ATENOLOL - the SIDE EFFECTS are rare albeit do exist...

SIDE EFFECTS

As with any drug, ATENOLOL is after all a xenebiotic for the body. Inherently, with the benefits of its pharmacology are its adverse side-effects. Despite the benefits, there are secondary interactions and bioactive pathways, which can lead to a diversity of implications.

On the outset, side effects from ATENOLOL are rarely observed albeit diverse in their symptoms. The following is a list of possible side effects, which may ensue whilst taking ATENOLOL.

The following is a list compiled from an actual prescription of ATENOLOL, highlighting possible adverse effects...

Tiredness
Dizzy Spells
Depression
Fatigue
Confusion
Sleep Problems
"Pins and Needles"
Sore Throat
Headache
Dry Mouth
Nausea/Vomiting
Diarrhoea
Constipation
Stomach Cramps
Fever
Hallucinations
Mouth Ulcers
Itching
Scaly Rash
Blurred Vision
Sore eyes or Conjunctivitis
Impotence
Rheumatic pain
Swelling of ankles
Temporary thinning of hair (very rare)
Peyronie's Disease
Weak pulse or mildly slow heart rate (heart block)
Coughing up blood
Blue lips/fingernails
Weakness of muscles

As demonstrated above, the array of side-effects are indeed diverse. Despite the string of possible effects stated, it has been known that the wide majority of side-effects are rarely observed, as mentioned earlier. One is unable to "rank" each side-effect in terms of their implication(s) on the patient as that is traced to their relative degrees of effect. In other words, their relative "danger" is fundamentally unique to the individual albeit some obviously posing a greater risk than others. In relation to the table above, those in red are amongst the many but very rarely observed side-effects others including sleep disturbances, depressions, paresthesiae, impotence, exanthema, psoriasis exacerbations and arthropathies. Primarily, the success of any drug is based on its ability to solve the prescribed task with the minimal implications to one's health. Essentially, this explains ATENOLOL's commercial success.

SO HOW DO THESE SIDE-EFFECTS ARISE ?

As discussed in the Biochemistry section, the nature of ATENOLOL as a potent beta-blocker antagonises the effects of adrenaline. This effectively lowers heart rate and blood pressure meaning oxygen may not be in supply at an adequate rate to organs such as the brain, essentially leading to dizziness, fatigue, and coldness of the fingers and toes. The lack of oxygen being supplied to muscles can therefore cause weakness as well as muscle and rheumatic pain due to the build-up of lactic acid from anaerobic respiration. The standard advice is therefore to avoid driving or operating machinery if on strong doses. In susceptible patients, particularly those with bronchial asthma, ATENOLOL may cause difficulty in breathing and aggravation of asthma, generically known as bronchospasms.

Conjunctivites is one side-effect which follows a different, adverse secondary pathway. The conjunctiva is abundant in unique mast cells, which play a pivotal role in explaining the onset of the condition whilst taking ATENOLOL. Mast cells release histamine and other preformed mediators upon stimulation. Histamine causes itching, hyperaemia, and increases vascular permeability. As discussed in the definition of mast cells, during extreme allergic or immune reactions (anaphylactic shock) they degranulate and produce histamines. Recent studies have shown that beta blockers, such as ATENOLOL can induce the degranulation of these mast cells, giving rise to the irritation to the conjunctiva (please refer to The Future for further information regarding these studies). This suggests that some blockers may possess pseudoallergic attributes that may account for some of the ocular side-effects of these drugs.

Prior in taking ATENOLOL, patients are required to indicate whether they suffer from any of the following conditions :


asthma
heart problems such as low blood pressure or sick sinus syndrome
diabetes
depression
thyroid disease
kidney disease
liver disease
any type of circulatory disease


In any of the above cases, the patient may not be administered, or you may require a dosage adjustment or special monitoring whilst in treatment.


ATENOLOL has been categorised in Pregnancy Category D by the FDA (Food and Drug Administration : USA). By virtue, ATENOLOL is known to have harmful effects on a developing baby. The use of beta-blockers during pregnancy has been associated with hypoglycaemia, dyspnoea, bradycardia, and hypotension in the newborn infant. In addition, ATENOLOL may pass into breast milk. Implications such as slow heart rates, low birth weight, bradycardia, hypotension, and dyspnoea have been reported in nursing babies.

However, complications can ensue if these side-effects have been traced to ATENOLOL. It is not merely a case of suddenly stopping the course of prescription. Alternative drugs must be considered, with the patient slowly being transferred to them. It has been known that some people have suffered from chest pain or a myocardial infarction (heart attack) if administration of ATENOLOL was stopped suddenly.

HOW ABOUT INTERACTION WITH OTHER DRUGS ?

By the inherent nature of any drug, ATENOLOL may interact with various other drugs. The main groups of concern are heart, diabeties, respiratory and gastro-digestive medication due to counter-effects which may be encountered. For example, whilst ATENOLOL inhibits the adrenaline pathway thereby reducing blood pressure levels, an NSAID drug such as Ibuprofen has been suggested to increase blood pressure. This counter-effect is fundamentally hazardous to the patient. Each trade name is given in brackets :

heart medication such as nifedipine (Procardia, Adalat), reserpine (Serpasil), verapamil (Calan, Verelan, Isoptin), diltiazem (Cardizem, Dilacor XR), clonidine (Catapres), digoxin (Lanoxin), doxazosin (Cardura), guanadrel (Hylorel), prazosin (Minipress), or terazosin (Hytrin).
diabetes medication such as insulin, glyburide (Micronase, Glynase, Diabeta), glipizide (Glucotrol), chlorpropamide (Diabinese), or metformin (Glucophage).

nonsteroidal anti-inflammatory drug (NSAID) such as ibuprofen (Motrin, Advil, others), naproxen (Aleve, Anaprox, Naprosyn, others), ketoprofen (Orudis, Orudis KT, Oruvail).
respiratory medication such as albuterol (Ventolin, Proventil, Volmax, others), bitolterol (Tornalate), metaproterenol (Alupent, Metaprel), pirbuterol (Maxair), terbutaline (Brethaire, Brethine, Bricanyl), or theophylline (Theo-Dur, Theochron, Theolair).
stomach medication cimetidine (Tagamet, Tagamet HB).

In addition to the above list, "over the counter" drugs such as aspirin for example are known to thin the blood, thereby increasing the rate of blood flow through veins and arteries, essentially inducing hypertension. Some "over the counter" indigestion tablets containing calcium or aluminium hydroxide may reduce the absorption of atenolol if they are taken at the same time.

 

What lies in The Future for ATENOLOL ?


 
 

KEY QUESTIONS EXPLAINED...

Medical Definitions...

CONJUNCTIVITIES ("Pink Eye") - a condition which describes the inflammation of the conjunctiva, the delicate membrane that lines the inside of the eyelids and covers the front of the eye. Symptoms include redness, swelling, and a watery or pus-filled discharge. The upmost image below illustrates a healthy conjunctiva.

WARNING ! - The following underlying image may be found disturbing by some viewers

...to view underlying image, simply place the mouse cursor over the picture below...

The lowered layered image demonstrates an eye infected by conjunctivitis indicative by the acute redness and inflammation of the conjunctiva.

MAST CELL - a large connective tissue cell that contains histamine and heparin and serotonin which are released in allergic reactions or in response to injury or inflammation. It can also be described as a granulocyte (a leukocyte that has granules in its cytoplasm) found in connective tissues. During extreme allergic or immune reactions (anaphylactic shock) it de-granulates and produces histamines. Possible explanation of induced conjunctivites. The image below shows a microscopic look at the mast cell.

PEYRONIE'S DISEASE - a disfigurement condition of the male reproductive organ.

DIABETES ("Diabetes Mellitus") - a disorder of the islets of Langerhans in the pancreas prevents the body producing the hormone insulin, so that sugars cannot be used properly.
Treatment is by strict dietary control and oral or injected insulin, depending on the type of diabetes.
There are two forms of diabetes: Type 1, or insulin-dependent diabetes, which usually begins in childhood (early onset) and is an autoimmune condition; and Type 2, or noninsulin-dependent diabetes, which occurs in later life (late onset).

HYPOTENSION - a condition which describes low blood pressure or a sudden drop in blood pressure. A person rising quickly from a sitting or reclining position may have a sudden fall in blood pressure, causing dizziness or fainting.

DYSPNOEA - medical term which describes difficult or labored respiration. Symptom is a shortness of breath disproportionate to effort. It is mostly caused by circulatory or respiratory diseases.

BRADYCARDIA - a condition that describes an abnormally slow heart rate. In healthy adults, the normal resting heart rate is about 70-80 beats per minute (athletes often have resting heart rates in the 60s and sometimes lower). In newborn babies, the normal heart rate is 120-160 beats per minute. The condition falls under the ARRHYTHMIAS syndrome category.

ARRHYTHMIAS - describes the change in the regular beat of the heart. The heart may seem to skip a beat or beat irregularly or very fast or very slowly.

FDA PREGNANCY CATEGORY D DRUGS (such as ATENOLOL) - adequate well-controlled or observational, in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy may outweigh the potential risk.

NSAID (nonsteroidal anti-inflammatory drug) - an anti-inflammatory drug that does not contain steroids. NSAID's such as ibuprofen actively inhibit the activity of both Cox-1 and Cox-2 enzymes.

SIDE-EFFECTS - R & D

As briefly mentioned in the Physical and Synthesis section, recent studies have shown that the S-ATENOLOL isomer was found to avoid the occasional side effect of an excessively lowered heart rate sometimes encountered with the racemate.

These studies are continuous and are still being conducted. Essentially, as with any other drug, Research & Developement (R & D) is the key to unveiling of the various properties of ATENOLOL.

The following section explores The Future of ATENOLOL both in terms of its expanding application in medicine and its vital R & D.

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Copyright 2004 Ravi Bhandari. All rights reserved.