Generic Name: tamsulosin (tam-SOO-loe-sin hye-droe-KLOR-ide) (Oral route)
Medically reviewed by Drugs.com. Last updated on Oct 3, 2020.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Benign Prostatic Hypertrophy Agent
Pharmacologic Class: Tamsulosin
Uses for Flomax
Tamsulosin is used to treat men who have symptoms of an enlarged prostate gland, which is also known as benign enlargement of the prostate (benign prostatic hyperplasia or BPH). Benign enlargement of the prostate is a problem that can occur in men as they get older. The prostate gland is located below the bladder. As the prostate gland enlarges, certain muscles in the gland may become tight and get in the way of the tube that drains urine from the bladder. This can cause problems in urinating, such as a need to urinate often, a weak stream when urinating, or a feeling of not being able to empty the bladder completely.
Tamsulosin helps relax the muscles in the prostate and the opening of the bladder. This may help increase the flow of urine or decrease the symptoms. However, tamsulosin will not shrink the prostate. The prostate may continue to get larger. This may cause the symptoms to become worse over time. Therefore, even though tamsulosin may lessen the problems caused by enlarged prostate now, surgery still may be needed in the future.
This medicine is available only with your doctor's prescription.
Before using Flomax
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Tamsulosin is not indicated for use in the pediatric population.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of tamsulosin in the elderly.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Allergy to sulfa drugs—Increased allergic reaction risk in patients with this condition.
- Hypotension (low blood pressure)—Use with caution. May make this condition worse.
- Kidney disease, severe or
- Liver disease, severe—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of Flomax
Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
This medicine comes with a patient information insert. Read and follow the instructions in the insert carefully. Ask your doctor if you have any questions.
Take the capsule approximately 30 minutes after the same meal each day. Swallow the capsule whole. Do not crush, chew, or open it.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (capsules):
- For benign prostatic hyperplasia:
- Adults—At first, 0.4 milligram (mg) once a day. Your doctor may increase your dose if needed.
- Children—Use is not recommended.
- For benign prostatic hyperplasia:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using Flomax
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.
Dizziness, lightheadedness, or fainting may occur after you take this medicine, especially when you get up from a lying or sitting position. Getting up slowly may help lessen this problem. If you feel dizzy, lie down so you do not faint. Then sit for a few moments before standing to prevent the dizziness from returning.
Because tamsulosin may cause some people to become dizzy or feel faint, make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.
This medicine may rarely cause a severe allergic reaction (swelling of face, tongue, or throat, difficulty breathing, and blistering of the skin. Check with your doctor immediately if this occurs.
You should seek medical attention right away if you experience a prolonged erection while using this medicine. This is an extremely rare unwanted effect that must be treated right away to prevent permanent erectile damage (impotence).
If you plan to have cataract or glaucoma surgery, tell your eye doctor (ophthalmologist) that you are taking this medicine or that you used this medicine in the past 9 months. A serious eye problem called Intraoperative Floppy Iris Syndrome (IFIS) has occurred in some patients who were taking this medicine or who had recently taken this medicine when they had cataract or glaucoma surgery.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Flomax side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Cough or hoarseness
- fever or chills
- lower back or side pain
- painful or difficult urination
- Chest pain
- Dizziness or lightheadedness
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- feeling of constant movement of self or surroundings
- painful or prolonged erection of the penis
- sensation of spinning
Incidence not known
- Blistering, peeling, or loosening of the skin
- blurred vision
- difficult or labored breathing
- fast, pounding, or irregular heartbeat or pulse
- joint or muscle pain
- large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- red skin lesions, often with a purple center
- red, irritated eyes
- sore throat
- sores, ulcers, or white spots in the mouth or on the lips
- tightness of the chest
- unusual tiredness or weakness
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Abnormal ejaculation
- back pain
- body aches or pain
- lack or loss of strength
- stuffy or runny nose
- tender, swollen glands in the neck
- trouble swallowing
- voice changes
- Decreased interest in sexual intercourse
- decreased sexual drive or performance
- inability to have or keep an erection
- increased cough
- loss in sexual ability, desire, drive, or performance
- pain or tenderness around the eyes and cheekbones
- sleepiness or unusual drowsiness
- tooth disorder
- trouble sleeping
Incidence not known
- hives or welts, skin rash
- redness of the skin
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about Flomax (tamsulosin)
- Side Effects
- During Pregnancy
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- En Español
- 137 Reviews
- Generic Availability
- Drug class: antiadrenergic agents, peripherally acting
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