DIFFERENT EFFECTS OF DRUGS

                                            

Medication effects on tissue are classified as desirable and undesirable. A desirable effect occurs when the medication improves the patient’s health. An undesirable effect occurs when the medication interferes with the patient’s normal physiology. A medication can have both a desirable and an undesirable effect. The healthcare provider determines whether the desirable effects outweigh the undesirable effects before administering the medication to the patient. Additional medication may be given to reduce the undesirable effects of another medication. A desirable effect is called the medication’s therapeutic effect and is the reason for the healthcare provider to administer the medication. An undesirable effect is called either a side effect or an adverse side effect, depending on the consequence the undesirable effect has on the patient. A side effect is an undesirable effect that is relatively not harmful to the patient, such as drowsiness caused by an antihistamine. An adverse side effect is an undesirable consequence that is harmful to the patient, such as when healthy cells are destroyed along with cancerous cells during chemotherapy.

The Placebo Effect

It is any treatment (including drugs, psychotherapy, quack therapy, and surgery) that achieves an ameliorative effect on a symptom or disease but that is in fact ineffective or is not specifically effective for the condition being treated. Many effective antianxiety drugs have been prescribed both knowingly and unknowingly at placebo dosages. Hundreds of studies have demonstrated the effectiveness of antidepressant drugs for the treatment of depression in a range of 45 to 80 percent—pretty impressive, but the placebo effectiveness in depression is also high, ranging from 30 to 50 percent. Placebos are effective for a variety of conditions. Patients with angina pectoris (insufficient blood flow to the heart) responded to placebo surgery in which surgeons made only an incision in the chest. And in a study of the drug propranolol that is used after heart attacks to prevent further damage, investigators noticed that patients who took placebo pills regularly had a lower death rate than patients who took placebos sporadically. Therefore, the placebo effect is not unique to psychiatric illness. Conversely, what types of patients are not really amenable to a placebo effect? If you are a type I (insulin-dependent) diabetic, who goes into hypoglycemic shock, a placebo effect will not help. No matter how much patient  believe in whatever he is or is not taking, nothing will change the physiological dynamics between circulating blood glucose level and brain’s extremely high need for this energy substrate.

Medication Safety

The Food and Drug Administration requires that medication undergo rigorous testing before approving the medication. Testing includes the following animal studies to determine the medication’s therapeutic index. A therapeutic index is a ratio between the median lethal dose and the median effective dose and indicates the safe dose to administer to the patient to achieve the therapeutic effect. These tests also provide scientists with information on how the medication is absorbed, distributed, metabolized, and excreted.

Acute Toxicity Study: Toxic effect usually appears within 24 hours with single or multiple exposures. This is the initial test that determines the dose that is lethal to 50% of tested laboratory animals.

Sub Acute Toxicity Study: When animal species are administered daily doses of the medication for 30 days, toxic effect appears within 30 days.

Sub Chronic Toxicity Study: Two animal species are administered daily doses of the medication for 90 days. Animal test subjects are given physical examinations and laboratory tests during the 90 days to determine the medication’s effect on organs.

Chronic Toxicity Study: Two animal species are administered three dose levels, nontoxic, therapeutic, and toxic. The medication is usually administered over the life span of the test animal or the duration that the medication is intended to be given to humans. Animals are given physical exams and laboratory tests to determine the effect of the medication on organs and its potential carcinogenicity.