Oxprenolol Health Dictionary

Drugs for the relief of anxiety. They will induce sleep when given in large doses at night, and so are HYPNOTICS as well. Conversely, most hypnotics will sedate when given in divided doses during the day. Prescription of these drugs is widespread but physical and psychological DEPENDENCE occurs as well as TOLERANCE to their effects, especially among those with personality disorders or who abuse drugs and alcohol. This is particularly true of the BARBITURATES which are now limited in their use, but also applies to the BENZODIAZEPINES, the most commonly used anxiolytics and hypnotics. Withdrawal syndromes may occur if drug treatment is stopped too abruptly; hypnotic sedatives and anxiolytics should therefore not be prescribed indiscriminately, but reserved for short courses. Among the anxiolytics are the widely used benzodiazepines, the rarely used barbiturates, and the occasionally prescribed drugs such as BUSPIRONE and beta blockers like OXPRENOLOL (see BETA-ADRENOCEPTORBLOCKING DRUGS).... anxiolytics

Also called beta blockers, these drugs interrupt the transmission of neuronal messages via the body’s adrenergic receptor sites. In the HEART these are called beta1 (cardioselective) receptors. Another type – beta2 (non-cardioselective) receptors – is sited in the airways, blood vessels, and organs such as the eye, liver and pancreas. Cardioselective beta blockers act primarily on beta1 receptors, whereas non-cardioselective drugs act on both varieties, beta1 and beta2. (The neurotransmissions interrupted at the beta-receptor sites through the body by the beta blockers are initiated in the ADRENAL GLANDS: this is why these drugs are sometimes described as beta-adrenergic-blocking agents.)

They work by blocking the stimulation of beta adrenergic receptors by the neurotransmitters adrenaline and noradrenaline, which are produced at the nerve endings of that part of the SYMPATHETIC NERVOUS SYSTEM – the autonomous (involuntary) network

– which facilitates the body’s reaction to anxiety, stress and exercise – the ‘fear and ?ight’ response.

Beta1 blockers reduce the frequency and force of the heartbeat; beta2 blockers prevent vasodilation (increase in the diameter of blood vessels), thus in?uencing the patient’s blood pressure. Beta1 blockers also affect blood pressure, but the mechanism of their action is unclear. They can reduce to normal an abnormally fast heart rate so the power of the heart can be concomitantly controlled: this reduces the oxygen requirements of the heart with an advantageous knock-on e?ect on the respiratory system. These are valuable therapeutic effects in patients with ANGINA or who have had a myocardial infarction (heart attack – see HEART, DISEASES OF), or who suffer from HYPERTENSION. Beta2 blockers reduce tremors in muscles elsewhere in the body which are a feature of anxiety or the result of thyrotoxicosis (an overactive thyroid gland – see under THYROID GLAND, DISEASES OF). Noncardioselective blockers also reduce the abnormal pressure caused by the increase in the ?uid in the eyeball that characterises GLAUCOMA.

Many beta-blocking drugs are now available; minor therapeutic di?erences between them may in?uence the choice of a drug for a particular patient. Among the common drugs are:

Primarily cardioselective	Non-cardioselective
Acebutolol	Labetalol
Atenolol	Nadolol
Betaxolol	Oxprenolol
Celiprolol	Propanolol
Metoprolol	Timolol

These powerful drugs have various side-effects and should be prescribed and monitored with care. In particular, people who suffer from asthma, bronchitis or other respiratory problems may develop breathing diffculties. Long-term treatment with beta blockers should not be suddenly stopped, as this may precipitate a severe recurrence of the patient’s symptoms – including, possibly, a sharp rise in blood pressure. Gradual withdrawal of medication should mitigate untoward effects.... beta-adrenoceptor-blocking drugs

Means high BLOOD PRESSURE (raised pressure of the circulating blood), but since there is a wide range of ‘normal’ blood pressure in the population, a precise level of pressure above which an individual is deemed hypertensive is arbitrary. (A healthy young adult would be expected to have a systolic pressure of around 120 mm Hg and a diastolic of 80 mm Hg, recorded as 120/80.) Hypertension is not a disease as such but a quantitative deviation from the norm. A person with a pressure higher than the average for his or her age group is usually symptomless – although sometimes such people may develop headaches. The identi?cation of people with hypertension is important because it is a signal that they will be more likely to have a STROKE or myocardial infarct (coronary thrombosis or heart attack) than someone whose pressure is in the ‘normal’ range. Preventive steps can then be taken to lessen the likelihood of their developing these potentially life-threatening conditions.

Blood pressure is measured using two values. The systolic pressure – the greater of the two – represents the pressure when blood is pumped from the left VENTRICLE of the heart into the AORTA. The diastolic pressure is the measurement when both ventricles relax between beats. The pressures are measured in millimetres (mm) of mercury (Hg). Despite the grey area between normal and raised blood pressure, the World Health Organisation (WHO) has de?ned hypertension as a blood pressure consistently greater than 160 mm Hg (systolic) and 95 mm Hg (diastolic). Young children have readings well below these, but blood pressure rises with age and a healthy person may well live symptom free with a systolic pressure above the WHO ?gure. A useful working de?nition of hypertension is the ?gure at which the bene?ts of treating the condition outweigh the risks and costs of the treatment.

Between 10 and 20 per cent of the adult population in the UK has hypertension, with more men than women affected. Incidence is highest in the middle-aged and elderly. Because most people with hypertension are symptomless, the condition is often ?rst identi?ed during a routine medical examination, otherwise a diagnosis is usually made when complications occur. Many people’s blood pressure rises when they are anxious or after exercise, so if someone’s pressure is above normal at the ?rst testing, it should be taken again after, say, 10 minutes’ rest, by which time the reading should have settled to the person’s regular level. BP measurements should then be taken on two subsequent occasions. If the pressure is still high, the cause needs to be determined: this is done using a combination of personal and family histories (hypertension can run in families), a physical examination and investigations, including an ECG and blood tests for renal disease.

Over 90 per cent of hypertensive people have no immediately identi?able cause for their condition. They are described as having essential hypertension. In those patients with an identi?able cause, the hypertension is described as secondary. Among the causes of secondary hypertension are:

Lifestyle factors such as smoking, alcohol, stress, excessive dietary salt and obesity.

Diseases of the KIDNEYS.

Pregnancy (ECLAMPSIA).

Various ENDOCRINE disorders – for example, PHAEOCHROMOCYTOMA, CUSHING’S DISEASE, ACROMEGALY, thyrotoxicosis (see under THYROID GLAND, DISEASES OF).

COARCTATION OF THE AORTA.

Drugs – for example, oestrogen-containing oral contraceptives (see under CONTRACEPTION), ANABOLIC STEROIDS, CORTICOSTEROIDS, NON-STEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDS).

Treatment People with severe hypertension may need prompt admission to hospital for urgent investigation and treatment. Those with a mild to moderate rise in blood pressure for which no cause is identi?able should be advised to change their lifestyle: smokers should stop the habit, and those with high alcohol consumption should greatly reduce or stop their drinking. Obese people should reduce their food consumption, especially of animal fats, and take more exercise. Everyone with hypertension should follow a low-salt diet and take regular exercise. Patients should also be taught how to relax, which helps to reduce blood pressure and, if they have a stressful life, working patterns should be modi?ed if possible. If these lifestyle changes do not reduce a person’s blood pressure su?ciently, drugs to achieve this will be needed. A wide range of anti-hypertensive drugs are available on prescription.

A ?rst-line treatment is one of the THIAZIDES, e?ective at a low dosage and especially useful in the elderly. Beta blockers (see BETAADRENOCEPTOR-BLOCKING DRUGS), such as oxprenolol, acebutol or atenolol, are also ?rst-line treatments. ACE inhibitors (see ANGIOTENSIN-CONVERTING ENZYME (ACE) INHIBITORS) and CALCIUM-CHANNEL BLOCKERS can be used if the ?rst-line choices are not e?ective. The drug treatment of hypertension is complex, and sometimes various drugs or combinations of drugs have to be tried to ?nd what regimen is e?ective and suits the patient. Mild to moderate hypertension can usually be treated in general practice, but patients who do not respond or have complications will normally require specialist advice. Patients on anti-hypertensive treatments require regular monitoring, and, as treatment may be necessary for several years, particular attention should be paid to identifying sideeffects. Nevertheless, e?ective treatment of hypertension does enable affected individuals to live longer and more comfortable lives than would otherwise be the case. Older people with moderately raised blood pressure are often able to live with the condition, and treatment with anti-hypertensive drugs may produce symptoms of HYPOTENSION.

In summary, hypertension is a complex disorder, with di?erent patients responding di?erently to treatment. So the condition sometimes requires careful assessment before the most e?ective therapy for a particular individual is identi?ed, and continued monitoring of patients with the disorder is advisable.

Complications Untreated hypertension may eventually result in serious complications. People with high blood pressure have blood vessels with thickened, less ?exible walls, a narrowed LUMEN and convoluted shape. Sometimes arteries become rigid. ANEURYSM may develop and widespread ATHEROMA (fat deposits) is apparent in the arterial linings. Such changes adversely affect the blood supply to body tissues and organs and so damage their functioning. Patients suffer STROKE (haemorrhage from or thrombosis in the arteries of the BRAIN) and heart attacks (coronary thrombosis

– see HEART, DISEASES OF). Those with hypertension may suffer damage to the retina of the EYE and to the OPTIC DISC. Indeed, the diagnosis of hypertension is sometimes made during a routine eye test, when the doctor or optician notices changes in the retinal arteries or optic disc. Kidney function is often affected, with patients excreting protein and excessive salt in their urine. Occasionally someone with persistent hypertension may suffer an acceleration of damage to the blood vessels – a condition described as ‘malignant’ hypertension, and one requiring urgent hospital treatment.

Hypertension is a potentially dangerous disease because it develops into a cycle of self-perpetuating damage. Faulty blood vessels lead to high blood pressure which in turn aggravates the damage in the vessels and thus in the tissues and organs they supply with blood; this further raises the affected individual’s blood pressure and the pathological cycle continues.... hypertension

A group of drugs, also known as beta-adrenergic blocking agents, prescribed principally to treat heart and circulatory disorders such as angina and hypertension. Beta-blockers block the effects of the sympathetic nervous system, which releases adrenaline (epinephrine) and noradrenaline (norepinephrine) at nerve endings that are known as beta receptors.

There are 2 types of beta receptor: beta 1 and beta 2. Beta 1 receptors are present in the heart and blood vessels, and beta 2 in the lungs. Some betablockers (such as acebutolol, atenolol, and metoprolol) are termed cardioselective and, because they act mostly on beta 1 receptors, are used mainly to treat heart disease such as angina, hypertension, and cardiac arrhythmia. The drugs are sometimes given after a myocardial infarction (heart attack) to reduce the likelihood of further damage to the heart muscle.

Other types of beta-blocker, such as oxprenolol, propranolol, and timolol, may be given to prevent migraine attacks by acting on blood vessels in the head; reduce the physical symptoms of anxiety; or control the symptoms of thyrotoxicosis. Beta-blocker drugs such as timolol are sometimes given in the

form of eye drops to treat glaucoma and work by lowering the fluid pressure in the eyeball.

Beta-blockers may reduce an individual’s capacity for strenuous exercise. The drugs may worsen the symptoms of asthma, bronchitis, or other forms of lung disease. They may also reduce the flow of blood to the limbs, causing cold hands and feet. In addition, sleep disturbance and depression can be side effects of beta-blockers.... beta-blocker drugs

(beta-adrenergic receptor blocker) a drug that prevents stimulation of the beta *adrenoceptors at the nerve endings of the sympathetic nervous system. Blockade of ?1 receptors causes a decrease in heart rate and force; blockade of ?2 receptors causes constriction of the airways and the arteries. Beta blockers include *acebutolol, *atenolol, *bisoprolol, *oxprenolol, *propranolol, and *sotalol; they are used to control abnormal heart rhythms, to treat angina, and to reduce high blood pressure (although they are no longer regarded by some experts as the first choice of drug for treating hypertension in the absence of heart disease, being less effective than newer antihypertensive drugs). Beta blockers that block both ?1 and ?2 receptor sites cause constriction of air passages in the lungs, and these drugs should not be used in patients with asthma and bronchospasm. Other beta blockers are relatively selective for the heart (cardioselective) and are less likely to constrict the airways. Some beta blockers (e.g. *carteolol, *levobunolol, and *timolol) reduce the production of aqueous humour and therefore the pressure inside the eye; they are taken as eye drops in the treatment of *glaucoma.... beta blocker