Alpha-blockers are also called alpha-adrenergic antagonists. They treat various conditions like high blood pressure and benign prostatic hyperplasia (BPH). These drugs relax the muscles and help small blood vessels to remain open. They work by preventing the hormone norepinephrine (noradrenaline) from contracting the muscles in the walls of smaller arteries and veins. Blocking that effect causes the vessels to remain open and relaxed. This improves blood flow and lowers blood pressure.
What are Alpha-Blockers?
Alpha-blockers medicine is sometimes used to manage and treat essential hypertension (high blood pressure). They are not typically prescribed as the first choice of medicine for hypertensive patients and are often used alongside other medicines. Hypertension is the biggest public health concern. It is increasingly recognized as a major cause of stroke, renal problems, and cardiovascular disease. Lowering blood pressure reduces the risk of heart complications. These medicines lower blood pressure by keeping the hormone norepinephrine from tightening the muscles in the walls of smaller arteries and veins. This allows blood vessels to remain open and relaxed to enhance blood flow and lower blood pressure.
Alpha-blockers also effectively treat problems with passing urine in men who have enlargement of the prostate gland. Prostate gland enlargement is also referred to as benign prostatic hyperplasia (BPH). A patient dealing with an enlarged prostate often experience problems with urine such as a slow urinary stream, trouble starting urination, frequent urination, the urgency to urinate, waking up at night to urinate, etc. Because alpha-blockers cause relaxation of muscles throughout the body, these drugs also help improve urine flow in older men with the prostate issue.
How do Alpha-Blockers work?
Alpha-blockers are prescription drugs that affect the sympathetic nervous system and act by inhibiting the action of alpha receptors. These receptors are of two types: alpha 1 and alpha receptor 2:
• Alpha 1 receptors cause constriction of the vessels when activated by hormones produced epinephrine and norepinephrine by your adrenal glands, leading to a decrease in blood circulation and an increase in blood pressure.
• Alpha 2 receptors are present on certain nerve endings. These receptors inhibit the production of norepinephrine when activated. Norepinephrine maintains the blood flow by constriction and dilation of blood vessels.
Examples of Alpha-Blockers
Alpha-blocker medicines are either short-acting or long-acting. Short-acting drugs work quickly, but their effects last only for a few hours. On the other hand, long-acting drugs take longer to act, but their effects last longer. The alpha-blocker that suits you depends on your health and treated condition. Examples of such medicines that are used to treat high blood pressure include:
• For hypertension, once-daily preparations of doxazosin are usually recommended. The once-daily formulation is generally easier for people to take and remember the dose; Prazosin needs to be taken two to three times a day. It is associated with a large drop in blood pressure after taking the first dose.
• For treating prostate gland enlargement, once-daily preparations of Tamsulosin (Urimax 0.4 mg) or a combination of Tamsulosin and Dutasteride (Veltam Plus 0.4mg 0.5 mg) is generally recommended. Once-daily formulation causes fewer side effects than the medicines that need to be taken up to three times a day. The decision to start alpha-blocker medicines depends on how much you are bothered by the symptoms. Your doctor will help you decide what treatment is right for you.
The decision to use this drug in treatment usually depends on whether the symptoms are very much annoying or not. Alpha-blockers work by relaxing the muscles around the bladder and prostate, so that passing urine becomes easy.
What is the duration of treatment?
• Most people with high blood pressure need to take these medicines for the rest of their lives. However, in some cases, where blood pressure is adequately controlled for three years or more, medications may be stopped under a doctor’s supervision. Particularly, those who have made significant changes to lifestyle, such as having lost the extra weight, stopped smoking, or heavy drinking may achieve normal blood pressure levels. Your doctor can advise you further.
• Alpha-blockers are usually taken long term for patients with an enlarged prostate gland. Doctors usually review symptoms every 4 to 6 weeks after initiating the treatment. Once your symptoms are reduced, your treatment is usually reviewed every year. This is important to make sure the medicine is still in your system.
Taking other Medicines with Alpha-Blockers
Several drugs should usually be avoided if you have been prescribed alpha-blocker treatment. These include Sildenafil for erectile dysfunction and antidepressants such as tricyclic antidepressants, venlafaxine, or mirtazapine. When any of this medicine is combined with an alpha-blocker, you may experience a sudden drop in blood pressure.
Side Effects and Contraindications
• Alpha-blockers are frequently prescribed in the elderly male population, and toxicity is common in these individuals. The most common side effects include orthostatic hypotension, dizziness, nasal congestion, reflex tachycardia, and headache.
• Fluid retention is also a problem associated with the use of alpha-blockers. However, the side effect can be resolved by using a diuretic with the alpha-blocker.
• Alpha-blockers are ineffective in heart failure or angina patients and should not be used in these conditions.
• These drugs are contraindicated in individuals with hypersensitivity to alpha-blockers or other formulation components.
• Caution should be taken when using these drugs in elderly patients or the case of previous cataract surgery. These drugs can complicate cataract surgery by inducing sudden pupil constriction during the surgery.
Preventing the unwanted effects of medications in the elderly requires special care and communication between doctors and nurses. Alpha-blockers can have significant interactions with other medicines and have similar side effects. The administration of these medicines requires close supervision of a doctor to prevent side effects, especially in the elderly.
Alpha-blockers are generally safe when used under a doctor’s guidance. Caution should be used when starting older adults on alpha-blockers. This group has multiple risk factors that make orthostatic hypotension, a common side effect of alpha-blockers, a concern.
Your doctor will recommend the best time to take alpha-blockers. Alpha-blockers are not the first-line treatments for high blood pressure. Instead, they are prescribed in combination with other drugs, such as diuretics, when high blood pressure is hard to control. Treatment may vary from person to person; it depends on an individual’s condition and response to treatment.
Medication is the most common treatment for men with mild to moderate symptoms of prostate enlargement. In mild to moderate cases, alpha-blockers relax bladder neck muscles and muscle fibres in the prostate, making urination easier for moderate to severe cases and where medication hasn’t relieved your symptoms.
Urimax should be taken approximately half an hour following the meal every day. It is best to use this medicine exactly as advised by the doctor.
Tamsulosin, Doxazosin, Prazosin, and Alfuzosin are the common alpha blockers.