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Flomax 0.4 mg capsule: Flomax Uses, Dosage, Side Effects & Warnings

Generic Flomax Availability – Drugs.com



Last updated on May 11, 2023.

Flomax is a brand name of tamsulosin, approved by the FDA in the following formulation(s):

FLOMAX (tamsulosin hydrochloride – capsule;oral)

  • Manufacturer: SANOFI
    Approval date: April 15, 1997
    Strength(s): 0.4MG [RLD][AB]

Has a generic version of Flomax been approved?

Yes. The following products are equivalent to Flomax:

tamsulosin hydrochloride capsule;oral

  • Manufacturer: ALKEM LABS LTD
    Approval date: August 11, 2017
    Strength(s): 0.4MG [AB]
  • Manufacturer: ANBISON LAB
    Approval date: October 17, 2019
    Strength(s): 0.4MG [AB]
  • Manufacturer: AUROBINDO PHARMA LTD
    Approval date: April 30, 2013
    Strength(s): 0.4MG [AB]
  • Manufacturer: IMPAX LABS
    Approval date: March 2, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: MACLEODS PHARMS LTD
    Approval date: January 20, 2017
    Strength(s): 0. 4MG [AB]
  • Manufacturer: SANDOZ
    Approval date: April 27, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: SUN PHARM INDS LTD
    Approval date: July 15, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: SYNTHON PHARMS
    Approval date: April 27, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: TEVA PHARMS
    Approval date: April 27, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: WOCKHARDT
    Approval date: April 27, 2010
    Strength(s): 0.4MG [AB]
  • Manufacturer: ZYDUS PHARMS USA INC
    Approval date: April 27, 2010
    Strength(s): 0.4MG [AB]

Note: Fraudulent online pharmacies may attempt to sell an illegal generic version of Flomax. These medications may be counterfeit and potentially unsafe. If you purchase medications online, be sure you are buying from a reputable and valid online pharmacy. Ask your health care provider for advice if you are unsure about the online purchase of any medication.

See also: Generic Drug FAQ.

More about Flomax (tamsulosin)

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Professional resources

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Related treatment guides

  • Benign Prostatic Hyperplasia

Drug PatentA drug patent is assigned by the U.S. Patent and Trademark Office and assigns exclusive legal right to the patent holder to protect the proprietary chemical formulation. The patent assigns exclusive legal right to the inventor or patent holder, and may include entities such as the drug brand name, trademark, product dosage form, ingredient formulation, or manufacturing process A patent usually expires 20 years from the date of filing, but can be variable based on many factors, including development of new formulations of the original chemical, and patent infringement litigation.
Drug ExclusivityExclusivity is the sole marketing rights granted by the FDA to a manufacturer upon the approval of a drug and may run simultaneously with a patent. Exclusivity periods can run from 180 days to seven years depending upon the circumstance of the exclusivity grant.
RLDA Reference Listed Drug (RLD) is an approved drug product to which new generic versions are compared to show that they are bioequivalent. A drug company seeking approval to market a generic equivalent must refer to the Reference Listed Drug in its Abbreviated New Drug Application (ANDA). By designating a single reference listed drug as the standard to which all generic versions must be shown to be bioequivalent, FDA hopes to avoid possible significant variations among generic drugs and their brand name counterpart.
ABProducts meeting necessary bioequivalence requirements. Multisource drug products listed under the same heading (e.g. identical active ingredients, dosage form, and routes of administration) and having the same strength (see Therapeutic Equivalence-Related Terms, Pharmaceutical Equivalents) generally will be coded AB if a study is submitted demonstrating bioequivalence. In certain instances, a number is added to the end of the AB code to make a three character code (e.g. AB1, AB2, AB7). Three-character codes are assigned only in situations when more than one reference listed drug of the same strength has been designated under the same heading. Two or more reference listed drugs are generally selected only when there are at least two potential reference drug products which are not bioequivalent to each other. If a study is submitted that demonstrates bioequivalence to a specific listed drug product, the generic product will be given the same three-character code as the reference listed drug it was compared against.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Flomax Interactions Checker – Drugs.com



There are 286 drugs known to interact with
Flomax (tamsulosin), along with
4 disease interactions, and 2 alcohol/food interactions.

Of the total drug interactions,
32 are major, 250 are moderate, and 4 are minor.

Does Flomax interact with my other drugs?

Enter other medications to view a detailed report.

  • View all 286 medications that may interact with Flomax
  • View Flomax alcohol/food interactions (2)
  • View Flomax disease interactions (4)

Most frequently checked interactions

View interaction reports for Flomax (tamsulosin) and the medicines listed below.

  • Major
  • Moderate
  • Minor
  • Unknown
  • allopurinol
  • amlodipine
  • aspirin
  • Aspirin Low Strength (aspirin)
  • atorvastatin
  • Crestor (rosuvastatin)
  • Cymbalta (duloxetine)
  • finasteride
  • furosemide
  • gabapentin
  • hydrochlorothiazide
  • Lasix (furosemide)
  • levothyroxine
  • Lipitor (atorvastatin)
  • lisinopril
  • losartan
  • metformin
  • metoprolol
  • multivitamin
  • omeprazole
  • Plavix (clopidogrel)
  • prednisone
  • simvastatin
  • Synthroid (levothyroxine)
  • tramadol
  • trazodone
  • Tylenol (acetaminophen)
  • Vitamin B12 (cyanocobalamin)
  • Vitamin C (ascorbic acid)
  • Vitamin D3 (cholecalciferol)

Flomax alcohol/food interactions

There are 2 alcohol/food interactions with Flomax (tamsulosin).

Flomax disease interactions

There are 4 disease interactions with Flomax (tamsulosin) which include:

  • glaucoma
  • hypotension
  • end-stage renal disease
  • severe liver disease

Report options


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More about Flomax (tamsulosin)

  • Flomax consumer information
  • Compare alternatives
  • Pricing & coupons
  • Reviews (289)
  • Drug images
  • Side effects
  • Dosage information
  • Patient tips
  • During pregnancy
  • Generic availability
  • Support group
  • Drug class: alpha-adrenoreceptor antagonists
  • Breastfeeding
  • En español

Related treatment guides

  • Benign Prostatic Hyperplasia

Drug Interaction Classification
These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
MajorHighly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
ModerateModerately clinically significant. Usually avoid combinations; use it only under special circumstances.
MinorMinimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
UnknownNo interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Omnik: instruction, price, analogues | modified release hard capsules Astellas Pharma Europe


  • Pharmacological properties
  • Indications Omnic
  • Application Omnic
  • Contraindications
  • Side effects
  • Special instructions
  • Interactions
  • Overdose
  • Storage conditions
  • Diagnosis
  • Recommended alternatives
  • Trade names

pharmacodynamics. Omnic selectively and competitively blocks postsynaptic α 1 -adrenergic receptors, in particular α 1A and α 1D located in the smooth muscles of the prostate gland, bladder neck and prostatic urethra. This leads to a decrease in the tone of the smooth muscles of the prostate gland, the neck of the bladder and the prostate part of the urethra and an improvement in the outflow of urine. At the same time, it reduces the severity of symptoms of obstruction and irritation caused by benign prostatic hyperplasia (difficulty starting urination, weakening the urine stream, dripping after urination, a feeling of incomplete emptying of the bladder, frequent urge to urinate, urge to urinate at night, imperative urge to urinate) .

These effects are long-lasting with long-term treatment and greatly discourage surgery or catheterization.

Antagonists α 1 -adrenergic receptors have the ability to reduce blood pressure by reducing peripheral vascular tone. When conducting studies of the drug Omnic, there was no clinically significant decrease in blood pressure.

Pharmacokinetics. Absorption : Tamsulosin is well absorbed from the gastrointestinal tract, and its bioavailability is almost 100%. Absorption of tamsulosin occurs somewhat more slowly after a meal. Homogeneity of absorption is achieved when the patient uses Omnic at the same time after a meal. The pharmacokinetics of tamsulosin is linear.

After taking a single dose of the drug Omnic after meals C max tamsulosin in blood plasma is reached after about 6 hours, and a stable concentration – on the 5th day after daily administration of the drug. C max is approximately ⅔ higher than that achieved after taking a single dose.

Distribution: in men, tamsulosin is approximately 99% bound to plasma proteins. The volume of distribution of the drug is insignificant (about 0.2 l / kg).

Metabolism: tamsulosin hydrochloride is not subject to the first pass effect and is slowly metabolized in the liver to form pharmacologically active metabolites that retain high selectivity for α 1 -adrenergic receptors. Most of the active substance is present in the blood unchanged.

Elimination: tamsulosin and its metabolites are excreted primarily in the urine. About 9% of the dose remains in the form of unchanged active substance.

After a single dose of the drug Omnic after meals and at a stable plasma concentration T ½ is approximately 10 and 13 hours, respectively.

treatment of functional disorders of the lower urinary tract in benign prostatic hyperplasia.

The recommended dose for adults is 1 capsule per day after breakfast daily or after the first meal. The capsule should be swallowed whole and not broken or chewed as this will prevent the modified release of the active ingredient.

Dose adjustment is not required in patients with renal insufficiency. Dose adjustment is not required in patients with moderate to moderate hepatic impairment (see CONTRAINDICATIONS).

hypersensitivity to tamsulosin hydrochloride, including drug-induced angioedema, or to any of the excipients; a history of orthostatic hypotension; severe liver failure.



Often (>1/100, <1/10) Uncommon (>1/1000, <1/100) Rare (>1/10,000, <1/1000) Very rare (<1/10,000) Unknown (cannot be estimated with the following data)
Neurological disorders Dizziness (1.3%) Headache Fainting
Vision side Blurred vision*, blurred vision*
Cardiac side Palpitation sensation




Respiratory-mediastinal disorders Rhinitis Epistaxis*
Gastrointestinal disorders Constipation, diarrhea, nausea, vomiting
Skin and mucous membranes Rash, itching, urticaria Angioedema Stevens-Johnson Syndrome Erythema multiforme*, exfoliative dermatitis*
Reproductive disorders Ejaculatory disorders, including retrograde ejaculation and failure


General violations Asthenia

*Noted in the post-registration period.

There have been post-marketing reports of intraoperative iris instability (constricted pupil syndrome) during cataract and glaucoma surgery in patients treated with tamsulosin (see SPECIAL INSTRUCTIONS).

Post-marketing experience : in addition to the above adverse reactions, cases of atrial fibrillation, arrhythmia, tachycardia and dyspnoea have been reported. Since these reports were spontaneous in nature, their frequency and the role of tamsulosin cannot be reliably established.

As with other α 1 -adrenergic blockers, in some cases, when using Omnic, a decrease in blood pressure is possible, which can sometimes lead to loss of consciousness. When the first signs of orthostatic hypotension (dizziness, weakness) appear, the patient should take a horizontal position until the above symptoms disappear.

Before starting treatment with Omnic, a medical examination should be performed to look for other comorbid conditions that may cause the same symptoms as benign prostatic hyperplasia. Before starting treatment, a rectal examination of the prostate gland and, if necessary, a prostate specific antigen (PSA) test should be performed before and at regular intervals during treatment.

Prescribe the drug to patients with severe renal insufficiency (creatinine clearance <10 ml / min) with extreme caution, since clinical studies with the use of the drug Omnic in such patients have not been conducted.

Some patients who have taken or are taking tamsulosin have experienced atonic pupil syndrome (a variant of constricted pupil syndrome) during cataract and glaucoma surgery, which may increase the number of complications during such surgery.

It is generally recommended to stop tamsulosin treatment 1-2 weeks before cataract and glaucoma surgery. However, the feasibility and timing of discontinuation of tamsulosin treatment has not yet been clearly established. Atonic pupil syndrome has also been reported in patients who discontinued tamsulosin for a long time prior to cataract surgery.

Initiation of tamsulosin hydrochloride is not recommended in patients prior to elective cataract or glaucoma surgery. In preparation for surgery, surgeons and ophthalmologists should be informed whether the patient has taken (or is taking) tamsulosin in order to prevent possible complications associated with atonic pupil syndrome.

Tamsulosin hydrochloride should not be used in combination with strong CYP3A4 inhibitors in patients with low CYP2D6 metabolism.

Tamsulosin hydrochloride should be used with caution in combination with strong and moderate inhibitors of CYP 3A4 (see Interactions).

Allergic reactions to tamsulosin have been reported in patients with a history of allergy to sulfonamides. Caution should be exercised when using tamsulosin hydrochloride in patients who have previously been allergic to sulfonamides.

Use during pregnancy and lactation. The drug is used only for the treatment of men.

Fertility. During clinical studies of tamsulosin, ejaculatory disorders have been noted for a short and long time. Cases of impaired ejaculation, retrograde ejaculation and insufficient ejaculation were recorded in the post-registration period.

Children. The drug is not used in children.

Ability to influence reaction rate when driving vehicles or working with other mechanisms . Studies of the effect of the drug on the ability to drive vehicles or operate other mechanisms have not been conducted. However, patients should be warned about the possibility of dizziness.

Interaction studies have been conducted in adults only.

Co-administration of tamsulosin hydrochloride with atenolol, enalapril or theophylline did not result in drug interactions. Simultaneous use with cimetidine increases, and with furosemide – reduces the concentration of tamsulosin in the blood plasma, but since these levels remain within the normal range, there is no need for a special dose adjustment of tamsulosin.

In vitro studies diazepam, propranolol, trichlormethiazide, chlormadinone, amitriptyline, diclofenac, glibenclamide, simvastatin and warfarin do not affect the free fraction of tamsulosin in human plasma. Similarly, tamsulosin does not alter the free fractions of diazepam, propranolol, trichlormethiazide, and chlormadinone in human plasma.

However, diclofenac and warfarin may increase the elimination rate of tamsulosin.

Concomitant use of tamsulosin hydrochloride with strong inhibitors of CYP 3A4 may increase the effect of tamsulosin hydrochloride. Simultaneous use with ketoconazole (a known potent inhibitor of CYP 3A4) led to an increase in AUC and an increase in C max to 2.8 and 2.2 respectively.

Tamsulosin hydrochloride should not be used in combination with strong CYP3A4 inhibitors in patients with low CYP2D6 metabolism.

The drug should be used with caution in combination with strong and moderate inhibitors of CYP 3A4.

Simultaneous use of tamsulosin hydrochloride and paroxetine (a powerful inhibitor of CYP 2D6) leads to an increase in C max and an increase in AUC to 1.3 and 1.6, respectively, but this is not clinically significant.

Simultaneous use with other blockers α 1 -adrenergic receptors may enhance the hypotensive effect.

symptoms . An overdose of tamsulosin can potentially cause a severe hypotensive effect. Severe hypotensive effect was noted at various degrees of overdose.

Treatment . In the event of a sharp decrease in blood pressure due to an overdose, maintenance therapy should be carried out aimed at restoring the normal function of the cardiovascular system (for example, the patient should take a horizontal position). If this measure does not work, it is necessary to carry out infusion therapy and prescribe vasopressors. Renal function should be monitored and general supportive therapy administered. Due to the high degree of binding of tamsulosin to plasma proteins, hemodialysis is hardly advisable.