Pharmacology is the study of drugs and their effects. The NICHD and other institutes of the NIH help conduct the research that the U.S. Food and Drug Administration (FDA) uses to determine whether a medication will be approved for everyone to use. The NICHD conducts and supports research on various medications that affect children and women, primarily to help ensure their safety and usefulness for preventing, treating, and managing various diseases and disorders.
Medical or Scientific Name(s)
Pharmacology: Condition Information
What is pharmacology?
From helping cure a headache to lowering blood pressure to prevent heart disease, medications are an important part of everyday life. Pharmacology (pronounced fahr-muh-KOL-uh-jee) is the study of these medications and how they affect the people who take them for treatment or to manage a disease or condition. The field includes the study of a variety of drugs, from over-the-counter medications and those available only with a prescription from a health care provider, to dietary and herbal supplements.
Pharmacology is tied closely to similar fields. Pharmacokinetics (pronounced fahr-muh-koh-ki-NET-iks), for example, is the study of drug absorption, distribution, metabolism, and elimination. For a medication to be effective, the appropriate amount must be given. The medication must also reach its effective target. To do this, interactions need to occur between the medication and the body. The process of pharmacodynamics (pronounced fahr-muh-koh-dahy-NAM-iks) explains how the medication affects the body.
A recent field of study, pharmacogenetics (pronounced fahr-muh-koh-juh-NET-iks), evaluates how someone’s body will respond to certain drugs based on her/his genes. A person’s genes determine the makeup of the body’s proteins. As drugs travel through the body, they interact with these proteins. Because everyone’s genes are different, even if in some cases only slightly different, each person will respond in unique ways to medications. Pharmacogenetics helps determine how much or what type of medication people will need based on their genetic makeup. This field is also called personalized medicine.1
Why is pharmacology research important?
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.
How are drugs approved for use in the United States?
The U.S. Food and Drug Administration (FDA) is the federal agency responsible for labeling medications and supplements. However, the approval process is different for prescription and for over-the-counter medications.
The FDA must regulate and approve new prescription drugs before they can be sold to the public. In 2011, the last year for which information is available, the FDA approved 35 new drugs for use by the general public.1 Although this number may seem small, the approval process for drugs is extensive.
The manufacturer or sponsor follows a series of important steps, through animal studies and clinical trials in humans, to ensure that the medication is safe, does what it claims to do, and will provide a health benefit. Testing is performed first in laboratories and on animals to determine that the drug is safe and try to understand how the drug might work in humans.
Sometimes, multiple trials are completed to measure the effectiveness of a particular medication. Participants in the studies are often followed over a period of time. For comparison purposes, some are given a placebo, an inactive or "dummy" medication, while others are given the actual drug. The NICHD and other institutes of the NIH help conduct and support the research but are not involved in the approval or labeling process.
The clinical trial phase can take years to complete. However, once research has shown that the drug is safe and useful, the FDA typically reviews and either approves or denies an application for a new drug within 6 months.
View a PDF of the FDA drug approval process. (PDF - 2.79 MB)
Over-the-Counter Drugs, Dietary and Herbal Supplements
Over-the-counter drugs and dietary and herbal supplements are not formally approved through the FDA. The active ingredients and labeling of medications and supplements in certain classes (like antacids, for example) are reviewed by the FDA to ensure that acceptable ingredients are used and that they are safe. Drug companies must conform to the requirements in the medication or supplement class, but they do not need formal FDA approval to make and sell over-the-counter medications and supplements.
The label will indicate whether a drug or supplement has been FDA approved. Talk to your health care provider about any medications you are currently taking or are considering taking to ensure that they are safe.
A generic drug is a medicine that is contains the same active pharmaceutical ingredient as a name-brand drug but is not sold under a brand name. FDA-approved generic drugs meet the same strict standards for safety, efficacy, and quality as name-brand drugs.2
Consumers usually can buy generic drugs at a much lower price than brand-name drugs. Generic versions are not available for every medicine, and in some cases may not be able to be substituted for a brand name product.
When a pharmaceutical company develops a new drug, it is protected under a patent, usually for 20 years. During this time, no other company is allowed to make or sell it. Once the patent expires, that company or another company can make and test another version of the drug. After testing and FDA approval, the company can sell the drug as a generic.3
Consumers can learn whether a generic drug is FDA-approved by using the drug approval references on the FDA website.
Pharmacology: NICHD Research Goals
Since the advent of the Best Pharmaceuticals for Children Act in 2002, the NICHD has focused on improvements in medication safety. The NICHD’s goals for research in pharmacology include:
- Testing of pharmaceuticals with appropriate audiences to ensure safe and effective treatment of disease during pregnancy, infancy, and childhood
- Identifying mechanisms of disease and molecular targets for new drug development
- Providing training opportunities for future scientists
- Promoting contraceptive research and development for preventing or reducing unintended pregnancies
- Advancing research on microbicides for the prevention of sexually transmitted diseases/sexually transmitted infections
- Evaluating the pharmacokinetics and safety of new drugs in children, pregnant women, and women who are breastfeeding, including metabolic and short- and long-term effects of exposure to these drugs
Pharmacology: Research Activities and Scientific Advances
Many organizational units within the NICHD conduct and support research in pharmacology to advance knowledge and improve treatments for various diseases and conditions within the Institute's mission.
The Obstetric and Pediatric Pharmacology and Therapeutics Branch (OPPTB) promotes research to improve the safety and effectiveness of medications for pregnant women and their fetuses and children. Recent studies include, but are not limited to, the following:
- Ibuprofen use for treatment of a congenital heart defect. NICHD researchers found that ibuprofen may be used to treat infants with patent ductus arteriosus. This heart defect occurs when the blood vessel (ductus arteriosus) that should close after birth stays open. This opening puts strain on the heart and increases blood pressure in the lungs.
- Multiple studies on the safety of medications during pregnancy include research on the use of clonidine to treat high blood pressure and the use of metformin for the treatment of diabetes.
The Pregnancy and Perinatology Branch (PPB) has recently conducted studies on:
- Prenatal steroids to improve survival rate in preterm infants. NICHD researchers found that prenatal steroids appear to boost survival and reduce brain injury in infants born as early as 23 weeks. This new finding may change the currentguidelines, which recommend these steroid hormones for infants between the 24th week and 34th week of pregnancy. These drugs improve the maturation of the lungs. Furthermore, in this study, 33% fewer deaths were reported than occurred using a comparison drug or placebo. In addition, those who survived had 20% fewer complications, from fewer cases of blindness and hearing problems to fewer developmental issues.
- New medication to reduce risk of preterm delivery. Studies conducted through the Maternaland Fetal Medicine Units (MFMU) Network resulted in approval by the Food and Drug Administration (FDA) of a new drug called 17 alpha-hydroxyprogesterone caproate (17P). A synthetic version of the hormone progesterone, this drug reduced the chance of women delivering early by about one-third. See the NICHD News Release FDA Approves Drug to Reduce Preterm Birth Risk for more information.
Researchers supported by the National Center for Medical Rehabilitation Research are studying pharmacologic therapies for patients with traumatic brain injury. Phases I and II clinical trials using single-drug therapy were unsuccessful, and researchers are now studying multiple pharmacological agents. Current studies include the combination of cyclosporine and dietary supplementation with choline and the use of vitamin D supplementation plus progesterone.
With support from the Contraceptive Discovery and Development Branch (CDDB), researchers may have discovered a compound that will lead to the creation of a nonsteroidal male birth control pill that causes nonpermanent sterility. Studies on mice were successful in inhibiting spermatogenesis and fertility using low levels of a compound that achieved male sterility in 1 to 2 weeks. The effects were reversible and removal of the compound resulted in the reversal of sterility.
Researchers in the Section on Growth and Obesity, part of the Division of Intramural Research, recently found that metformin, a diabetes drug known to decrease obesity and obesity-related comorbid conditions in adolescents, had similar effects on younger children. Children ages 6-12 years who were prescribed the medication had significant decreases in body mass index, body weight, and fat mass.
In addition, the Maternal and Pediatric Infectious Disease Branch supports a great deal of research on therapies related to reducing the spread of HIV. For example, the Branch's Therapeutic Research in HIV Infection in Infants, Children, Adolescents, and Pregnant and Non-Pregnant Women program evaluates the pharmacokinetics and safety of new medications.
To better understand drug-resistant bacteria, a serious and growing threat to public health, researchers from the NICHD’s Cell Biology and Metabolism Program studied how a small protein interacts with a cellular pump known as AcrAB-TolC complex found in the common bacterium Escherichia coli.The three components of the E. coli AcrAB-TolC complex—AcrA, AcrB, and TolC—have been studied for their roles in multidrug resistance. This complex pumps out agents, such as drugs, that threaten the survival of bacterial cells. In addition to the complex, E. coli contains about 60 small proteins that scientists have not studied as closely. The roles of these proteins are largely unknown, but because the proteins have remained stable over time and function under certain conditions, scientists think that they have important roles in the cell. Researchers conducted a study to examine small proteins and found that a certain E. coli small protein (AcrZ), which is found in the inner membrane, interacts with the AcrAB-TolC complex and plays a role in resistance to antibiotics by helping to recognize and export certain drugs out of the cell. These findings lay the foundation for future research in determining how small proteins play a role in antibiotic resistance, which could then help scientists develop improved interventions to combat bacterial drug resistance. (PMID: 23010927)
To achieve its goals related to pharmacology research, the NICHD supports a variety of programs, networks, and centers to further research and to advance training opportunities.
- The Biological Testing Facility, funded by the CDDB, is currently studying more than 150 tests and procedures for the evaluation of new drugs, formulations, and delivery systems for research in contraception and reproductive health.
- The Obstetric-Fetal Pharmacology Research Units Network, supported by the OPPTB, provides expertise and infrastructure for conducting clinical trials of medications to treat conditions in pregnancy, such as gestational diabetes, severe nausea, high blood pressure, and preterm labor.
- The CDDB-funded Contraceptive Clinical Trials Network includes 12 research sites studying contraceptive methods and devices for women, and 2 sites for men. It focuses on preventing pregnancy and on reducing the spread of sexually transmitted infections.
- The OPPTB leads the NICHD's efforts related to the Best Pharmaceuticals for Children Act, which was passed to increase research on drugs used in children. The goal of the Act and of the Branch's activities related to the Act are to improve pediatric therapeutics through preclinical and clinical drug trials that lead to changes in drug labeling.
- The Pediatric Trials Network (PTN) program , initiated in 2010 and funded by the OPPTB, is an alliance of clinical research sites located around the United States that are cooperating in the design and conduct of pediatric clinical trials to improve health care for the youngest patients.
- The Specialized Centers in Research in Pediatric Developmental Pharmacology, also funded through the OPPTB, began in 2010 with the goal of studying the safety and efficacy of medications from birth through adolescence, and providing research opportunities for scientists in this area. Currently, medications for Duchenne muscular dystrophy, pediatric cancer, retinopathy of prematurity, and bacterial infections in children are being studied.
- The PPB also supports the Maternal and Fetal Medicine Units (MFMU) Network. Established in 1986, the network focuses on clinical issues in maternal-fetal medicine and obstetrics, including maternal health, fetal health and development, gestational diabetes, asthma, thyroid disorders, and preterm labor including studies of pharmacology for treating or preventing these conditions.