α-ADRENERGIC BLOCKERS

Question 1

Action

Answer 1

α-Adrenergic blockers act by binding to α-adrenergic receptors, causing dilation of peripheral blood vessels. Lowers peripheral resistance, resulting in decreased B

Question 2

Uses

Answer 2

α-adrenergic blockers are used for benign prostatic hyperplasia, pheochromocytoma, prevention of tissue necrosis and sloughing associated with extravasation of IV vasopressors.

Question 3

Contraindications

Answer 3

Hypersensitive reactions may occur, and allergies should be identified before these products are given. Patients with MI, coronary insufficiency, angina, or other evidence of CAD should not use these products.

Question 4

Administer

Answer 4

• Starting with low dose, gradually increasing to prevent side effects
• With food or milk for GI symptoms

Question 5

Side Effects

Answer 5

The most common side effects are hypotension, tachycardia, nasal stuffiness, nausea, vomiting, and diarrhea.

Question 6

Pharmacokinetics

Answer 6

Onset, peak, and duration vary among products.

Question 7

Interactions

Answer 7

Vasoconstrictive and hypertensive effects of EPINEPHrine are antagonized by α-adrenergic blockers.

Question 8

Nursing Considerations

Answer 8

Assess:
• Electrolytes: K, Na, Cl, CO2
• Weight daily, I&O
• B/P lying, standing before starting treatment, q4hr thereafter
• Nausea, vomiting, diarrhea
• Skin turgor, dryness of mucous membranes for hydration status
Evaluate:
• Therapeutic response: decreased B/P, increased peripheral pulses
Teach patient/family:
• To avoid alcoholic beverages
• To report dizziness, palpitations, fainting
• To change position slowly or fainting may occur
• To take product exactly as prescribed
• To avoid all OTC products (cough, cold, allergy) unless directed by prescriber

Question 9

Selected Generic Names

Answer 9

α 1 blockers:
• silodosin
• tamsulosin