Naoflow 0.4 mg or Cardura for BPH: Side Effects With Low Blood Pressure

Hello,

Your concern about blood pressure is reasonable. Several medicines used for benign prostatic hyperplasia (BPH) can affect blood pressure, but the risk depends on the exact drug.

Before comparing the two options, however, I would first correct an important problem with the original question: the medicine called “Naoflow” cannot be safely identified from that spelling alone.

First Confirm What “Naoflow 0.4 mg” Actually Contains

Brand names vary between countries and manufacturers, and similar-sounding names can represent completely different medicines.

A 0.4 mg capsule is a common dose and dosage form for tamsulosin, which is widely used for BPH. However, that does not prove that your medicine is tamsulosin.

For that reason, I would not assume that “Naoflow” is a 5-alpha-reductase inhibitor simply because it is being prescribed for BPH.

What Is Cardura?

Cardura is the brand name for doxazosin. Doxazosin belongs to the alpha-1 blocker group.

Alpha blockers relax smooth muscle in the prostate and bladder neck. This can reduce resistance to urine flow and improve symptoms such as:

• a weak urinary stream;
• difficulty starting urination;
• interrupted flow;
• a feeling of incomplete emptying; and
• some other lower urinary tract symptoms associated with BPH.

Doxazosin can improve symptoms, but it does not substantially shrink the prostate.

You can read more about the differences between drug classes in my guide to BPH medications.

Why Can Cardura Lower Blood Pressure?

Alpha-1 receptors are found not only around the prostate and bladder outlet but also in blood vessels. Blocking these receptors can cause blood vessels to relax, which can lower blood pressure.

This is particularly important when doxazosin is first started or when its dose is increased.

Possible symptoms include:

• dizziness;
• light-headedness;
• weakness;
• feeling faint when standing up; and
• occasionally syncope (fainting).

What Should You Do If You Are Starting Doxazosin?

Follow the dose and timing prescribed by your doctor. When first starting treatment or after a dose increase, be particularly cautious about postural dizziness.

Practical precautions include:

• rise slowly from bed or from a chair;
• sit or lie down if you feel faint or markedly dizzy;
• avoid driving or hazardous activities if the medicine is making you dizzy;
• avoid becoming dehydrated;
• tell your doctor about other medicines that also lower blood pressure; and
• contact your doctor if dizziness, weakness, fainting or very low blood pressure becomes a problem.

Is Fainting From an Alpha Blocker Harmless?

No. Fainting should not be described as harmless.

Syncope can lead to falls, head injury or other trauma, especially in older adults. If you faint after starting a medicine, or develop severe persistent dizziness or weakness, you should contact your healthcare professional promptly.

If “Naoflow” Is Actually Tamsulosin 0.4 mg

If the package confirms that the active ingredient is tamsulosin hydrochloride 0.4 mg, it is also an alpha-1 blocker used to improve BPH urinary symptoms.

Tamsulosin is more selective for alpha receptors in the prostate and urinary tract than doxazosin, so its effect on systemic blood pressure is generally less pronounced. However, it can still cause postural hypotension, dizziness and occasionally syncope.

Other Tamsulosin Side Effects to Know About

If your 0.4 mg capsule is confirmed to be tamsulosin, possible adverse effects include:

• dizziness;
• postural hypotension;
• headache in some patients;
• nasal symptoms;
• changes in ejaculation; and
• rare allergic reactions.

Tamsulosin is also associated with intraoperative floppy iris syndrome during cataract surgery. If you currently take or previously took tamsulosin or another alpha blocker, tell your ophthalmologist before cataract surgery.

What About 5-Alpha-Reductase Inhibitors?

These are a different BPH drug class and include medicines such as finasteride and dutasteride.

They reduce conversion of testosterone to dihydrotestosterone (DHT), rather than simply “reducing testosterone.” In men with an appropriately enlarged prostate, they can gradually reduce prostate volume and reduce the risk of BPH progression over time.

They work much more slowly than alpha blockers and may cause sexual side effects such as reduced libido, erectile dysfunction or ejaculatory changes in some men.

They are not interchangeable with tamsulosin or doxazosin, and the decision to use one depends partly on prostate size and the patient’s risk of progression.

Which Medicine Is Better if Your Blood Pressure Runs Low?

This cannot be decided safely from the brand names alone. Your doctor should consider:

• your actual seated and standing blood pressure;
• how low it normally runs;
• whether you already experience dizziness or fainting;
• other blood-pressure-lowering medicines;
• the severity of your BPH symptoms;
• prostate size;
• post-void residual urine and urine flow when relevant; and
• your other medical conditions.

If “Naoflow” proves to be tamsulosin, its greater urinary-tract selectivity may be relevant in someone worried about low blood pressure, but that decision should still be made by the prescribing clinician who knows your blood pressure and medication history.

Do Not Take Both Unless Your Doctor Specifically Says To

When Should You Seek Medical Advice Quickly?