INTRODUCTION

Beta adrenergic receptors blocking agents, commonly called beta blockers compete with B agonist for B1 or B2 receptors sites.

Beta 1 Beta 1 receptors are primarily in the heart. They

are also present at sympathetic nerve ending where they are associated with increase norepirephrine release.

In the kidney they increases rennin, in fat cells increases lipolytes.

B2 B2 receptors are present in the bronchial and vascular

smooth muscles. They are also present in Skeletal muscle where they increases potassium uptake and glycogenolysis, and in the pancreas they are associated with increases of insulin.

B1 and B2 receptors are used as antihypertensive drugs. These drugs reduce blood pressure by blocking sympathetic

effects on the heart thus decreasing the heart rate and cardiac output.

They are also decrease blood pressure by blocking adrenergic nerve mediated release of rennin.

They also reduce the peripheral vascular resistance.

DEFINITION

Beta blockers are type of drugs that effect over body response to certain nerves. Are used to control abnormal heart beat like arrhythmias and to treat Angina.

DISTRIBUTION OF BETA RECEPTORSOrgan Receptor Effect of Stimulation

Heart B1 Increased heart rate

B1 Increased cardiac contractility

B1 Acceleration of AV conduction

Bronchi B2 Dilation

Artrioles B2 Dilation

Kidney B1 Release of renine

Metabolism B1 Increased in free faty acids

Metabolism B2 Increased in blood sugar

GROUPS OF BETA BLOCKERSDrugs Route Onset of Action Peak Action Duration of Action

Propranolol (Inderal) Oral 30 mint 2 – 4 hrs 8 – 12 hrs

Metoprolol (Mepressor)Poprol x L

I/VOral

Immediate > 01 hour

2 mint1 ½ hour

15 mint13 – 19 hrs

Atenolol (Tenormin) OralI/V

1 hourmints

2 – 4 hrs20 mint

24 hours5 – 8 hrs

Nadolol(Corgard)

OralI/V

> 3 hrsimmediate

3 – 4 hrs5 mints

20 – 24 hrs7 hrs

Penbatolol(Levatol)

Oral 15 mints 1 ½ - 3 hrs 20 – 24 hrs

Timolol Maleate(Blocadren)

Oral 30 mints 1- 3 hrs 12 hrs

Pindolol(Visken)

Oral < 1 hour 1 hour 24 hrs

Acebutolol Sectral

Oral 1 hour 2 ½ - 3 ½ hrs 24 – 30 hrs

Carteolol – Hydrochloride (Catrol)

Oral < 1 hour 1 – 3 hrs 24 hrs

INDICATION They are considered as a drug of choice in obese

patient and in younger clients with hyperdynamic Circulation. B blockers are specifically recommended for the client who have experienced (i) IHD (ii) Angina (iii) MI because they reduce the risk of subsequent episode. B blockers are used cautiously to treat hypertension in clients with Asthma, Insulin dependent diabetes, peripheral vascular disease and CHF.

Use of B blockers effect B 2 adrenergic receptors that mediate bronchodilation.

ON CONTRAINDICATION

Client with chronic bronchitis asthema.

Response of beta blockers are poor in elderly patient.

Hypotension Liver toxity Avoid with use of nasal decongestion.

SIDE EFFECTS OF BETA BLOCKERS

Nausea Vomiting Liver toxity Rash Abdominal pain Jaundice Change in colour of stool

COMPLICATIONS

Cardiogenic shock. Arrthmias Unconsciousness Heart failure Heart block

ATENOLOL (TENORMIN)

Atenolol is a selective B1 receptors antagonist a drug belonging to the group of beta blockers.

A class of drug that uses primarily in cardiovascular diseases.

Excretion: Renal

Lactic: In lactiferous female

Formula: C14 H22 N2 O3

FUNCTION

Slowing down its heart and reducing its work load.

Unlike propranolol atenolol does not pass through the blood brain barriers thus avoiding various central nervous system side effects.

INDICATION

Atenolol is indicate for a number of condition include:

Hypertension Angina Acute M.I Supra ventricular tachycardia

CONTRAINDICATION

Bradycardia Cardiogenic shock Metabolic acidosis AV block second & third degree

heart block CHF

SIDE EFFECTS Indigosion, Constipation, Diziness,

Faonness, Cold Extremities, Depression. Rhinitis, Impotence, Confusion, Fatigue, Rash, Hypotension, Some Serious Side Effects May Require Urgent Treatment.

Mepressor

A beta blocker used primely to treat the hypertension and Angina pectoris

NURSING INTERVENTIONNursing Intervention Rational

1. Monitor for urinary hesilency (hypertrophic prostatic)

1. It may be a sign of decrease blood supply due to hyptension

2. Monitor for syncopy 2. Over dose of drug

3. Monitor for vital sign level of consciousness and mood

3. Adrnergic antagonist can exacerbate existing mental depression

4. Monitor for dizziness, drawsiness and headache

4. Decreased blood flow to the brain. Hypotensive.