Flomax 0.4mg Capsules
It is used to treat the signs of an enlarged prostate. If you have been given this drug for some other reason, talk with your doctor for more information.
Drug Class
Drugs for Benign Prostatic Hyperplasia (BPH)
Pharmacologic Class
Alpha-1A Adrenergic Antagonist
Pregnancy Category
Category B
FDA Approved
Apr 1997
DEA Schedule
Not Controlled
Overview
What is this medicine?
Tamsulosin is a medication used to treat symptoms of an enlarged prostate (Benign Prostatic Hyperplasia or BPH) in men. It works by relaxing the muscles in the prostate and bladder, which helps to improve urine flow and reduce urinary symptoms like frequent urination, urgency, and difficulty starting urination.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Take your medication 30 minutes after the same meal every day to help your body absorb it consistently. Swallow the tablet whole - do not chew, open, or crush it.
Storing and Disposing of Your Medication
Keep your medication at room temperature in a dry place, away from the bathroom. Store all medications in a safe location, out of the reach of children and pets. When your medication is no longer needed or has expired, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. If you have questions about disposing of your medication, ask your pharmacist. You may also want to check if there are any drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and return to your regular schedule. Do not take two doses at the same time or take extra doses. If you miss taking your medication for several days in a row, contact your doctor before restarting your medication to ensure it's safe to do so.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Take your medication 30 minutes after the same meal every day to help your body absorb it consistently. Swallow the tablet whole - do not chew, open, or crush it.
Storing and Disposing of Your Medication
Keep your medication at room temperature in a dry place, away from the bathroom. Store all medications in a safe location, out of the reach of children and pets. When your medication is no longer needed or has expired, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. If you have questions about disposing of your medication, ask your pharmacist. You may also want to check if there are any drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and return to your regular schedule. Do not take two doses at the same time or take extra doses. If you miss taking your medication for several days in a row, contact your doctor before restarting your medication to ensure it's safe to do so.
Lifestyle & Tips
- Take the capsule whole, do not crush, chew, or open it.
- Take the medication approximately 30 minutes after the same meal each day to ensure consistent absorption.
- Avoid activities requiring mental alertness, such as driving or operating machinery, until you know how this medication affects you, especially after the first dose or a dose increase, due to the risk of dizziness or fainting.
- Rise slowly from a sitting or lying position to minimize dizziness or lightheadedness.
- Inform your eye doctor (ophthalmologist) that you are taking tamsulosin before any eye surgery (especially cataract or glaucoma surgery), as it can cause a condition called Intraoperative Floppy Iris Syndrome (IFIS).
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
0.4 mg orally once daily, approximately 30 minutes after the same meal each day.
Dose Range:
0.4 - 0.8 mg
Condition-Specific Dosing:
initialDose:
0.4 mg once daily
maintenanceDose:
May be increased to 0.8 mg once daily after 2 to 4 weeks if response is inadequate.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No dose adjustment necessary.
Moderate:
No dose adjustment necessary.
Severe:
Use with caution; studies in patients with end-stage renal disease (CrCl < 10 mL/min) are limited.
Dialysis:
Not specifically studied; use with caution.
Hepatic Impairment:
Mild:
No dose adjustment necessary.
Moderate:
No dose adjustment necessary.
Severe:
Use with caution; studies in patients with severe hepatic impairment are limited.
Confidence:
Medium
Pharmacology
Mechanism of Action
Tamsulosin is an alpha-1A adrenergic antagonist. It selectively blocks alpha-1A adrenergic receptors in the prostate, prostatic capsule, bladder neck, and prostatic urethra. Blockade of these receptors leads to relaxation of the smooth muscle in these tissues, resulting in improved urine flow and a reduction in the symptoms of benign prostatic hyperplasia (BPH).
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 90% (fasted state)
Tmax:
4-5 hours (fasted), 6-7 hours (fed)
FoodEffect:
Absorption is complete but rate and extent are reduced when taken with food. Consistent administration after the same meal is recommended.
Distribution:
Vd:
Approximately 16 L
ProteinBinding:
Approximately 94% to 99% (primarily to alpha-1 acid glycoprotein)
CnssPenetration:
Limited
Elimination:
HalfLife:
Plasma elimination half-life: 5 to 7 hours (single dose); Effective half-life: 9 to 15 hours (multiple doses)
Clearance:
Approximately 0.2 L/hr
ExcretionRoute:
Primarily urine (76%) and feces (21%)
Unchanged:
Less than 10% of the dose is excreted unchanged in urine.
Pharmacodynamics
OnsetOfAction:
Symptomatic improvement may be seen within 1-2 weeks, with full effect potentially taking 2-4 weeks.
PeakEffect:
Peak symptomatic improvement typically observed after 2-4 weeks of therapy.
DurationOfAction:
24 hours (due to once-daily dosing)
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Fever, chills, or sore throat
Ejaculation problems
Painful erection (hard penis) or an erection that lasts longer than 4 hours, which may occur even when not having sex. If left untreated, this can lead to lasting sexual problems and impotence.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they persist or bother you:
Headache
Back pain
Diarrhea
Dizziness, tiredness, or weakness
Runny nose
* Throat irritation
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Fever, chills, or sore throat
Ejaculation problems
Painful erection (hard penis) or an erection that lasts longer than 4 hours, which may occur even when not having sex. If left untreated, this can lead to lasting sexual problems and impotence.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they persist or bother you:
Headache
Back pain
Diarrhea
Dizziness, tiredness, or weakness
Runny nose
* Throat irritation
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting (syncope)
- Chest pain
- Prolonged, painful erection (priapism) lasting more than 4 hours (seek immediate medical attention)
- Severe allergic reaction (rash, itching, swelling of face/tongue/throat, severe dizziness, trouble breathing)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. Certain medications, such as those used to treat HIV, infections, depression, and other conditions, should not be taken with this drug. Your doctor or pharmacist can advise you on potential interactions.
If you are taking a similar medication or have taken one in the past. If you are unsure, consult your doctor or pharmacist for clarification.
Your pregnancy or breastfeeding status, as this medication is not approved for use in these situations. If you are pregnant, plan to become pregnant, or are breastfeeding, discuss your options with your doctor.
This list is not exhaustive, and it is crucial to disclose all your medications and health issues to your doctor and pharmacist. They will help you determine whether it is safe to take this medication with your existing treatments and health conditions. Never start, stop, or modify the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. Certain medications, such as those used to treat HIV, infections, depression, and other conditions, should not be taken with this drug. Your doctor or pharmacist can advise you on potential interactions.
If you are taking a similar medication or have taken one in the past. If you are unsure, consult your doctor or pharmacist for clarification.
Your pregnancy or breastfeeding status, as this medication is not approved for use in these situations. If you are pregnant, plan to become pregnant, or are breastfeeding, discuss your options with your doctor.
This list is not exhaustive, and it is crucial to disclose all your medications and health issues to your doctor and pharmacist. They will help you determine whether it is safe to take this medication with your existing treatments and health conditions. Never start, stop, or modify the dosage of any medication without first consulting your doctor.
Precautions & Cautions
Important Warnings and Precautions for Patients Taking This Medication
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent potential interactions with other treatments.
Caution with Daily Activities
Until you know how this medication affects you, avoid driving and other activities that require your full attention. To minimize the risk of dizziness or fainting, get up slowly from a sitting or lying position, and be cautious when climbing stairs.
Special Considerations
If you are scheduled to undergo cataract surgery or any other eye procedure, discuss this with your doctor. Additionally, monitor your blood pressure as directed by your healthcare provider.
Specific Requirements for Certain Conditions
If you are taking this medication for an enlarged prostate, follow your doctor's instructions for regular rectal exams (to check the prostate gland) and blood tests (PSA tests).
Allergy Alert
If you have a known allergy to sulfa (sulfonamide) medications, consult your doctor before taking this medication.
Use in Children
This medication is not approved for use in children. However, in some cases, your child's doctor may decide that the benefits of taking this medication outweigh the risks. If your child has been prescribed this medication, ask their doctor about the potential benefits and risks, and discuss any concerns you may have.
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent potential interactions with other treatments.
Caution with Daily Activities
Until you know how this medication affects you, avoid driving and other activities that require your full attention. To minimize the risk of dizziness or fainting, get up slowly from a sitting or lying position, and be cautious when climbing stairs.
Special Considerations
If you are scheduled to undergo cataract surgery or any other eye procedure, discuss this with your doctor. Additionally, monitor your blood pressure as directed by your healthcare provider.
Specific Requirements for Certain Conditions
If you are taking this medication for an enlarged prostate, follow your doctor's instructions for regular rectal exams (to check the prostate gland) and blood tests (PSA tests).
Allergy Alert
If you have a known allergy to sulfa (sulfonamide) medications, consult your doctor before taking this medication.
Use in Children
This medication is not approved for use in children. However, in some cases, your child's doctor may decide that the benefits of taking this medication outweigh the risks. If your child has been prescribed this medication, ask their doctor about the potential benefits and risks, and discuss any concerns you may have.
Overdose Information
Overdose Symptoms:
- Severe hypotension (low blood pressure)
- Dizziness
- Weakness
- Fainting
What to Do:
In case of overdose, contact a poison control center immediately. Call 1-800-222-1222. Supportive measures should be taken to restore blood pressure and heart rate. The patient should be kept in a supine position. If necessary, vasopressors and/or volume expanders may be used. Dialysis is unlikely to be beneficial due to high protein binding.
Drug Interactions
Major Interactions
- Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir, clarithromycin): May significantly increase tamsulosin exposure, leading to increased risk of hypotension. Co-administration is not recommended.
- Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine, quinidine): May significantly increase tamsulosin exposure. Co-administration is not recommended.
- Other alpha-adrenergic blocking agents (e.g., prazosin, doxazosin, terazosin): Concomitant use may lead to additive hypotensive effects.
Moderate Interactions
- PDE5 inhibitors (e.g., sildenafil, tadalafil, vardenafil): Concomitant use may lead to additive blood pressure lowering effects, potentially causing symptomatic hypotension. Use with caution, ensure patient is stable on alpha-blocker therapy before initiating PDE5 inhibitor at lowest dose.
- Moderate CYP3A4 inhibitors (e.g., erythromycin, diltiazem): May increase tamsulosin exposure. Use with caution.
- Warfarin: Limited data, but caution is advised due to potential for increased prothrombin time/INR. Monitor coagulation parameters.
Minor Interactions
- Cimetidine: May cause a slight increase in tamsulosin clearance.
- Furosemide: May cause a slight decrease in tamsulosin clearance.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and assess risk of orthostatic hypotension.
Timing: Before initiating therapy.
Prostate-Specific Antigen (PSA)
Rationale: To rule out prostate cancer, as BPH symptoms can mimic prostate cancer. Tamsulosin does not affect PSA levels.
Timing: Before initiating therapy, if indicated for prostate cancer screening.
International Prostate Symptom Score (IPSS) or AUA Symptom Score
Rationale: To establish baseline symptom severity and track treatment efficacy.
Timing: Before initiating therapy.
Routine Monitoring
Blood Pressure (BP) - especially orthostatic
Frequency: Periodically, especially during dose titration or if symptoms of hypotension occur.
Target: Maintain within patient's normal range, avoid symptomatic orthostasis.
Action Threshold: Symptomatic orthostatic hypotension (dizziness, lightheadedness, syncope).
International Prostate Symptom Score (IPSS) or AUA Symptom Score
Frequency: Every 3-6 months, or as clinically indicated.
Target: Reduction in symptom score.
Action Threshold: Inadequate symptom improvement after 2-4 weeks at 0.4 mg (consider increasing to 0.8 mg).
Symptom Monitoring
- Dizziness
- Lightheadedness
- Syncope (fainting)
- Headache
- Nasal congestion
- Abnormal ejaculation
- Priapism (prolonged erection)
- Symptoms of BPH (urinary frequency, urgency, nocturia, weak stream, incomplete emptying)
Special Patient Groups
Pregnancy
Tamsulosin is not indicated for use in women. Pregnancy Category B based on animal studies, but clinical relevance for human pregnancy is not established as it's for male-specific conditions.
Trimester-Specific Risks:
First Trimester:
Not applicable (not indicated for women)
Second Trimester:
Not applicable (not indicated for women)
Third Trimester:
Not applicable (not indicated for women)
Lactation
Tamsulosin is not indicated for use in women. It is unknown if tamsulosin is excreted in human milk.
Infant Risk:
Not applicable (not indicated for women)
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Tamsulosin is not indicated for use in pediatric patients.
Geriatric Use
No overall differences in safety or effectiveness were observed between elderly (âĨ65 years) and younger patients. However, the incidence of dizziness and orthostatic hypotension may be higher in the elderly. Dose adjustment is generally not required based on age alone.
Clinical Information
Clinical Pearls
- Tamsulosin is an alpha-1A selective blocker, which theoretically leads to fewer systemic blood pressure effects compared to non-selective alpha-blockers, but orthostatic hypotension can still occur.
- Advise patients to take the medication consistently after the same meal each day to optimize absorption and minimize variability.
- Counsel patients about the risk of Intraoperative Floppy Iris Syndrome (IFIS) during cataract or glaucoma surgery and to inform their ophthalmologist about tamsulosin use.
- Priapism (prolonged erection) is a rare but serious side effect requiring immediate medical attention.
- While primarily for BPH, tamsulosin is sometimes used off-label for ureteral stone expulsion, though evidence varies.
Alternative Therapies
- Other alpha-blockers: Alfuzosin (Uroxatral), Doxazosin (Cardura), Silodosin (Rapaflo), Terazosin (Hytrin).
- 5-alpha reductase inhibitors: Finasteride (Proscar), Dutasteride (Avodart) - for larger prostates, take longer to work.
- PDE5 inhibitors: Tadalafil (Cialis) - approved for BPH symptoms.
- Anticholinergics (e.g., oxybutynin, tolterodine) - for overactive bladder symptoms, sometimes used in combination with alpha-blockers for storage symptoms.
- Beta-3 adrenergic agonists: Mirabegron (Myrbetriq) - for overactive bladder symptoms.
- Surgical options: TURP (Transurethral Resection of the Prostate), laser therapies, UroLift, Rezum.
Cost & Coverage
Average Cost:
$10 - $30 per 30 capsules (generic 0.4mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist. If you have any questions or concerns about this medication, don't hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide detailed information, including the name of the medication taken, the amount, and the time it occurred.