Table of ContentsView AllTable of ContentsHow It WorksDosageHow Long It Takes to WorkSide EffectsInteractionsConsiderationsGenerics and Cost
Table of ContentsView All
View All
Table of Contents
How It Works
Dosage
How Long It Takes to Work
Side Effects
Interactions
Considerations
Generics and Cost
Flomax (tamsulosin hydrochloride) is a drug used totreat an enlarged prostateand chronic prostate inflammation. It is one of the most commonly prescribed drugs in older men and one of the 200 most prescribed drugs overall, according to the Pharmacy Technician Certification Board.
This article covers how Flomax works, what the dosage is, how long it takes to work, and common side effects.
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How Does Flomax Work?
Flomax is indicated to treat a number of common medical conditions in men, including:
Despite the fact that Flomax can decrease blood pressure, it is not approved for the treatment of hypertension (high blood pressure).
Flomax Dosage
Flomax is available in a 0.4-milligram (mg) capsule. It is taken daily approximately 30 minutesafter ameal, ideally at the same time every day.
If you miss a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and proceed as usual. Never take a double dose of Flomax, since this could lead to a steep drop in blood pressure (hypotension).
Many urologists today will prescribe Flomax as part of a dual therapy with 5-alpha reductase inhibitor—such as Proscar (finasteride) or Avodart (dutasteride).
A 2019 meta-analysis found that the combination of tamsulosin plus Avodart provides greater therapeutic effect for BPH. The combination has a higher incidence of sexual side effects, but can significantly reduce risk of BPH-related symptom progression and acute urinary retention relative to tamsulosin monotherapy.
How Long Does Flomax Take to Work?
Common Side Effects
Other more problematic side effects include dizziness, vertigo,postural hypotension(low blood pressure when rising), and fainting. Collectively known as orthostasis, these symptoms tend to occur within the first eight weeks of treatment. Due to its potential effect on blood pressure, people with low blood pressure, mechanical heart problems, or congestive heart failure should be monitored closely while taking Flomax.
Call your healthcare provider if your urination doesn’t improve within two weeks or you experience any severe, persistent, or worsening side effects like fainting or priapism.
Interactions and Contraindications
Flomax is contraindicated for use in people with a known allergy to Flomax or any of its components.
In some cases, your blood pressure may need to be monitored while on treatment. In others, one of the two drugs may need to be substituted.
Speak with your healthcare provider if you take any of the following:
Flomax should not be used in people with end-stage kidney failure. People with kidney impairment should also be regularly monitored due to increased risk of an exaggerated hypotensive response.
If you are scheduled to havecataractor glaucoma surgery, tell your healthcare provider if you are either using or have recently used Flomax.A serious eye disorder called intraoperative floppy iris syndrome has been known to occur in around 2% of those who have undergone cataract surgery while on Flomax.
As such, Flomax is not recommended for use prior to cataract surgery due to studies showing an increased risk of adetached retinaor lost lens.
Flomax is not indicated for use in females.Due to its potential impact on blood pressure, it is important to advise your healthcare provider if you have dizziness while taking Flomax. Take care when rising from bed in the morning to avoid falling or blacking out. The same applies if you are planning to drive given the risk of vision impairment and dizziness. In some cases, treatment may need to be stopped if the drug interferes with your ability to function normally.
Because BPH may overlap withprostate cancer, people with prostate problems shouldundergo teststo rule out cancer before starting treatment and at regular intervals afterward.
For its part, Boehringer Ingelheim offers the brand name Flomax at anonline priceof $35 for 30 capsules or $90 for 90 capsules with free home delivery.
6 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Food and Drug Administration.Flomax label.Zhou Z, Cui Y, Wu J, Ding R, Cai T, Gao Z.Meta-analysis of the efficacy and safety of combination of tamsulosin plus dutasteride compared with tamsulosin monotherapy in treating benign prostatic hyperplasia.BMC Urol. 2019;19(1):17. doi:10.1186/s12894-019-0446-8Food and Drug Administration.JALYN (dutasteride and tamsulosin hydrochloride) capsules.Food and Drug Administration.Flomax label.U.S. Food and Drug Administration.Approval letter (tamsulosin hydrochloride).Drugs.com.Tamsulosin prices, coupons, and patient programs.Additional ReadingRoehrborn C, Siami P, Barkin J, et al.The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study.Eur Urology.2010;57(1):123-31. doi:10.1016/j.eururo.2009.09.035U.S. Food and Drug Administration.Highlights of prescribing information: Flomax (tamsulosin hydrochloride) Capsules, 0.4 mg.
6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Food and Drug Administration.Flomax label.Zhou Z, Cui Y, Wu J, Ding R, Cai T, Gao Z.Meta-analysis of the efficacy and safety of combination of tamsulosin plus dutasteride compared with tamsulosin monotherapy in treating benign prostatic hyperplasia.BMC Urol. 2019;19(1):17. doi:10.1186/s12894-019-0446-8Food and Drug Administration.JALYN (dutasteride and tamsulosin hydrochloride) capsules.Food and Drug Administration.Flomax label.U.S. Food and Drug Administration.Approval letter (tamsulosin hydrochloride).Drugs.com.Tamsulosin prices, coupons, and patient programs.Additional ReadingRoehrborn C, Siami P, Barkin J, et al.The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study.Eur Urology.2010;57(1):123-31. doi:10.1016/j.eururo.2009.09.035U.S. Food and Drug Administration.Highlights of prescribing information: Flomax (tamsulosin hydrochloride) Capsules, 0.4 mg.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Food and Drug Administration.Flomax label.Zhou Z, Cui Y, Wu J, Ding R, Cai T, Gao Z.Meta-analysis of the efficacy and safety of combination of tamsulosin plus dutasteride compared with tamsulosin monotherapy in treating benign prostatic hyperplasia.BMC Urol. 2019;19(1):17. doi:10.1186/s12894-019-0446-8Food and Drug Administration.JALYN (dutasteride and tamsulosin hydrochloride) capsules.Food and Drug Administration.Flomax label.U.S. Food and Drug Administration.Approval letter (tamsulosin hydrochloride).Drugs.com.Tamsulosin prices, coupons, and patient programs.
Food and Drug Administration.Flomax label.
Zhou Z, Cui Y, Wu J, Ding R, Cai T, Gao Z.Meta-analysis of the efficacy and safety of combination of tamsulosin plus dutasteride compared with tamsulosin monotherapy in treating benign prostatic hyperplasia.BMC Urol. 2019;19(1):17. doi:10.1186/s12894-019-0446-8
Food and Drug Administration.JALYN (dutasteride and tamsulosin hydrochloride) capsules.
U.S. Food and Drug Administration.Approval letter (tamsulosin hydrochloride).
Drugs.com.Tamsulosin prices, coupons, and patient programs.
Roehrborn C, Siami P, Barkin J, et al.The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study.Eur Urology.2010;57(1):123-31. doi:10.1016/j.eururo.2009.09.035U.S. Food and Drug Administration.Highlights of prescribing information: Flomax (tamsulosin hydrochloride) Capsules, 0.4 mg.
Roehrborn C, Siami P, Barkin J, et al.The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study.Eur Urology.2010;57(1):123-31. doi:10.1016/j.eururo.2009.09.035
U.S. Food and Drug Administration.Highlights of prescribing information: Flomax (tamsulosin hydrochloride) Capsules, 0.4 mg.
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