70% and the median circulating level of testosterone increased by approximately 10-20% within the physiologic range. In a double-blind, placebo-controlled study, finasteride reduced intraprostatic DHT level by 91.4% but finasteride is not expected to decrease the DHT levels to castrate levels since circulating testosterone is also converted to DHT by the type 1 isoenzyme expressed in other tissues. It is expected that DHT levels return to normal within 14 days upon discontinuation of the drug. In a study of male patients with benign prostatic hyperplasia prior to prostatectomy, the treatment with finasteride resulted in an approximate 80% lower DHT content was measured in prostatic tissue removed at surgery compared to placebo. While finasteride reduces the size of the prostate gland by 20%, this may not correlate well with improvement in symptoms. The effects of finasteride are reported to be more pronounced in male patients with enlarged prostates (>25 mL) who are at the greatest risk of disease progression.

In phase III clinical studies, oral administration of finasteride in male patients with male pattern hair loss promoted hair growth and prevented further hair loss by 66% and 83% of the subjects, respectively, which lasted during two years' treatment. The incidences of these effects in treatment groups were significantly higher than that of the group receiving a placebo. Following finasteride administration, the levels of DHT in the scalp skin was shown to be reduced by more than 60%, indicating that the DHT found in scalp is derived from both local DHT production and circulating DHT. The effect of finasteride on scalp DHT is likely seen because of its effect on both local follicular DHT levels as well as serum DHT levels.. There is evidence from early clinical observations and controlled studies that finasteride may reduce bleeding of prostatic origin.

Tamsulosin is an antagonist of α1A-adrenoreceptors in the prostate. It binds selectively and competitively to postsynaptic α1A-adrenoreceptors, which convey smooth muscle contraction, thereby relaxing prostatic and urethral smooth muscle.

Tamsulosin is an alpha adrenoceptor blocker with specificity for the alpha-1A and alpha-1D subtypes, which are more common in the prostate and submaxillary tissue. The final subtype, alpha-1B, are most common in the aorta and spleen. Tamsulosin binds to alpha-1A receptors 3.9-38 times more selectively than alpha-1B and 3-20 times more selectively than alpha-1D. This selectivity allows for a significant effect on urinary flow with a reduced incidence of adverse reactions like orthostatic hypotension.

Urifix F
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Urifix F
Generic	Tamsulosin + Finasteride
Weight	0.4mg
Type	Tablet
Therapeutic Class
Manufacturer	Nitro Cadineur
Available Country	India
Last Updated:	September 19, 2023 at 7:00 am

Uses

Finasteride is used for the treatment and control of benign prostatic hyperplasia (BPH)-

To cause regression of the enlarged prostate
To improve urinary flow
To improve the symptoms associated with BPH.

Tamsulosin Hydrochloride is used for the treatment of the signs and symptoms of Benign Prostatic Hyperplasia (BPH).

Urifix F is also used to associated treatment for these conditions: Androgenetic Alopecia, Benign Prostatic Hyperplasia (BPH), Idiopathic Hirsutism, Symptomatic Benign Prostatic HyperplasiaBenign Prostatic Hyperplasia (BPH), Benign Prostatic Hypertrophy, Bladder Outlet Obstruction, Ureteral Calculus

How Urifix F works

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). DHT is considered to be the primary androgen playing a role in the development and enlargement of the prostate gland. It serves as the hormonal mediator for the hyperplasia upon accumulation within the prostate gland. DHT displays a higher affinity towards androgen receptors in the prostate gland compared to testosterone and by acting on the androgen receptors, DHT modulates genes that are responsible for cell proliferation. Responsible for the production of DHT together with type I 5α-reductase, the type II 5α-reductase isozyme is primarily found in the prostate, seminal vesicles, epididymides, and hair follicles as well as liver. Although finasteride is 100-fold more selective for type II 5α-reductase than for the type I isoenzyme, chronic treatment with this drug may have some effect on type I 5α-reductase, which is predominantly expressed in sebaceous glands of most regions of skin, including the scalp, and liver. It is proposed that the type I 5α-reductase and type II 5α-reductase is responsible for the production of one-third and two-thirds of circulating DHT, respectively.

The mechanism of action of Finasteride is based on its preferential inhibition of Type II 5α-reductase through the formation of a stable complex with the enzyme in vitro and in vivo. Finasteride works selectively, where it preferentially displays a 100-fold selectivity for the human Type II 5α-reductase over type I enzyme. Inhibition of Type II 5α-reductase blocks the peripheral conversion of testosterone to DHT, resulting in significant decreases in serum and tissue DHT concentrations, minimal to moderate increase in serum testosterone concentrations, and substantial increases in prostatic testosterone concentrations. As DHT appears to be the principal androgen responsible for stimulation of prostatic growth, a decrease in DHT concentrations will result in a decrease in prostatic volume (approximately 20-30% after 6-24 months of continued therapy). It is suggested that increased levels of DHT can lead to potentiated transcription of prostaglandin D2, which promotes the proliferation of prostate cancer cells. In men with androgenic alopecia, the mechanism of action has not been fully determined, but finasteride has shown to decrease scalp DHT concentration to the levels found in the hairy scalp, reduce serum DHT, increase hair regrowth, and slow hair loss. Another study suggests that finasteride may work to reduce bleeding of prostatic origin by inhibiting vascular endothelial growth factor (VEGF) in the prostate, leading to atrophy and programmed cell death. This may bestow the drug therapeutic benefits in patients idiopathic prostatic bleeding, bleeding during anticoagulation, or bleeding after instrumentation.

Tamsulosin is a blocker of alpha-1A and alpha-1D adrenoceptors. About 70% of the alpha-1 adrenoceptors in the prostate are of the alpha-1A subtype. By blocking these adrenoceptors, smooth muscle in the prostate is relaxed and urinary flow is improved. The blocking of alpha-1D adrenoceptors relaxes the detrusor muscles of the bladder which prevents storage symptoms. The specificity of tamsulosin focuses the effects to the target area while minimizing effects in other areas.

Dosage

Urifix F dosage

The recommended dosage is one 5 mg tablet daily. Although early improvement may be seen, treatment for at least six months may be necessary to assess whether a beneficial response has been achieved. Thereafter, treatment should be continued.

The recommended dose of Tamsulosinis 0.4 mg once daily. It should be administered approximately half/hour following the same meal each day. For those patients who fail to respond to the 0.4 mg dose after two to four weeks of dosing, the dose of Tamsulosin can be increased to 0.8mg once daily. If Tamsulosin administration is discontinued or interrupted for several days at either the 0.4 mg or 0.8 mg dose, therapy should be started again with the 0.4 mg once daily dose.

Side Effects

Finasteride is well tolerated. In clinical studies, the following adverse experiences have been reported as possibly drug related in 1% of patients treated for 12 months with 5 mg Finasteride daily: impotence (3.7%), decreased libido (3.3%), and decreased volume of ejaculate (2.8%).

The following adverse reactions have been reported during the use of Tamsulosin: dizziness, abnormal ejaculation, and less frequently (1-2%) headache, asthenia, postural hypotension, palpitations, and rhinitis.

Gastrointestinal reactions such as nausea, vomiting, diarrhoea, and constipation can occasionally occur. Hypersensitivity reactions such as rash, pruritus, and urticaria can occur occasionally. As with other alpha-blockers, drowsiness, blurred vision, dry mouth, or edema can occur. Syncope has been reported rarely, and there have been very rare reports of angioedema and priapism.

Toxicity

LD50

Oral LD50 is about 418 mg/kg in rats 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.

Nonclinical toxicology

In a 24-month rat study, there were no signs of the tumorigenic potential of finasteride. In a 19-month carcinogenicity study in CD-1 mice, high doses of finasteride, at 1824 times the human exposure (250 mg/kg/day), resulted in an increase in the incidence of testicular Leydig cell adenomas and an increase in serum LH levels. In vitro mutagenesis assays demonstrated no evidence of mutagenicity. In an in vitro chromosome aberration assay, using Chinese hamster ovary cells, there was a slight increase in chromosome aberrations with much higher doses of finasteride.

Overdose

There were no reported significant adverse events in clinical trials of male patients receiving single oral doses of finasteride up to 400 mg and multiple doses of finasteride up to 80 mg/day for three months. As there have been no cases of overdose or clinically significant toxicity with finasteride, there are no specific recommendations in case of an overdose.

Significant adverse events

Common reproductive adverse events seen with finasteride therapy include erectile dysfunction, ejaculatory dysfunction, and loss of libido. These adverse events tend to disappear after discontinuation or chronic use of the drug. Only causal adverse event occurring at the male reproductive system that is caused by finasteride is decreased ejaculatory volume because of the predominant action of DHT on the prostate.

Special populations

Finasteride can be safely used in elderly patients or those with renal impairment with no specific dosing adjustment recommendations. Finasteride is indicated for male patients only, and it is advised that exposure to finasteride is avoided in pregnant women carrying male fetuses as it may lead to abnormal development of external genitalia in male fetuses.

In the event of overdose, patients may experience hypotension and should lie down in a supine position to maintain blood pressure and heart rate. If further measures are required intravenous fluids should be considered. If further progression is required, vasopressors may be used and renal function should be monitored. Dialysis is unlikely to assist in treating overdose because tamsulosin is extensively protein bound.

The oral LD50 in rats is 650mg/kg.

Tamsulosin is not indicated for use in women and no studies have been performed in pregnancy, though animal studies have not shown fetal harm. Tamsulosin is excreted in the milk of rats but there is no available data on what the effect of this tamsulosin exposure may be. Animal studies have shown male and female rat fertility is affected by tamsulosin due to impairment of ejaculation and fertilization. In men, tamsulosin is associated with abnormal ejaculation. Tamsulosin is not mutagenic but may be carcinogenic at levels above the maximum recommended human dose. Female rats experience a slight increase in the rates of mammary gland fibroadenomas and adenocarcinomas.

Precaution

General: Since the beneficial response to Finasteride may not be manifested immediately, patients with large residual urine volume and/or severely diminished urinary flow should be carefully monitored for obstructive uropathy.

Prostate cancer: Digital rectal examination, as well as, other evaluations for prostate cancer, should be performed on patients with BPH prior to initiating therapy with Finasteride and periodically thereafter. Finasteride causes a decrease in serum concentration of markers of prostatic cancer such as prostate specific antigen (PSA); therefore, reduction of serum levels of these markers in patients with BPH treated with Finasteride does not rule out concomitant prostate cancer. No clinical benefit has yet been demonstrated in patients with prostate cancer treated with Finasteride.

Not indicated for use in women. Severe renal impairment (CrCl <10 mL/min). Pregnancy and lactation.

Interaction

No clinically important drug interactions have been identified. Finasteride does not appear to significantly affect the cytochrome P450 linked drug metabolising enzyme system. Compounds which have been tested in man include Propranolol, Digoxin, Glibenclamide, Warfarin, Theophylline, and antipyrine.

Increased plasma concentration with strong CYP3A4 inhibitors (e.g. ketoconazole). Moderate CYP3A4 inhibitors (e.g. erythromycin), strong (e.g. paroxetine) or moderate (e.g. terbinafine) CYP2D6 inhibitors may increase exposure of tamsulosin. Increased plasma concentration with cimetidine. Additive effect with other α-adrenergic blocking agents. Concomitant use with PDE5 inhibitors may lead to symptomatic hypotension. Decreased plasma concentration with furosemide.

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. It is not known whether finasteride is excreted in human milk.

16L after intravenous administration.

Elimination Route

Finasteride is well absorbed following oral administration and displays a slow accumulation phase after multiple dosing.[lablel] In healthy male subjects receiving oral finasteride, the mean oral bioavailability was 65% for 1 mg finasteride and 63% for 5 mg finasteride, and the values ranged from 26 to 170% for 1 mg dose and from 34 to 108% for 5 mg dose, respectively. It is reported that food intake does not affect the oral bioavailability of the drug. The peak plasma concentrations (Cmax) averaged 37 ng/mL (range, 27-49 ng/mL) and was reached 1-2 hours post administration. The AUC(0-24 hr) was 53 ngxhr/mL (range, 20-154 ngxhr/mL). The plasma concentrations and AUC are reported to be higher in elderly male patients aged 70 years or older.

Oral tamsulosin is 90% absorbed in fasted patients. The area under the curve is 151-199ng/mL*hr for a 0.4mg oral dose and 440-557ng/mL*hr for a 0.8mg oral dose. The maximum plasma concentration is 3.1-5.3ng/mL for a 0.4mg oral dose and 2.5-3.6ng/mL for a 0.8mg oral dose. Taking tamsulosin with food increases the time to maximum concentration from 4-5 hours to 6-7 hours but increases bioavailability by 30% and maximum plasma concentration by 40-70%.

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.

The half life in fasted patients is 14.9±3.9 hours. The elimination half life is 5-7 hours and the apparent half life is 9 to 13 hours in healthy subjects. In patients who require tamsulosin, the apparent half life is 14-15 hours.

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.

2.88L/h.

Elimination Route

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 fecal excretion is increased.

97% of an orally administered does is recovered in studies, which 76% in the urine and 21% in the feces after 168 hours. 8.7% of the dose is excreted as unmetabolized tamsulosin.

Pregnancy & Breastfeeding use

Finasteride is contra-indicated in women who are or may become pregnant. Finasteride is not indicated for use in women. It is not known whether finasteride is excreted in human milk.

Exposure to finasteride- risk to male fetus: Crushed or broken Finasteride Tablets should not be handled by women who are or may become pregnant because of the possibility of absorption of finasteride and the subsequent potential risk to a male fetus. Similarly, small amounts of finasteride have been recovered from the semen in subjects receiving Finasteride 5 mg/day. It is not known whether a male fetus may be adversely affected if his mother is exposed to the semen of a patient being treated with finasteride. Therefore, when the patients sexual partner is or may become pregnant, the patient should either avoid exposure of his partner to semen (e.g. by use of a condom) or discontinue Finasteride.

Tamsulosin Hydrochloride capsules are not indicated for use in women.

Contraindication

Hypersensitivity to any component of this medication. Finasteride use is also contraindicated in women and paediatric patient

History of orthostatic hypotension. Severe hepatic impairment.

Special Warning

Renal insufficiency: Dosage adjustments are not necessary in patients with renal insufficiency since pharmacokinetic studies did not indicate any change in the disposition of Finasteride.

Hepatic insufficiency: There are no data available in patients with hepatic insufficiency.

Elderly: No dosage adjustment is required in elderly patients.

Tamsulosin Hydrochloride capsules are not indicated for use in pediatric populations.

Acute Overdose

As overdose of Tamsulosin Hydrochloride capsules lead to hypotension, support the cardiovascular system is of first importance. Restoration of blood pressure and normalization of heart rate may be accomplished by keeping the patient in supine position. If this measure is inadequate, then administration of intravenous fuid should be considered. Measures, such as emesis, can be taken to impede absorption. When large quantities are involved, gastric lavage can be applied and activated charcoal and an osmotic laxative, such as sodium sulphate, can be administered.