What Is Tamsulosin?

This product is a drug for the treatment of benign prostatic hyperplasia (BPH). It is a selective 1 adrenergic receptor blocker. Its main mechanism of action is to selectively block 1A adrenergic receptors in the prostate, relax the smooth muscles of the prostate, thereby improving Symptoms such as dysuria caused by benign prostatic hyperplasia.

Chinese name: Tansorosin
Foreign name: tamsulosin
Product name: Halle
main ingredient: Tansorosin

Molecular formula: C20H28N2O5S
Molecular weight: 408.51200
Character: White crystal
Attend: Benign prostatic hyperplasia

Tamsulosin Basic Information

Chinese name: Tansoloxin

Chinese alias: (R) -5 [2- [2- (2-ethoxyphenoxy)] ethylamino] propyl] -2-methoxy-benzenesulfonamide; tamsulosin 2-hydroxy Phenylacetone; tamsulosin; tamsulosin hydrochloride (tamsulosin hydrochloride);

English name: tamsulosin

English alias: Tamsulosinum; [14C] -Tamsulosin; Tamsulosina [INN-Spanish]; Tamsulosina; Tamsulosine;

CAS number: 106133-20-4

Molecular formula: C20H28N2O5S

Molecular weight: 408.51200

Exact mass: 408.17200

PSA: 108.26000

LogP: 4.51290

Tamsulosin physical and chemical properties

Appearance and properties: white crystal

Density: 1.191 g / cm3

Melting point: 226-228ºC

Boiling point: 595.5ºC at 760 mmHg

Flash point: 313.9ºC

Refractive index: 1.553

Vapor pressure: 3.79E-14mmHg at 25 ° C ^[1]

Tamsulosin Related Drug Information

Tamsulosin Classification

Urology medications> Prostate hyperplasia medications

Tamsulosin dosage form

Sustained-release capsules: 0.1mg, 0.2mg. Storage method: sealed.

Pharmacological effects of tamsulosin

1. It can selectively block the 1 receptor, and its affinity for the 1 receptor is 5400-24000 times stronger than that for the 2 receptor. This feature can enhance its efficacy and reduce adverse reactions.

2. Because the alpha receptors present in the urethra, bladder neck and prostate are mainly 1A receptors, tamsulosin has a highly selective blocking effect on the urethra, bladder neck and prostate smooth muscle, and its ability to inhibit the rise of internal pressure Is 13 times the ability to inhibit the rise of vasodilation, so the efficacy of tamsulosin is obvious and it can reduce the risk of orthostatic hypotension after taking the medicine.

3. It can reduce the pressure of the prostate in the urethral pressure curve, but has no effect on the rhythmic bladder contraction and the bladder pressure curve.

Tamsulosin Pharmacokinetics

Tamsulosin oral capsules are sustained release. Adults took a single oral dose of 0.2 mg and reached a peak plasma concentration (5.99 ± 1.61) ng / ml after (5.50 ± 1.10) h. Continuous medication, blood concentration can reach steady state on the 4th day. The drug is metabolized by the liver. Its plasma protein binding rate is about 99%, its distribution volume is about 0.2L / Kg, and its elimination half-life is (8.12 ± 3.84) h. 70% to 75% of tamsulosin metabolites are excreted in the urine, and 25% to 30% are excreted in the intestines with feces.

Indications for tamsulosin

It is used to treat abnormal urination caused by benign prostatic hyperplasia (such as frequent urination, increased nocturia, dysuria, etc.). It is suitable for mild to moderate patients and those who do not cause severe dysuria.

Contraindications for tamsulosin

People who are allergic to tamsulosin.

Tamsulosin precautions

1. Use with caution (1) Patients with orthostatic hypotension. (2) Patients with coronary heart disease. (3) Those with renal insufficiency.

2. The effects of the drug on the elderly. Because elderly patients often have low renal function, full attention should be paid to observe the patient's condition after taking the drug. If the expected effect is not achieved, it should not be continued to increase and should be treated by other methods.

3. Effects of Drugs on Pregnancy The US Drug and Food Administration (FDA) rates tamsulosin's pregnancy safety level B.

4. The effect of drugs on breastfeeding is not clear.

5. Check and monitor before and after medication and during medication. Blood routine, liver function, blood pressure and heart rate should be monitored regularly during medication.

6. Before using tamsulosin treatment, the possibility of prostate cancer must be ruled out.

7. Tamsulosin mainly targets the urethra, bladder neck and prostate smooth muscle, and has no effect on reducing the volume of the prostate. If the prostate is too large and the symptoms of obstruction are obvious, it can be taken at the same time as a 5-alpha reductase inhibitor. Tamsulosin should not be taken alone in severe urinary retention.

8. Tamsulosin slow-release capsules should be swallowed whole, do not chew the particles in the capsule.

9. Although tamsulosin has very little effect on vascular smooth muscle, because patients are mostly elderly, it is advisable to take a short rest after taking the medicine.

10. When combined with -adrenergic blockers or antihypertensive drugs, close monitoring should be performed to prevent hypotension. When used in combination with beta-adrenergic blockers, the starting dose of tamsulosin should be less than the usual dose, and it is best to use it at bedtime.

11. Overuse of tamsulosin can lower blood pressure, so attention should be paid to the dosage.

12. If blood pressure drops during medication, appropriate measures such as reduction and discontinuation should be taken immediately; if rash appears, discontinue medication immediately.

13. Due to the symptoms associated with orthostatic hypotension (such as dizziness, etc.) during medication, it is not advisable to drive, manipulate machinery or perform dangerous operations during medication.

14. If the treatment effect is not obvious after taking the medicine, it should be replaced in time.

Tamsulosin adverse reactions to tamsulosin

1. Central nervous system: occasionally dizziness, burnout, staggering gait, etc.

2. Cardiovascular system: occasionally decreased blood pressure and accelerated heart rate.

3. Gastrointestinal tract: occasionally lack of appetite, difficulty swallowing, nausea, vomiting, upset stomach, abdominal pain, etc.

4. Liver: occasionally alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) are elevated, which can return to normal after stopping the drug.

5. Allergic reactions: occasional rash.

6. Others: occasional nasal congestion, edema, etc.

Tamsulosin

Take 0.2mg (or 0.4mg) once a day, after meals. It can be increased or decreased according to age and symptoms.

Tamsulosin interactions with tamsulosin

1. Combined with cimetidine, it can inhibit the metabolism of tamsulosin, increase the blood concentration of tamsulosin, and cause toxic reactions.

2. The first combination with -adrenergic blockers can often increase the risk of hypotension. Food reduces the absorption of tamsulosin, which reduces the bioavailability of tamsulosin. ^[2]