Uses

What is dutasteride/tamsulosin used for?

Dutasteride/tamsulosin is commonly used for benign prostatic hyperplasia (BPH), a condition where the prostate gland is enlarged but not cancerous. When the prostate is enlarged, it squeezes the urethra. This may lead to problems with your bladder muscles and urination (peeing).

Dutasteride/tamsulosin is used to treat the symptoms of BPH, which may include the following.

  • Frequent need to pee
  • Urgent need to pee
  • Waking up overnight to pee 
  • Trouble getting your urine flow to start or stop
  • Urine stream that is weak, dribbles, or pauses
  • Feeling like your bladder is not empty after you pee

Dutasteride/tamsulosin may also be used for other conditions as determined by your healthcare provider.

How does dutasteride/tamsulosin work (mechanism of action)?

This medicine contains two active ingredients that work in different ways to treat BPH. Dutasteride stops your body from turning testosterone into dihydrotestosterone (DHT), which is a hormone that makes the prostate grow larger. This helps to reduce the size of the prostate. Tamsulosin works to relax the smooth muscles in your prostate and bladder. This helps improve the flow of urine and makes it easier to pee.

How is dutasteride/tamsulosin supplied (dosage forms)?

Dutasteride/tamsulosin is available as Jalyn and generic dutasteride/tamsulosin in the following dosage forms that are taken by mouth.

  • 0.5 mg/0.4 mg oral capsules

How should I store dutasteride/tamsulosin?

Dutasteride/tamsulosin should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C) for shorter periods of time, such as when transporting it. Store in a cool, dry place.

If dutasteride/tamsulosin is stored at high temperatures, the capsule may leak or change in color. To be safe, do not take or touch dutasteride/tamsulosin capsules that are leaking, discolored, or damaged. 

Side Effects

What are the most common side effects of dutasteride/tamsulosin?

The most common side effects of dutasteride/tamsulosin are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

There may be other side effects of dutasteride/tamsulosin that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of dutasteride/tamsulosin?

While less common, the most serious side effects of dutasteride/tamsulosin are described below, along with what to do if they happen.

Low Blood Pressure Upon Standing. Dutasteride/tamsulosin may cause a sudden drop in blood pressure upon standing up from a seated or lying position (orthostatic hypotension). This side effect is more common after the first dose of dutasteride/tamsulosin and after changes in dose. To help avoid injury, be careful not to get up too quickly. If you feel dizzy, sit or lie down right away until the dizziness stops, then take your time getting up again. Tell your healthcare provider if you have any of the following symptoms.

  • Dizziness, feeling lightheaded, or fainting upon standing
  • Blurred vision
  • Confusion
  • Feeling weak 

Painful, Prolonged Erection (Priapism). Dutasteride/tamsulosin may cause an unwanted erection that is persistent, painful, and that may occur without sexual arousal. Priapism may cause permanent damage to the penis. Stop taking dutasteride/tamsulosin and get emergency help right away if you have any of the following symptoms of priapism. 

  • Erection lasting for more than 4 hours 
  • Erection that is unrelated to sexual stimulation
  • Painful or tender penis

Risk of Prostate Cancer. While rare, dutasteride/tamsulosin may raise the risk of a serious form of prostate cancer that can spread quickly. Prostate cancer and BPH may cause similar symptoms, such as urination (peeing) problems. Get prostate cancer screening tests as recommended by your healthcare provider. And tell your healthcare provider right away if you have any of the following symptoms, especially if they are more frequent or severe than usual. 

  • Difficult, frequent, or painful urination
  • Bloody pee or semen
  • Pain in your back, pelvis, or hips that does not go away
  • Weight loss for no clear reason

Severe Allergic Reactions. Dutasteride/tamsulosin may cause allergic reactions, which can be serious. Stop taking dutasteride/tamsulosin and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Warnings & Precautions

Who should not take dutasteride/tamsulosin?

Allergies to Ingredients. People who are allergic to any of the following should not take dutasteride/tamsulosin.

  • Dutasteride
  • Tamsulosin
  • Jalyn
  • Any other medicine known as a 5-alpha-reductase inhibitor, such as finasteride (Proscar, Propecia)
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific dutasteride/tamsulosin products they stock.

Pregnancy. Do not take dutasteride/tamsulosin if you are pregnant or may be pregnant. If you become pregnant, contact your healthcare professional right away. See the Pregnancy section for more details.

What should I know about dutasteride/tamsulosin before taking it?

Do not take dutasteride/tamsulosin unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share dutasteride/tamsulosin with other people, even if they have the same condition as you. It may harm them.

Keep dutasteride/tamsulosin out of the reach of children.

Dutasteride/tamsulosin may cause dizziness. Do not drive or do other activities that require coordination until you know how dutasteride/tamsulosin affects you.

Do not chew, crush, or open dutasteride/tamsulosin capsules.

Dutasteride/tamsulosin may affect semen. You may have less semen than usual, and the number and activity of sperm may be reduced. These changes may continue after dutasteride/tamsulosin is stopped. It is unknown if these changes could affect your fertility (the ability to father a pregnancy). If you have any concerns or questions about this, talk to your healthcare provider before starting this medicine. 

People who are or may be pregnant should not touch medicines that contain dutasteride. This medicine can be absorbed through the skin and may harm an unborn baby. If skin contact occurs, wash the area right away with soap and water. 

Do not donate blood while taking dutasteride/tamsulosin or for at least 6 months after your last dose. This medicine stays in the blood for up to 6 months and could harm an unborn baby if someone who is pregnant receives donated blood that contains dutasteride.

Dutasteride/tamsulosin is commonly used to treat benign prostatic hyperplasia (BPH), which is non-cancerous enlargement of the prostate. In some cases, BPH can occur at the same time as prostate cancer. Your healthcare provider may recommend getting tested for prostate cancer before you start dutasteride/tamsulosin and getting regular screenings thereafter. 

Dutasteride/tamsulosin can lower the levels of prostate-specific antigen (PSA) in your blood. You should still get PSA tests to check for prostate cancer as advised by your healthcare provider. Dutasteride/tamsulosin does not help prevent prostate cancer.

What should I tell my healthcare provider before taking dutasteride/tamsulosin?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if dutasteride/tamsulosin is right for you.

In particular, make sure that you discuss any of the following.

Planned Eye Surgery. Taking medicines that contain tamsulosin may raise the risk of eye problems during or after cataract or glaucoma surgery. Tell your healthcare provider if you are planning to have eye surgery. They may recommend that you wait until after the surgery is over to start dutasteride/tamsulosin.

Severe Kidney Problems. Tell your healthcare provider if you have kidney problems now or in the past. It is not known if dutasteride/tamsulosin is safe to take if you have severe kidney problems. Your healthcare provider may not recommend dutasteride/tamsulosin if your kidneys are not working as well as they should be.

Liver Problems. Tell your healthcare provider if you have liver problems now or in the past. They may not prescribe dutasteride/tamsulosin if your liver is not working as well as it should be. It is not known if dutasteride/tamsulosin is safe to take if you have severe liver problems.

Low Blood Pressure. Taking dutasteride/tamsulosin may cause brief episodes of low blood pressure, which may result in dizziness or fainting. If you already have low blood pressure, this side effect may be more severe or more likely to occur. Tell your healthcare provider if you have problems with low blood pressure. They can determine if dutasteride/tamsulosin is safe for you to take.

Sulfa Allergy. While rare, some people that have a sulfa allergy may also be allergic to medicines that contain tamsulosin. A sulfa allergy is a rash or more serious reaction to sulfa, or sulfonamide, medicines. Examples of sulfa medicines include sulfamethoxazole, sulfadiazine silver, or sulfasalazine. Tell your healthcare provider if you have any allergies to medicines. They can help you decide if it is safe for you to take dutasteride/tamsulosin.

Other Medicines and Supplements. Dutasteride/tamsulosin may interact with other medicines and supplements. Before taking dutasteride/tamsulosin, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. Medicines that contain dutasteride may cause harm to an unborn baby if the medicine is taken or touched by someone who is pregnant. Tell your healthcare provider if you are or plan to become pregnant. If you become pregnant, stop taking dutasteride/tamsulosin and contact your healthcare provider right away. 

Breastfeeding. It is not known if dutasteride/tamsulosin passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed.

Interactions

Does dutasteride/tamsulosin interact with foods or drinks?

Your healthcare provider may recommend limiting or avoiding grapefruit while taking dutasteride/tamsulosin. Eating grapefruit or drinking grapefruit juice can increase your risk of side effects from dutasteride/tamsulosin. 

You should take dutasteride/tamsulosin about 30 minutes after the same meal each day. 

It is unknown if drinking alcohol will affect dutasteride/tamsulosin. The risk of side effects, such as dizziness and low blood pressure, may be increased if you drink alcohol while taking dutasteride/tamsulosin.

Does dutasteride/tamsulosin interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking dutasteride/tamsulosin.

  • A medicine for high blood pressure
  • A medicine in the same drug class as tamsulosin (an alpha blocker), such as doxazosin (Cardura) or prazosin (Minipress) 
  • A type of medicine called a phosphodiesterase-5 (PDE-5) inhibitor, such as sildenafil (Viagra, Revatio, and others), tadalafil (Cialis and others), or vardenafil (Levitra, Staxyn), which are used for erectile dysfunction or pulmonary arterial hypertension
  • Cimetidine (Tagamet HB), which is a medicine used for heartburn
  • Ciprofloxacin (Cipro), which is a medicine used for bacterial infections
  • Erythromycin (Ery-Tab and others), which is a medicine used for bacterial infections
  • Ketoconazole, which is a medicine used for fungal infections
  • Paroxetine (Paxil), which is a medicine used for depression, anxiety, or other mental health conditions
  • Ritonavir, which is a medicine used for viral infections
  • Terbinafine, which is a medicine used for fungal infections
  • Warfarin (Jantoven), which is a blood thinner medicine for blood clots

Some other medicines may alter the blood levels of dutasteride/tamsulosin. Tell your healthcare provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with dutasteride/tamsulosin. Always check with your healthcare provider.

Does Dutasteride/Tamsulosin (Jalyn) interact with other drugs you are taking?
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Overdose/Missed Dose

What should I do if I accidentally take too much dutasteride/tamsulosin?

If you or someone else has taken too much dutasteride/tamsulosin, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of dutasteride/tamsulosin?

If you miss a dose, take it as soon as you can, 30 minutes after a meal. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

If you miss dutasteride/tamsulosin for several days, call your healthcare provider for advice.

Drug Survey

Are you currently using Dutasteride/Tamsulosin (Jalyn)?

This survey is being conducted by the WebMD marketing sciences department.