Tamsulosin was approved for medical use in the United States in 1997.[6] It is available as a generic medication.[9] In 2021, it was the 24th most commonly prescribed medication in the United States, with more than 23million prescriptions.[11][12]
Medical uses
Flomax 0.4 mg oral capsule
Tamsulosin is primarily used for benign prostatic hyperplasia (BPH) and to help with the passage of kidney stones.[13][14] Tamsulosin, however, appears to be effective only for stones over 4 mm and less than 10 mm in size.[8]
Tamsulosin is also used as an add-on treatment for acute urinary retention. People may void more successfully after catheter removal if they are taking tamsulosin. People taking tamsulosin also are less likely to need recatheterization.[15]
Tamsulosin does not decrease the overall size of the prostate in men with BPH, and is not recommended for prevention of prostate cancer.[16]
Combination therapy
The results of the CombAT (combination of dutasteride (Avodart) and tamsulosin, under the brand name Duodart) trial in 2008 demonstrated that treatment with the combination of dutasteride and tamsulosin provides greater symptom benefits compared to monotherapy with either agent alone for treatment of benign prostatic hyperplasia.[17]
The CombAT trial became the medication Jalyn. It was approved by the FDA on 14 June 2010.[18] This combination can be useful because it may take up to six months for symptomatic relief to be found when using 5-alpha-reductase inhibitors such as dutasteride compared to alpha-1 receptor blockers, which can provide relief in some cases within 48 hours.[19]
Adverse effects
Eyes: People taking tamsulosin are prone to a complication known as floppy iris syndrome during cataract surgery. Adverse outcomes of the surgery are greatly reduced by the surgeon's prior knowledge of the person's history with this drug, and thus having the option of alternative techniques.[20]
Persons with cardiac conditions including hypotension, mechanical heart failure (valvular, pulmonary embolism, pericarditis), and congestive heart failure should be monitored carefully while taking tamsulosin.
Alpha blockers, including prazosin, terazosin, doxazosin, or tamsulosin, do not appear to affect all-cause mortality in heart failure rehospitalization in those also receiving β-blockers.[23]
Tamsulosin can also cause retrograde ejaculation, which occurs when semen is redirected to the urinary bladder instead of being ejaculated normally. This is because tamsulosin relaxes the muscles of the urethral sphincters, which are normally closed during ejaculation.[24]
When alpha 1 receptors in the bladder neck, prostate, ureter, and urethra are blocked, a relaxation in smooth muscle tissue results.[16] This mechanism decreases resistance to urinary flow, reduces discomfort associated with BPH, and facilitates passage of kidney stones.[16]
Brand names
Tamsulosin was first marketed in 1996 under the trade name Flomax. The U.S. patent expired in October 2009.[26] The U.S. Food and Drug Administration (FDA) approved generics in March 2010.[27] In 2010, tamsulosin was available as OTC medication in UK.[28]
It is marketed by various companies under licence, including Boehringer Ingelheim and CSL. Tamsulosin hydrochloride extended-release capsules are marketed under the trade names Urimax 0.4 (India),Tamlocept 0.4 (India), Flomax, Flomaxtra, Contiflo XL, bestflo, Mecir LP (France), Urimax, Pamsvax, and Pradif,[29] although generic, unmodified-release capsules are still approved and marketed in many countries (such as Canada). Generic extended-release tablets are marketed in most countries of the EEA.[30] In Mexico, it is marketed as Secotex and as Harnal D in Japan and Indonesia and as Harnal OCAS (oral controlled absorption system) in Thailand.[31] In Egypt,[32]Italy, Russia and Iceland, it is marketed under the trade name Omnic by Astellas Pharma Europe. The largest manufacturer of tamsulosin is Synthon BV (the Netherlands). [citation needed] Tamsulosin hydrochloride is marketed in Bangladesh under the trade names Uromax, Prostanil MR, Tamisol MR, and Tamsin.[citation needed]
^Lucas MG, Stephenson TP, Nargund V (February 2005). "Tamsulosin in the management of patients in acute urinary retention from benign prostatic hyperplasia". BJU International. 95 (3): 354–357. doi:10.1111/j.1464-410X.2005.05299.x. PMID15679793. S2CID30254915.
^ abcLewis SM, Dirksen SR, Heitkemper MM, Bucher LH (2013). Medical-surgical nursing : assessment and management of clinical problems (9th ed.). St. Louis, Missouri. ISBN978-0-323-10089-2. OCLC228373703.((cite book)): CS1 maint: location missing publisher (link)
^Roehrborn CG, Siami P, Barkin J, Damião R, Major-Walker K, Morrill B, Montorsi F (February 2008). "The effects of dutasteride, tamsulosin and combination therapy on lower urinary tract symptoms in men with benign prostatic hyperplasia and prostatic enlargement: 2-year results from the CombAT study". The Journal of Urology. 179 (2): 616–621, discussion 621. doi:10.1016/j.juro.2007.09.084. PMID18082216.
