According to a survey by the Centers for Disease Control and Prevention (CDC) conducted in 2008, at that time almost 50% of Americans had used at least one prescription drug in the past month.1 A higher percentage of Americans, however, had used over-the-counter medications and dietary and herbal supplements at least once in that time frame. Pharmacology provides the studies to determine the safety and effectiveness of these medications.
Studies of Side Effects and Effectiveness in Different Populations
While the safety of medications is important for everyone, certain groups are at particular risk of adverse reactions. Researchers are studying the reasons behind drug reactions and looking for ways to personalize treatment according to people’s genetic make-up. Among the groups at greater risk for medication problems are the following:
Seniors often take multiple medications that may interact with each other and lessen the effects of the drugs or, worse, cause serious harm.2 Pharmacology and pharmacogenetics investigate how these drugs interact with each other in the body to help health care providers choose the right medication and the right dosage for patients.3 For more information on medication use and seniors, visit the NIH National Institute on Aging's Senior Health page on medication safety.
According to the CDC, one-half of pregnant women take up to four medications daily.4 Many medications may be given to pregnant women to manage their health conditions or to help the fetus develop. However, very few medications and supplements have been tested on pregnant women to determine the effectiveness and safety of these agents. A lack of testing can be harmful, however, as certain medications, for example, medications to treat acne5 and some dietary and herbal supplements6 can cause preterm labor or severe problems in fetal development or long-term development of the infant.
Infants and Children
According to the U.S. Food and Drug Administration (FDA), most drugs prescribed for children have not been tested on that age group. Until the early 2000s, only about 20% of drugs approved by the FDA were labeled for use in children.7 Health care providers often had to prescribe medication for children without the benefit of research and government regulations to back up their dosages and prescriptions. Because of this, children were often given a smaller dose of a medication for adults. Since 2002, as a result of the Best Pharmaceuticals for Children Act, the NICHD has been identifying drugs and supporting studies that contribute to pediatric labeling and improved medication safety and effectiveness in children.
For more information on the new labeling for children's medications visit the FDA's website for parents.
Certain Races and Ethnicities
Particular drugs can have different effects in different groups of people. It is important that health care providers consider their patients’ racial and ethnic backgrounds when prescribing drugs. Here are a few examples of different effects of drugs based on race/ethnicity:
- A cholesterol-lowering drug called rosuvastatin (Crestor®) has much more powerful effects in Asians than in other groups. One-half the standard dose seems to effectively lower cholesterol levels in Asians, and full doses can increase their risk of heart damage.8
- Whites are more likely than Asians to have abnormally low levels of an enzyme called cytochrome p450 2D6, which is important for metabolizing different drugs. Having low levels of the enzyme can put people at risk for accidental overdoses of medications.9
- African Americans tend to respond poorly to several classes of blood pressure medicines, including beta-blockers, ACE inhibitors, and angiotensin II agonists.9
Research to Improve Drug Safety Testing
Research is also under way to find better and faster ways to test drugs for safety and effectiveness. For example, NIH scientists are working with researchers in the Department of Defense and the FDA to develop “tissue chips,” miniature systems made with living human cells and tissues. In the future, the tissue chips might provide a way to reduce animal testing, make sure that the results of drug tests reflect the drugs’ actions in human beings, and get new drugs approved more quickly.
Participating in Drug Safety Testing
By taking part in a clinical trial, you might be able to assist with learning more about a new drug and whether it is better than those that already exist.
A clinical trial is a biomedical or behavioral research study of human subjects that is designed to answer specific questions about biomedical or behavioral interventions (such as drugs; treatments; devices; or new ways of using known drugs, treatments, or devices). Learn more about clinical trials, including definitions of clinical trials, outcomes of clinical trials, and how to get more information.
Each clinical study has its own criteria for who can participate. These are called eligibility criteria or inclusion criteria. These might be based on age, sex, health status or type of disease, medical history, and other factors. Some studies are open only to participants with certain health conditions, and others recruit healthy volunteers.10 Doctors and other health care providers run the clinical trials according to strict rules set by the FDA and other organizations to make sure that the trials are done safely and ethically.10
You can find out about clinical trials that you might be eligible for by speaking with your health care provider or by checking online at www.clinicaltrials.gov.