How does Alpha-1-Adrenergic Blockers Works?

Type of Drug:

Antihypertensives; drugs used to lower high blood pressure.

How the Drug Works:

Alpha-1-adrenergic blockers dilate both veins and arteries to reduce resistance against which the blood must flow. This lowers blood pressure. Alpha-1-adrenergic blockers also relax the muscles around the urethra and improve symptoms of benign prostatic hyperplasia.

Uses:

Doxazosin, prazosin, terazosin: To treat high blood pressure alone or in combination with other blood pressure-lowering medications (eg, diuretics).

Doxazosin, tamsulosin, terazosin: For the treatment symptoms of benign prostatic hyperplasia (BPH).

Unlabeled Uses: Occasionally doctors may prescribe prazosin for treatment of benign prostatic hypertrophy.

Precautions:

Do not use in the following situations: Allergy to the drug or any of its ingredients.

Use with caution in the following situations: liver disease (doxazosin only) prostate cancer

"First dose" effect: Dizziness, fainting, and falling are possible because of lowered blood pressure, especially early in therapy. These symptoms are more likely to occur when rising quickly from a seated or lying position, if the dose is increased, if the therapy is stopped and then started again, or if more than one antihypertensive drug is being taken. To lessen the chances of problems, the first dose should be given at bedtime. Sit or lie down if you feel light-headed.

Priapism: A painful penile erection that sustains for hours Occurs rarely. Contact your doctor if you experience symptoms of this conditions.

Pregnancy: There are no adequate and well-controlled studies in pregnant women. Use only if clearly needed and potential benefits out­weigh the possible hazards to the fetus. Tamsulosin is not indicated for use in women.

Breastfeeding: Prazosin appears in breast milk. It is not known if doxazosin or terazosin appear in breast milk. Tamsulosin is not indicated for use in women. Consult your doctor before you begin breastfeeding.

Children: Safety and effectiveness in children have not been established. Tamsulosin is not indicated for use in children.

Lab Tests: Lab tests and blood pressure testing may be required to monitor treatment.

Drug Interactions:

Tell your doctor or pharmacist if you are taking or planning to take any over­the-counter or prescription medications or dietary supplements while taking this drug. Drug doses may need to be modified or a different drug prescribed. The following drugs and drug classes interact with this drug:

• Beta-adrenergic blockers (eg, propranolol) (prazosin only)

• Cimetidine (eg, Tagamet) (tamsulosin only)

• Cionidine (eg, Catapres)(prazosin only)

• Verapamil (eg, Calan) (terazosin only )

Side Effects:

Every drug is capable of producing side effects. Many patients experience no, or minor, side effects., The frequency and severity of side effects. depend on many factors Including dose duration of therapy, and Individual susceptibility. Possible side effect include:

Digestive Tract: Nausea; vomiting; stomachache; indigestion; diarrhea; constipation; gas.

Nervous System: Depression; dizziness' incoordination; feeling of whirling motion (vertigo); nervousness; anxiety; drowsiness; fatigue; sleepless; headache; abnormal skin sensations; lack of energy; fainting.

Circulatory System: Pounding in the chest (palpitations); dizziness or light­headedness when rising quickly from a sitting or lying position (orthostatic hypotension); rapid or irregular pulse; low blood pressure.

Respiratory System: Difficulty breathing' nasal congestion; sore throat; runny nose; inflamed sinuses; cold symptoms; bronchitis; increased cough; nosebleed; flu symptoms,

Skin: Rash; itching; sweating; flushing.

Other: Painful erections; sexual problems; swelling of arms and leg? (edema); facial swelling; dry mouth; ringing in the ears; weight gain; loss of bladder control; frequent urination' abnormal or blurred vision; eye pain or irritation; liver; urinary tract infections; gout; muscle cramps or. spasms; neck, back" chest, joint, muscle, to general body pain or discomfort; red eyes; Infection; weakness; tooth disorder.

Guidelines for Use:

• Dosage is individualized. Take exactly as prescribed.

• Do not stop taking or change dose, unless instructed by your doctor.

• If a dose is missed, take it as soon as possible. If several hours have passed or it is nearing time for the next dose, do not double the dose to catch up, unless instructed by your doctor. If more than one dose is missed or it is necessary to establish a new dosage schedule, con­tact your doctor or pharmacist.

• Patients being treated for high blood pressure often feel tired and run down for a few weeks after beginning therapy. It takes time for the body to adjust to lowered blood pressure. Continue taking your medication even though you may not feel quite normal. Check with your doctor or pharmacist during this time regarding any new symptoms that Occur to ensure that these new feelings are a normal consequence of changes in blood pressure.

• Take the first dose at bedtime in order to reduce the risk of dizziness and light-headedness which may Occur early in therapy. Take doxazosin, prazosin, and terazosin without regard to food. Take tamsulosin about 30 minutes after the same meal each day.

• Do not crush, chew, or open tamsulosin capsules.

• Medication will be started at a low dose and then slowly increased until maximum benefit is achieved.

• If therapy is stopped for several days, therapy should be restarted at the low dose and then slowly increased.

• May cause drowsiness, dizziness, light-headedness, or blurred vision. Use caution when driving or performing other tasks requiring alertness, coordination, or physical dexterity. Avoid engaging in any hazardous tasks for at least 12 to 24 hours after taking the first dose of these medications, missing several doses, increasing the dose, or taking other high blood pressure medications with these products. Sit or lie down if you feel light-headed.

• Dizziness or light-headedness may also Occur following alcohol ingestion, standing for long periOds of time, exercise, or during exposure to extreme heat.

• Use caution when rising from a sitting or lying position. If dizziness, light­headedness, or pounding in the chest (palpitations) become bother­some, notify your doctor.

• Stop taking and contact your doctor immediately if you experience a painful penile erection lasting for hours and not relieved by intercourse or masturbation.

• Do not take any other prescription or OTC medication or dietary supplements without first consulting your pharmacist or doctor.

• Inform your doctor if you are pregnant, become pregnant, plan on becoming pregnant, or are breastfeeding.

• Tamsulosin is not indicated for use in women or children.

• Lab tests and blood pressure testing may be required to monitor therapy. Be sure to keep appointments.

• Store at room temperature (68° to 86° F). Protect from light and moisture.