Benign prostatic hyperplasia (BPH) is the medical term for an enlarged prostate. It only affects men. The prostate is a gland that surrounds the urethra (the tube that carries urine from the bladder out through the penis). Men with BPH struggle with the frequent urge to urinate, especially at night; as well as having trouble to start urinating.
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We’ve previously written an article on BPH here.
Today, we would like to introduce to you one of the ‘bread and butter’ of BPH treatment: alpha-1 adrenergic blocker.
What’s alpha-1 adrenergic blocker?
Alpha-1 adrenergic blockers refer to a group of medications that block a type of receptor called alpha-1 adrenergic, which can be found in blood vessels, urinary bladder, eyes and many more. Alpha-1 adrenergic blockers are the primary treatment for BPH. These groups of medications help to relax the smooth muscle of the prostate, making it easier to urinate. They also relax blood vessels, causing a decrease in blood pressure.
Not all alpha-1 blockers are created equally
Since alpha-1 adrenergic blocker is an umbrella term referring to a group of medications, they should all behave similarly, right?
As a matter of fact, alpha-1 adrenergic blockers come in different generations:
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First generation (the oldest version of alpha-1 adrenergic blocker): prazosin (Minipress®)
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Second generation (the ‘middle child’): doxazosin (Cardura®), terazosin (Hytrin®)
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Third generation (the latest version): alfuzosin (Xatral®), tamsulosin (Harnal OCAS®)
Three generations differ in terms of their action on the prostate muscle (called ‘uroselectivity’) and in relation to that, their side effect. It is found that newer generations of alpha-1 adrenergic blockers, such as alfuzosin, terazosin and doxazosin are better than prazosin at reducing BPH symptoms, because their actions are more specific towards the prostate. For example, alfuzosin is better than other older kinds of alpha-1 adrenergic blockers in treating BPH and gives lesser side effects. On the other hand, prazosin from the earlier generation tend to act more 'loosely', with moderate action on the prostate and has more profound effect on blood pressure than its newer counterparts.
Doxazosin or tamsulosin are sometimes used for short-term in patients who do not have BPH (such as female patients). They are used to prepare the patients for medical expulsive therapy (MET) that remove kidney stones!
Be careful of dizziness
One of the most significant side effects of alpha-1 adrenergic blockers is dizziness. This is due to a condition known as postural hypotension.
To put it simply, alpha-1 adrenergic blockers, especially the older version such as prazosin, can reduce blood pressure drastically. As a result, patients would often feel dizzy when they try to rise up from bed or stand up from a chair. The effect can be especially prominent for people first time taking an alpha-1 adrenergic blocker (known as the first dose effect) or among frail elderly.
To better manage this side effect, patients are advised to take their first dose at night. The next morning, move slowly when rising up from bed or upon standing up from a sitting/squatting position.
But it is also due to this blood pressure-lowering effect that alpha-1 adrenergic blockers are sometimes used as treatment for high blood pressure, even though they are not always the primary choice.
Other side effects
In some cases, patients may also experience fast heart rate (called tachycardia). This may be due to the heart trying to compensate for the drop in blood pressure by beating faster. Another side effect associated with this group of medication is nasal congestion, which is due to the dilation of blood vessels in the nose. If you’re taking an alpha-1 adrenergic blocker and are experiencing these side effects persistently, consult your doctor to review your treatment.
A word from DOC2US
If you have any questions related to BPH medications, you can consult our professional doctors and healthcare professionals on DOC2US. DOC2US is a mobile application that allows you to talk to a doctor or any healthcare professionals via text chat at any time and from anywhere. For better communication, you can even send our online doctor images or voice messages related to your medical inquiry.
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