Adverse Effects of Drugs Cannot be Ignored ?
All drugs are potentially dangerous. They may cause different types of undesirable reactions.These reactions may be classified as predictable and unpredictable.The important issue that side effects happen to patients, not doctors, and we need to take them a bit more seriously.
The research shows that stimulating the molecule CD28 on cells that mediate the immune response, known as T cells, can have an adverse effect if these immune cells have been activated and altered by infection or illness in the past.
A. Predictable adverse effects:
Acute toxicity or poisoning effects of a drug occurs when it is given in an overdose.It may cause characteristic signs and symptoms and even may cause severe nervous depression and respiratory and cardiovascular failure and death.
2. Chronic toxicity:
It may also occur from repeated administration of drugs in therapeutic doses for a long time. Chronic toxicity disturbs the functions of the organs like liver, kidney, skin, GI.tract,nervous system, bone marrow and endocrine glands etc.
The measure of acute toxicity of a drug may be determined by the estimation of therapeutic index of the drug. The lower the index the greater is the chance to cause acute toxicity. The chronic toxicity is observed by giving the therapeutic dose in the animal for 96 days.
The drug most commonly used to arrest preterm labor, magnesium sulfate, is more likely than another common treatment to cause mild to serious side effects in pregnant women, according to a study from researchers at Lucile Packard Children's Hospital and Stanford University School of Medicine. Their findings suggest that, since the effectiveness of the two drugs appears similar, physicians should consider side effects more strongly when choosing which drug to prescribe.
Magnesium sulfate has some particularly unpleasant side effects, including vomiting, lethargy and blurry vision. The alternative treatment, nifedipine, often leaves women feeling better, they found.
3. Side effects:
These are the known and expected pharmacological actions of the drug in the different systems which are associated with the desired therapeutic effects of the drugs even in the usual dose. When atropine is given for the treatment of peptic ulcer in the stomach, patients are to bear the other actions of atropine in different systems such as dimness of vision,dryness of mouth, tachycardia,dysuria, etc. Ganglion blocking and alpha blocking drugs produce postural hypotension as side effects when they are used for hypertension.
The Food and Drug Administration issued a safety alert saying, "Patients who are taking Avandia, especially those who are known to have underlying heart disease or who are at high risk of heart attack, should talk to their doctor about this new information.Furthermore, data suggest that the drug might worsen complications of the disease such as weight gain, swelling, bone fractures and heart disease.
"The benefit-risk ratio of rosiglitazone therapy in type 2 diabetes mellitus needs urgent clarification," say the authors of the latest review, led by Bernd Richter, M.D., of Heinrich-Heine University. "New safety data ... should lead to a very cautious approach to rosiglitazone use. If possible, other antidiabetic medications should be employed."
These are the mild toxic or undesired effects seen with some drugs even in therapeutic doses.Aspirin in therapeutic doses causes gastric irritation, even painless gastric bleeding, nausea, vomiting, heart burn, ringing in the ear,blurring of vision, headache, dizziness etc. as untoward effects.
Medications prescribed as treatments for mood disorders can result in dry mouth (xerostomia), an increased rate of dental caries and periodontal (gum) disease. Many patients who are taking antidepressants will have dry mouth.In an effort to curtail any tooth decay, we stress with patients the importance of maintaining an extremely high level of oral hygiene care by brushing, flossing and daily fluoride therapy.
In a report published in the online issue of Circulation: Journal of the American Heart Association, (May 24, 2005), researchers said the cholesterol-lowering drug rosuvastatin (Crestor) was more likely to be associated with muscle damage (myopathy) compared to atorvastatin (Lipitor), simvastatin (Zorcor) and pravastatin (Pravachol). Adverse events were rare and occurred in the first weeks of therapy. The side effects generally go away when the patient stops taking the drug.
B. Unpredictable adverse effects:
These reactions, some times occur within therapeutic doses, unexpectedly in certain patients from time to time. These are idiosyncrasy, hypersensitivity, drug allergy etc. which have already been described.
A new drug dosing system controlled by light has been developed by scientists at Queen’s University Belfast. The devices consist of medications combined with certain chemical compounds that respond to light in ways that release precisely controlled amounts of the drug. Drug release begins when light falls on the compounds, and lasts only as long as the light continues to shine.
The system could allow the long-sought ability to deliver drugs where, when, and in the exact doses, required. This would maximize their effect and reduce side effects and damage to healthy parts of the body.Side effects among the drugs varied, causing many patients to have to try more than one before settling on long-term therapy.