#Adverse Drug Reactions #Clinical Trials

Adverse Drug Reactions Dose-related adverse drug reactions represent an exaggeration of the drug's therapeutic effects. For example, a person taking a drug to reduce high blood pressure may feel dizzy or light-headed if the drug reduces blood pressure too much. A person with diabetes may develop weakness, sweating, nausea, and palpitations if insulin or an oral antidiabetic drug reduces the blood sugar level too much. This type of adverse drug reaction is usually predictable but sometimes unavoidable. It may occur if a drug dose is too high (overdose reaction), if the person is unusually sensitive to the drug, or if another drug slows the metabolism of the first drug and thus increases its level in the blood (see Drug Interactions).Dose-related reactions are usually not serious but are relatively common.Allergic drug reactions are not dose-related but require prior exposure to a drug. Allergic reactions develop when the body's immune system develops an inappropriate reaction to a drug (sometimes referred to as sensitization). After a person is sensitized, later exposures to the drug produce one of several different types of allergic reaction. Sometimesdoctors do skin tests to help predict allergic drug reactions.Idiosyncratic adverse drug reactions result from mechanisms that are not currently understood. This type of adverse drug reaction is largely unpredictable. Examples of such adverse drug reactions include rashes, jaundice, anemia, a decrease in the white blood cell count, kidney damage, and nerve injury that may impair vision or hearing. These reactionsend to be more serious but typically occur in a very small number of people. Affected people may have genetic differencesin the way their body metabolizes or responds to drugs.Some adverse drug reactions are not related to the drug's therapeutic effect but are usually predictable, because themechanisms involved are largely understood. For example, stomach irritation and bleeding often occur in people whoregularly use aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). The reason is that these drugs reduce theproduction of prostaglandins, which help protect the digestive tract from stomach acid.Another drug the person is taking (drug-drug interaction)Food, beverages, or supplements the person is consuming (drug-nutrient interaction)Another disease the person has (drug-disease interaction)The effects of drug interactions are usually unwanted and sometimes harmful. Interactions may

Increase the actions of one or more drugs, resulting in side effects or toxicity
Decrease the actions of one or more drugs, resulting in failed treatment
Drug-Drug Interactions
Drug-drug interactions can involve prescription or nonprescription (over-the-counter) drugs. Types of drug-drug interactions include duplication, opposition (antagonism), and alteration of what the body does to one or both drugs.

Duplication
When two drugs with the same effect are taken, their side effects may be intensified. Duplication may occur when people inadvertently take two drugs (often at least one is an over-the-counter drug) that have the same active ingredient. For example, people may take a cold remedy and a sleep aid, both of which contain diphenhydramine, or a cold remedy and a pain reliever, both of which contain acetaminophen. This type of duplication is particularly likely with the use of drugs that contain multiple ingredients or that are sold under brand names (thus appearing to be different but actually containing the same ingredients).

Awareness of drug ingredients is important, as is checking each new drug to avoid duplication. For example, many prescription-strength pain relievers contain an opioid plus acetaminophen. People taking such a product who do not know its ingredients might take over-the-counter acetaminophen for extra relief, risking toxicity.

Similar problems with duplication can arise when two different drugs with the same effect are taken. This is most likely to occur when people see several doctors, obtain prescriptions at more than one pharmacy, or both. Doctors who are not aware of what others have prescribed may inadvertently prescribe similar drugs. For example, excessive sedation and dizziness can occur when two doctors both prescribe a sleep aid or when one prescribes a sleep aid and the other prescribes another drug (such as an antianxiety drug) that has similar sedative effects.

People can reduce the risk of this kind of duplication by keeping each doctor informed about all drugs being taken and by using one pharmacy to obtain all prescriptions. It is helpful to keep an up-to-date written list of all drugs being taken and to bring the list along on each doctor visit. Also, people should not take previously prescribed drugs (such as a sleeping pill or pain reliever) without checking with the doctor or pharmacist because that drug may duplicate or otherwise interact with one of their current

Видео #Adverse Drug Reactions #Clinical Trials канала Dushyanth Reddy