Compare Cardura vs. Flomax

Head-to-head comparisons of medication uses, side effects, ratings, and more.



Lowers blood pressure and makes it easier to urinate. For men, Doxazosin will help make it easier to urinate so that you're not getting up a lot at night. It's a last-choice treatment for high blood pressure.Makes it easier to urinate. Flomax (Tamsulosin) is a first-choice treatment for enlarged prostate, and it's available as a generic. However, it can cause changes in your sex drive and can take a while to kick in.
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
Reviews for Cardura (Doxazosin)
of people say Cardura (Doxazosin) is worth it
say it works well
say it's a big hassle
Reviews for Flomax (Tamsulosin)
+25% vs. Cardura (Doxazosin)
+23% vs. Cardura (Doxazosin)
+3% vs. Cardura (Doxazosin)
Side effects
  • Dizziness 10%
  • Fatigue/feeling unwelle/malaise 6%
  • Fatigue 6%
  • Drowsiness 4%
  • Inflammation inside the nose 2%
  • Swelling due to excess fluid 1%
  • Vision abnormal 1%
  • Vertigo 1%
  • Sexual dysfunction 1%
  • Pain 1%
More Cardura side effects »
  • Inflammation inside the nose 10%
  • Dizziness 7%
  • Cough increased 3%
  • Infection 3%
  • Muscle weakness 3%
  • Back pain 2%
  • Sinus inflammation 2%
  • Drowsiness 2%
  • Nausea 1%
  • Tooth disorder 1%
More Flomax side effects »
How it works
Doxazosin is a selective alpha blocker. It relaxes the urethra and prostate, which makes it easier to urinate. It also lowers blood pressure by relaxing blood vessels.Flomax (Tamsulosin) is an alpha-1 blocker. It specifically targets and relaxes muscles in your prostate, which makes it easier to urinate.
Type of medication
Alpha blocker
Prescription only
Alpha blockerPrescription only
Available as
  • Pill
  • Extended release
  • Pill
Used for (click to learn more)
Risk factors for serious side effects
  • Age 65 years or older
    • Cataract surgery
    Detailed Cardura (Doxazosin) risks & warnings »
    • Taking medications for high blood pressure
      • Cataract or glaucoma surgery
      • Alcohol use
      • Heavy exercise
      • Hot weather
        Detailed Flomax (Tamsulosin) risks & warnings »
        Pregnancy category
        CFDA pregnancy category (Weigh risks vs. benefits)

        Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

        See the FDA package insert
        BFDA pregnancy category (Probably safe)

        Research studies with animals haven’t found a risk to unborn babies, but it hasn’t been properly studied in humans.

        See the FDA package insert
        No specific alcohol-related info.
        • People on Flomax (Tamsulosin) can be more likely to have heat stroke. Drink plenty of fluids if you're going to be in hot weather, especially if you're going to be exercising or drinking alcohol.
        • Take the extended release tablet with breakfast.
        • Take this 30 minutes after the same meal every day.
        Kidneys and liver
        No specific kidneys and liver-related info.No specific kidneys and liver-related info.
        • Rare reports of a painful erection unrelieved by sex have been reported by men who take Cardura (Doxazosin), which is also called priapism. Contact your doctor immediately if you develop this as impotence can happen if this isn't treated in time.
        • Can reduce sex drive.
        • Can cause changes in sex drive.
        • People on Flomax (Tamsulosin) can experience changes in their sex drive. Talk to your doctor if you find this bothers you.
        No specific sleep-related info.No specific sleep-related info.
        No specific weight-related info.No specific weight-related info.
        Upsides and benefits
        • A first-choice treatment for enlarged prostate. Makes it easier to urinate.
        • First-choice medication for relieving the symptoms of an enlarged prostate.
        • Helps make urinating easier.
        • Available as a generic medication.
        • Also available in a combination form with another medication to treat more severe symptoms of an enlarged prostate.
        • Since it works only on the muscles around the prostate, it has fewer blood pressure and heart-related side effects than other medicines in the same class.
        Downsides and risks
        • A last-choice treatment for high blood pressure because other medicines are more effective at preventing heart disease. Your doctor might add it to a medicine you're already taking if your blood pressure is still too high.
        • Has to be taken the same time every day.
        • It can take up to one month to see the full effects of the medication.
        • Can reduce sex drive.
        • Flomax (Tamsulosin) can't be stopped suddenly, so you'll need to talk to your doctor about how to stop taking it safely.
        • It doesn't shrink the size of the prostate.
        Tips from our pharmacists for people taking the medication
        • Can cause dizziness or fainting in the first few days.
        • Check your blood pressure 1 week after starting this medicine, and tell your doctor if it hasn't improved.
        • Can cause fatigue or headache.
        • Take the extended release tablet with breakfast.
        • You might need to check your blood pressure from time to time while taking this medicine.
        • If side effects don't go away, talk to your doctor about alternatives.
        • Take this 30 minutes after the same meal every day.
        • Can cause dizziness, muscle pain, headache and stuffy/runny nose.
        • Can cause changes in sex drive.
        • Don't stop taking this medication suddenly without talking to your doctor.
        Learn more
        More about CarduraSide effectsReviews & ratingsAlternativesFDA package insert
        More about FlomaxSide effectsReviews & ratingsAlternativesFDA package insert