Uroflow

Each prolonged release tablet contains tamsulosin hydrochloride 0.4 mg equivalent to tamsulosin 0.367 mg.
Tamsulosin hydrochloride is an antagonist of alpha adrenoceptors in the prostate.
Tamsulosin hydrochloride is (-)-(R)-5[2-[[2-(o-Ethoxyphenoxy)ethyl]amino]propyl]-2methoxybenzene sulfonamide, monohydrochloride. Tamsulosin hydrochloride is a white crystalline powder that melts with decomposition at approximately 230°C. It is sparingly soluble in water and methanol, slightly soluble in glacial acetic acid and ethanol and practically insoluble in ether.
The empirical formula of tamsulosin hydrochloride is C₂₀H₂₈N₂O₅S HCl. The molecular weight is 444.98.
Excipients/Inactive Ingredients: Hypromellose, microcrystalline cellulose, carbomers, silica, anhydrous colloidal, red iron oxide, magnesium stearate, purified water.

Pharmacology: Pharmacodynamics: Tamsulosin is a member of sulfamoylphenethylamine-derivative substances. Tamsulosin as well as other drugs in the same pharmacologic class such as doxazosin, prazosin and terazosin are capable to reduce urinary obstruction, improve urinary flow rates and relieve  obstructive manifestations associated with BPH. Tamsulosin has a 7-38 times greater affinity for alpha_1a receptors located in vascular smooth muscles (e.g., prostate muscle), then alpha_1B receptors located in vascular smooth muscles. Blocking of such receptors is associated with decreased resistance of urinary flow, particularly in patients with symptomatic benign prostatic hyperplasia (BPH). In addition, such selectivity of tamsulosin results in reduced incidence of adverse cardiovascular events (e.g., syncope, dizziness, orthostatic hypotension).
Pharmacokinetics: Absorption: Tamsulosin has good oral bioavailability and reach the peak concentration at 4-5 hours after administration in fasting state or 6-7 hours in fed state for plain formulation. However, the rate and extent of absorption of Uroflow which are modified release tablets are not affected by food.
Distribution: Tamsulosin is widely distributed in various tissue. 94% to 99% of tamsulosin is bound to alpha-1 acid glycoprotein.
Metabolism and Elimination: Tamsulosin is extensively metabolized by hepatic CYP3A4 and 2D6 enzyme systems. The metabolites undergo conjugation to glucoronide or sulfate, then are excreted by urination. Only 21% of absorbed tamsulosin is excreted in the feces. Elimination half-life of tamsulosin is approximately 9 to 15 hours in healthy populations.

Uroflow is indicated as a symptomatic treatment for patients with benign prostatic hyperplasia (BPH) and may be a useful alternative to surgical correction of the hyperplasia particularly in patients who are not, candidates for or, willing to undergo such surgery.

General recommendation: The usual initial dose for adult patients is 0.4 mg once daily. Dosage may be increased to 0.8 mg daily as needed to achieve the desired improvement in clinical symptoms and/or urinary flow rates. Approximately 2-4 weeks may be necessary to assess the response before recommendation of subsequent dosage adjustment.
Dosage Adjustment in Renal Impairment: Protein binding of tamsulosin may be altered in patients with impaired renal function either mild to moderate (creatinine clearance of 30-70 mL/min per 1.73m²) or severe (creatinine clearance of 10 to less than 30 ml/min per 1.73 m²). However such changes are not warranted for dosage adjustment. Tamsulosin has not been studied in end-stage renal patients (creatinine clearance of less than 10 mL/min per 1.73 m²).
Dosage Adjustment in Hepatic Impairment: Although protein binding property, plasma concentrations and intrinsic clearance of tamsulosin may be altered in patients with impaired hepatic function. Dosage adjustment of tamsulosin is not necessary.
Administration: Uroflow is administered orally.
Although food may delay absorption, decreased bioavailability and decreased peak plasma concentration of tamsulosin, it is recommended that Uroflow can be taken with or without food. Uroflow should be swallowed whole, do not crush or chew the tablet.

One case of tamsulosin overdose (30 capsules of 0.4 mg) was reported with severe headache. Due to highly protein binding, tamsulosin is not readily dialyzable. Thus, symptomatic and supportive treatment should be administered as appropriate. There is no specific antidote for tamsulosin overdose. Restore blood pressure and normalize heart rate by keeping the patient supine. Treat shock with volume expanders or vasopressors, if necessary.

Uroflow is contraindicated in patients with known history of hypersensitivity to quinazolines or to any components of the product.

Prior initiation of tamsulosin therapy, the patient should be examined to exclude the possibility of other conditions such as prostate carcinoma, which can cause the same manifestations as BPH. Digital rectal examination and, when necessary, determination of prostate specific antigen (PSA) should be performed before treatment and at regular intervals afterwards.
Risk of Intraoperative Floppy Iris Syndrome (IFIS): IFIS have been observed during surgical phacoemulsification in some cataract patients those receiving alpha₁-adrenergic blocker therapy at the time of cataract surgery. A small number of reported cases discontinued such therapy mostly 2-14 days prior to surgery, but occasionally 5 weeks to 9 months. In patients who have received such agents and need surgical cataract management, other modified surgical techniques should be exercised with special precaution. Discontinuing tamsulosin 1-2 weeks prior to such operation is considered helpful, but clinical benefit of this approach has not been established.
Risk of Priapism: Cases of priapism in patients taking alpha1-adrenergic blockers have been reported rarely.
Risk of Cardiovascular Adverse Effects: Postural hypotension, dizziness, vertigo, or syncope may occur in tamsulosin treated patients. Starting with the lower dose and titrate slowly may be necessary and patients should be cautioned to be aware of such adverse effects as well as measures to take if the develop (e.g., sitting, laying down).
Risk of Sensitivity Reactions: Allergic reactions including rash, pruritus, urticaria and angioedema of the tongue, lips and face have been reported with positive challenge results in some patients receiving tamsulosin. Allergic reactions to tamsulosin reported rarely in patients with history of sulfonamide hypersensitivity. Use with caution in such patients with serious or life threatening reactions.

Pregnancy Category B: Tamsulosin is not indicated for use in pregnant and nursing women.

Tamsulosin is generally well tolerated. However, the following undesirable effects could be found.
Undesirable Effects with Incidence more than 10% including: Cardiovascular System: Orthostatic hypotension.
Central Nervous System: Headache, dizziness.
Genitourinary System: Abnormal ejaculation.
Respiratory System: Rhinitis.
Miscellaneous: Infection.
Undesirable Effects with Incidence 1% to 10% Including: Cardiovascular System: Chest pain.
Central Nervous System: Somnolence, insomnia, vertigo.
Endocrine & Metabolic System: Libido decrease.
Gastrointestinal System: Diarrhea, nausea, gum pain, toothache.
Neuromuscular and Skeletal System: Weakness, back pain.
Ocular System: Blurred vision.
Respiratory System: Pharyngitis, cough, sinusitis.
Undesirable Effects with Incidence less than 1% including: Allergic reactions (angioedema, pruritus, rash, urticaria, respiratory symptoms), constipation, hypotension, intraoperative floppy iris syndrome, lightheadedness, symptomatic orthostasis, palpitation, priapism, skin desquamation, syncope, vomiting.

Concomitant Use with Potent CYP Inhibitors/Inducers: Tamsulosin is metabolized by CYP3A4 and 2D6 enzyme systems. Thus, tamsulosin may have interactions with other medications which have high capability in inhibition or induction of such enzyme systems. Concomitant use of tamsulosin with potent CYP inhibitors such as cimetidine, clarithromycin, itraconazole, ketoconazole, verapamil and ritonavir may increase plasma levels of tamsulosin and potentiate cardiovascular toxicities of tamsulosin. Therefore, concomitant use with potent CYP inhibitors should be avoided.
Concomitant Use with Other Antihypertensive Agents: There was an increased incidence as well as severity of orthostatic hypotension when tamsulosin and other antihypertensive agents were administered together, other alpha-adrenergic blockers and beta-adrenergic blockers. Special precaution with routinely monitoring should be exercised.

Protect from light and moisture.
Store below 30°C in a dry place.
Shelf-Life: 2 years.

Drugs for Bladder & Prostate Disorders

G04CA02 - tamsulosin ; Belongs to the class of alpha-adrenoreceptor antagonists. Used in the treatment of benign prostatic hypertrophy.

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