Tina Barbour-Taylor; Leah Mueller (Sabato); Donna Paris; Dorie Weaver

Learning Outcomes

By the end of this section, you should be able to:

1.4.1 Discuss the impact of socioeconomic factors on pharmacology.
1.4.2 Describe how decisions are made relative to drug therapy and specific groups of clients.
1.4.3 Explain how the “silver tsunami” is impacting drug therapy.

Pharmacology and Socioeconomic Factors

Without question, medication costs have been escalating for many years. Many factors encompass total health care costs: the up-front costs of prescription drugs, visits to providers and health care institutions, morbidity and mortality, diagnostic and interventional medicine, and suboptimal medical therapy, to name only a few. Increased drug utilization and increased price factor into this increased health care cost. A larger share of health care costs has been passed on to the consumer in the form of out-of-pocket expenses as health care costs have risen. The field of pharmacoeconomics probes into the analysis of the costs of drug therapy to health care systems and society as a whole, and it examines the consequences of providing pharmacological products and services to clients.

The prevalence of chronic conditions in the United States continues to rise and accounts for the majority of health care costs (Wilder et al., 2021). Although there are many medications that can treat these conditions, half of all clients do not take their medications as prescribed. A lack of insurance coverage does impact the likelihood of medication non-adherence. So, not only do more chronic medical conditions occur in individuals living in reduced circumstances, but those same circumstances prevent them from managing their care appropriately. The United States has a system of voluntary insurance that does not guarantee the same coverage for all individuals in the country. This is because coverage is expensive and sometimes difficult to purchase. A primary objective of the Affordable Care Act, which was signed into law under President Barack Obama in 2010, was to make it easier for people in the United States to obtain voluntary insurance. Even though it is thought that approximately 92% of individuals in the United States have some type of health coverage, over 27 million individuals are still without coverage (Statista, 2023; Tolbert et al., 2022).

Often an insurance company or a medical institution will have a drug formulary. This is a list of prescription drugs that are covered by that plan. The purpose of the formulary is to provide good care while using the most cost-effective medications. Not all drugs will be included on an insurance plan’s formulary, meaning the client may be responsible for the cost of specific drugs or switch to an alternative agent. Some insurance plans also have a deductible, which means that the client must pay a certain amount of money “out-of-pocket” before the insurance begins to pay for medications.

Costs are calculated based on how much it costs for a pharmaceutical product to be developed and manufactured. Medical visits, treatments, and hospitalizations might be considered a direct medical cost to the client. A direct nonmedical cost could be the cost associated with out-of-town office visits, such as food and lodging. These are costs associated with medical treatment, but they are not medical in nature. An indirect cost involves costs to the client that are associated with the loss of income or productivity because of an illness. Intangible costs are due to an illness but are difficult to measure, such as the cost of loss, pain, or suffering.

Medical outcomes also have to be measured. Is the outcome the preservation of life or a cure for the disease? Is the client able to be a productive member of society again? Should a drug company invest in a drug that will cure a rare disease but costs billions of dollars? Who pays for the treatment? Should the drug company invest in a much cheaper drug and help millions of people? That may seem like a simple answer unless you or a loved one are the ones with the rare disease.

Special Considerations

Socioeconomic Factors

There are many potential reasons for nonadherence to a drug regimen. Socioeconomic factors can prevent the client from receiving the care necessary to prevent disease or restore health. The nurse should identify and investigate barriers to any health care provider or clinic visits, treatments, or needed medication. Use simple, nonjudgmental language to discuss the client’s financial concerns. Explore whether the client has health insurance. Collaborate with other disciplines, such as pharmacy or social work, to develop a plan that best meets the client’s needs. Many pharmaceutical companies have programs to assist clients who cannot afford their medications.

Drugs as They Relate to Specific Populations

The very young and the very old are predisposed to be the most sensitive to drugs. One factor causing this is the differences in pharmacokinetics in these individuals. Pharmacokinetics is the movement of a drug through the body. It is easiest to think of it as “what the body does to the drug.” Drug absorption, distribution, metabolism, and excretion vary with age. The liver and kidneys are immature in very young clients, which significantly impacts metabolism and excretion; however, absorption and distribution of drugs are also impacted by their age and body size. Older adults also experience differences in pharmacokinetics; these are discussed in a separate section later in this chapter. Pharmacokinetics are discussed in more detail in Drug Administration.

Many drugs’ absorption, distribution, metabolism, and excretion differ among infants, children, and adults. Most drugs are either metabolized by the liver or excreted by the kidneys, and the rate and level of organ functioning vary between age groups.

Pediatric Population

Developmentally, infants and children have a much smaller body mass; therefore, accurate pediatric dosing is crucial. Pediatric dosing is sometimes calculated by milligrams per kilogram (mg/kg) of body weight or by body surface area (BSA). It is essential to be very accurate when calculating pediatric doses. Math should be double-checked to reduce the incidence of medication errors or inadvertently giving a higher-than-desired dose. The Pediatric Pharmacy Association commissioned several individuals to develop a KIDs List of drugs that identifies potentially harmful or inappropriate drugs in the pediatric population. The KIDs List includes two recommendation levels (avoid and use with caution).

Clinical Tip

Pediatric Dose

One safety measure is to give medication to pediatric clients using the smallest syringe available for a specific dose, allowing for a more precise measurement of the drug.

One of the challenges with drugs in pediatric clients is the limited testing when researching the drug. Almost all information about drugs, in general, is related to dosing in the adult client. The risk of performing research in this population and obtaining informed consent makes researching drugs a problem.

Body Size

Another factor that impacts an individual’s sensitivity to a drug is body size. The body’s response to a drug is often determined by the concentration of the drug at the site of action. The higher the concentration at the site, the stronger the response to the drug; the lower the concentration at the site, the less intense the response. A client with overweight or obesity may require a larger dose to obtain the intended effect, whereas an undernourished client may need a smaller dose. This is one reason that accurate height and weight are so important in the physician’s office or clinical setting. Many drugs are calculated by milligrams per kilogram of body weight to obtain the correct dosing for the intended therapeutic effect.

Sex

More research needs to be done regarding how biological differences between the sexes impact the use and metabolism of medication. Male versus female clients may experience a difference in symptomology with certain diseases. There is often a difference in body size, percentage of body fat, and muscle mass. These factors may impact the response to drugs and their effectiveness based on sex. There also is often a difference in how male versus female clients experience the adverse effects of the same drug. In 1977, most individuals assigned as females at birth were banned from many trials. This policy was reversed when Congress passed into law the National Institutes of Health (NIH) Revitalization Act of 1993 (FDA, 2018a). However, although inclusion has increased, the rate of inclusion has been slow, and there is not adequate knowledge about many drugs in regard to how they affect this population.

Pregnancy and Lactation

Pregnancy and lactation are other areas of medicine where researchers exercise greater caution due to the risk of adverse effects of a drug or substance on the fetus. When giving a drug to someone who is pregnant, the provider must consider both the pregnant client and the fetus. In many cases, it is safest to postpone treatment with drug therapy until after the birth of the infant. However, there are times when drug therapy is unavoidable, such as for a preexisting condition, upper respiratory or urinary tract infections, or the development of a condition such as hypertension or gestational diabetes that may necessitate treatment. In fact, according to Haas et al. (2018), approximately 97% of those who were pregnant took at least one drug during pregnancy. The benefit to the pregnant client and fetus should always be weighed against the risk of treatment. This can be very challenging in clinical practice.

Many physiological changes occur during pregnancy. Pregnancy alters the pharmacodynamics and pharmacokinetics of each drug and impacts the pregnant body’s response to the drug. The pregnant client has changes in bowel function, often slowing the time it takes for digestion. Gastric motility decreases, which causes decreased transit time, allowing more of the drug to be absorbed. This, in turn, causes the effects of the drug to be prolonged, and the client may be at an increased risk of toxicity. Cardiac output and uterine blood flow increase. The kidneys, breasts, and skin also have increased blood flow. Renal blood flow is essentially doubled during the third trimester of pregnancy. This results in an increased glomerular filtration rate that causes many drugs to clear the body much more rapidly.

The placenta allows the transmission of substances between the pregnant client and the fetus. Some drugs pass through the placenta to the fetus, though others are blocked. Several factors determine drug passage across the placenta (e.g., lipid-soluble drugs will pass more easily than those bound to proteins). The nurse should always assume that any medication taken during pregnancy can reach the fetus.

The primary concern with any drug during any pregnancy is its risk to the developing fetus. If a drug is known to cause fetal harm through embryonic or fetal development, it is said to be teratogenic. Only a few drugs have been proven to be teratogenic, and even though a drug might be a known teratogen, it does not mean that it will always cause harm to every fetus. It is also important to know that having no data on a drug’s safety does not mean that the drug may not cause harm—just that there is no proof. Even drugs that are generally considered “safe” during pregnancy may carry some risk—no drug can be considered 100% safe to use during pregnancy.

Before 2014, the FDA used an ABCDX system to classify drugs for pregnancy and fetal risk. Drugs in Category A were considered safest for the fetus during pregnancy, with each successive class increasingly more dangerous. Category X drugs were known to be harmful to the fetus. Often these categories were confusing and not helpful to providers and consumers. Many of the limitations of the system came from a lack of data from clinical trials. When there was a lack of data, many of the drugs were placed into Category C. This meant that no clinical trials had been performed in humans, and animal studies either had not been done or showed a risk of fetal harm. Drugs placed under Category C may have been given to pregnant clients for years with few adverse effects. In 2014, the FDA released the Pregnancy and Lactation Labeling Rule and provided new narrative guidance for the labeling of drugs. The rule took effect in June 2015, and all medications currently approved by the FDA should have the new labeling (FDA, 2021b).

These general guidelines should direct the nurse in caring for clients who may be pregnant or lactating:

Complete a thorough history of illnesses and diseases that might impact the client.
Complete a thorough history of all drugs (prescribed and/or recreational), herbal and dietary supplements, vitamins, and over-the-counter medications taken by the client.
Ask the client of childbearing age about signs or symptoms of possible pregnancy.
Discuss the potentially harmful effects of taking any drug during pregnancy and during lactation.
Recommend that the client avoid alcohol or smoking during pregnancy and lactation.
Inform the client that some herbal or complementary and alternative therapies may help with symptoms of pregnancy, but to discuss any treatments with a provider because not all are safe.

(For additional resources about caring for clients who may be pregnant or lactating, see this CDC website, which includes information on the NIH LactMed database.)

Genetics

One of the newest areas of research in pharmacology is pharmacogenetics. This area of pharmacology studies the response to drugs based on a client’s individual genetics, including therapeutic responses to drugs and the predisposition individuals might have to the adverse effects of a medication. With the identification of the human genome through the Human Genome Project, much fundamental information about the human body has improved the practice of medicine. This international collaborative project began in 1990 and was finally completed in 2003. However, it was not until 2022 that the Telomere-to-Telomere consortium finally announced that it had filled in the gaps from the original project and produced the first complete human genome sequence (National Institutes of Health, 2022).

We now know more about heredity and the disease process, and there is growing evidence about the influence of genetic variations on drug response. Often two clients will respond differently to the same drug. This research may help identify genetic variants in the response to drugs that may be unique to a race or ancestral group. Genetic variations can change the structure of drug receptors and target molecules, which can then influence an individual’s response to a specific drug. At some point in the near future, clients will benefit from customized drug therapy specific to their genetics. It will predict the best drug for use in a particular situation and allow the dose to be prescribed that best limits side effects or toxicity.

Special Considerations

Cultural Concerns

There are cultural considerations that the nurse must integrate into the care of the client:

Acknowledge individual differences.
Reflect on one’s own potential inherent biases.
Practice cultural humility.
Embrace and respect diversity.

Accommodating the culturally diverse:

Assess their ability to communicate.
Engage an interpreter if the client’s use of English is limited.
- Avoid using a family member to translate when possible.
Provide health information to the client and family members in their primary language, when possible.
Assess the client’s current health practices.
Determine whether cultural healers are important to the client.
Obtain a complete history of the client’s medications and use of herbals, OTCs, vitamins, and CAM.
Determine the client’s views about touch, eye contact, and modesty.
Recognize that various cultural and biological responses may occur within different groups.
- Black clients may not respond to some antihypertensive drugs (e.g., beta-adrenergic blockers and angiotensin-converting enzyme inhibitors).
- Asian clients may require a smaller dose of many medications.
Obtain a cultural history.
Consult with someone knowledgeable about the client’s cultural history and practices, but always verify beliefs with the client.
Obtain an understanding of what the client perceives as “good health.”
Inquire about their beliefs regarding health, wellness, and illness.

The Aging Client and Pharmacology

There is an increasing number of older adults around the world. One of the terms used to describe the aging population is “silver tsunami.” This somewhat negative term refers to the combination of the large number of baby boomers who are reaching retirement age, the improved life expectancy for older adults, and a reduced birth rate among younger adults. The U.S. Census Bureau projects that the nation’s 65 and older age group will grow to almost 95 million individuals by 2060 (Vespa et al., 2020). This will impact the Social Security system, and there will most likely be greater demand for health care and long-term care. There is also concern that there will be a shortage of workers in many professions across the United States, including in health care.

The aging adult presents a challenge to the health care provider as health declines. As society ages, individuals have more comorbid conditions, often leading to the use of multiple medications (Pazan & Wehling, 2021). According to the Kaiser Family Foundation (Kirzinger et al., 2019), approximately 90% of adults over the age of 65 take at least one prescription drug. They go on to report that this population also is more likely to take multiple prescriptions. Although drugs can alleviate or even cure many diseases, these same drugs can cause many drug-related problems. The nurse must be aware of these potential drug-related problems when caring for the older client.

Older adults have changes in organ function that affect their response to most drugs, from the standpoint of both pharmacokinetics and pharmacodynamics. These changes can result in an increase in sensitivity to drugs due to declining liver and kidney function. Diminished kidney function may impact the individual’s ability to filter and excrete the drug. A drug’s absorption rate may also be affected because transit time through the gut usually slows with age. Gastric acidity also decreases, which may impact absorption because some drugs require high acidity to dissolve. If the individual has diminished liver function, that may affect the metabolism of some medications, which may prolong the drug’s effects and lead to toxicity.

Often older adults are excluded from clinical trials, just as pregnant people and children have been. When compounded by the fact that many older adults regularly take multiple medications, it can have a detrimental effect on the client. Adverse drug reactions occur more frequently in the older population and frequently cause hospital admissions and readmissions. Some of the factors that cause this increase are polypharmacy (taking many drugs), treatment with drugs that have a narrow safety margin, and multiple chronic conditions. The American Geriatrics Society (AGS) publishes a reference list of drugs called the Beers Criteria® for Potentially Inappropriate Medication Use in Older Adults.

The following are some of the pharmacologic considerations when providing nursing care for an older adult:

Take a complete drug history at each encounter, including how the drug was prescribed.
- Verify that the client is taking the medication as prescribed.
Ask about new prescriptions from other providers.
Assess the older adult’s age-related sensory issues (mental awareness, hearing or visual acuity).
Ask about any history of liver or kidney problems.
Encourage the client to use aids such as a pillbox, especially if taking multiple drugs.
Check the drugs for potential interactions, especially if the client sees multiple providers.
Monitor for both expected therapeutic effects and potential adverse effects.
Ensure the client understands the purpose of each drug, expected effects, and potential adverse effects.
Review the drug list to determine if any drugs could be discontinued.
Identify any potentially inappropriate drugs (e.g., drugs that cause sedation may cause a client to fall).
Question the client about drugs they may be crushing or cutting in half. (Some capsules and extended-release pills should remain intact.)
Encourage clients to dispose of old or expired medications.
Determine whether the client can afford the drugs (especially new prescriptions).
Encourage the health care provider to order the least complicated drug regimen possible.

1.4 Special Considerations