Ch 2

Drugs are "bound" to

proteins in the blood during transportation

Agonists:

receptor to Drugs that interact with a stimulate a response

Absorption rate depends on..

route, blood flow, and solubility of the drug

Many alterations in absorption can be managed by

separating the times of administration

Topical medications can be influenced by

skin thickness and hydration

Bound medication

tends to stay in tissues longer - (drug blood levels)

Many interactions that cause a change in distribution usually affect

the binding of a drug to an inactive site

Bound vs Unbound

unbound is usable portion of the mediation. Bound tends to stay in tissues longer - (drug blood levels)

Drug Interactions occur

when the action of one drug is altered or changed by the action of another drug

Liberation

• Drug released from dosage form and is dissolved in body fluid Process converting oral drug can be influenced by food and water in the stomach

Excretion

• Elimination of drug metabolites and some of the active drug from the body

Which instruction would the licensed practical nurse provide to the patient prescribed Humulin R (human) to prevent hypertrophy of subcutaneous fat tissue?

"Rotate the injection sites each time."

Half-Life of Drugs

Factors modifying the quantity of drug reaching a site of action after a single oral dose

When the nurse administers a 50-mg dose of a drug with a half-life of 6 hours, how many milligrams will remain in the body at 24 hours?

6.25 mg

Drug Interactions Elicited in the following two ways

> By agents that, when combined, increase the action of one or both drugs > By agents that, when combined, decrease the effectiveness of one or both drugs

Which patient can be treated with glucagon therapy?

A diabetic patient showing symptoms of hypoglycemia

According to the Centers for Disease Control and Prevention (CDC), which patient is prediabetic?

A patient with a fasting plasma glucose level of 100 mg/dL

Percutaneous:

Absorbed through the skin and mucous membranes

Most drug interactions that alter absorption take place in the

GI tract

- A patient reports postoperative pain, and the nurse administers morphine (a narcotic analgesic) intravenously to ease the pain. Fifteen minutes later, the nurse notes that the patient is very drowsy, respirations are slow and shallow, and oxygen saturation is low. The nurse administers another drug that decreases the action of the morphine. What is this effect called?

Antagonistic

The nurse instructs a patient prescribed exenatide (Byetta) to take the drug at which time?

At 60 minutes before morning and evening meals

Which action describes the mechanism of action of sodium-glucose cotransporter 2 (SGLT2) inhibitors?

Block the reabsorption of glucose by the kidneys

Which laboratory value does the nurse monitor in a patient taking glimepiride (Amaryl) for blood sugar control?

Blood dyscrasias may be seen in patients taking glimepiride, so it is important to monitor CBC levels.

Parenteral:

Bypasses the Gl tract by using subcutaneous, intramuscular, and intravenous injection

Drug Stage Excretion:

Depends on GI tract and kidneys - lungs, saliva, breastmilk, skin

Drug Stages > Distribution

Depends on circulation to be transported throughout body blood and lymph

Drug Stages Metabolism:

Depends on enzyme systems - disease states, age, environmental polluntants

Drug Stages > Absorption:

Depends on route of administration - oral vs. IV

Drug Stages > Liberation:

Drug released from dosage form - how it it disperses from original form

Antagonist:

Drugs that attach to a receptor but do not stimulate a response

The laboratory result of a patient taking an oral hypoglycemic agent shows an elevation in low-density lipoprotein (LDL) cholesterol levels. Which medication may be responsible?

Empagliflozin (Jardiance)

Drug receptors:

Specific sites where drugs form chemical bonds - like a lock and key

Duration of action:

How long the drug has a pharmacologic effect

• A patient is being started on a new drug that has been used safely by many people for years. The patient has no known allergies, and the nurse administers the drug correctly. Suddenly the patient experiences cardiac arrest. What is this type of reaction called?

Idiosyncratic

Which laboratory finding would concern the nurse in a patient taking a biguanide?

Increased aminotransferase levels

Percutaneous examples

Inhalation, sublingual, or topical

Which route of administration has the fastest rate of distribution?

Intravenous

the major organ of excretion;

Kidneys

LADME

Liberation Absorption Distribution Metabolism Excretion

Pharmacodynamics:

Study of interactions between drugs and their receptors and the series of events that result in a pharmacologic response

Allergic reactions:

Occur among patients who have previously been exposed to a drug and whose immune systems have developed antibodies to the drug

Idiosyncratic reactions:

Ocur when something unusual/abnormal happens when drug is first administered to patient

Unbound drugs:

Pharmacologically active portion

Metabolism

The process whereby the body inactivates drugs Primary organ of metabolism is the liver; other sites are Gl tract and lungs

Which statements are true regarding thiazolidinediones (TZDs)? Select all that apply.

They lower blood glucose levels. They inhibit hepatic gluconeogenesis. They increase the sensitivity of muscle and fat tissue to insulin.

Peak action:

Time at which the drug reaches the highest concentrations on the target receptor sites

Which adverse effect does the nurse monitor for in a patient prescribed sitagliptin (Januvia)?

Upper respiratory infection

Enteral:

Via the gastrointestinal tract by the oral, rectal, or nasogastric routes

Onset of action:

When the concentration of a drug at the site of action is sufficient to start a physiologic response

A patient starting metformin (Glucophage) normally runs 5 miles a day. Which adverse reaction is of most concern to the nurse upon hearing the patient's exercise regimen? a.Lactic acidosis b.Increased abdominal pain c.Increased hyperglycemia with exercise d.Increased low-density lipoprotein (LDL) levels

a.Lactic acidosis

Some medications can cause

binding or unbinding of another medication, increasing or decreasing its effect

Some drugs cannot pass through the..

blood- brain barrier or the placental barrier

Drugs are transported throughout the body by

body fluids to the sites of action

incompatibility reaction

chemical response of drugs mixed together resulting in inactivation or deterioration of one or both drugs

Subcutaneous and intramuscular injection absorption is affected by

circulation

Protein binding and fat solubility affect

distribution

Intravenous medications are absorbed

fastest

some medications are excreted..

in feces

unbound

is usable portion of the mediation.

Drug interactions that cause a change in excretion usually act in the

kidney tubules by changing the pH to enhance or inhibit excretion

Organs with largest blood supply receive the distributed drug...

most rapidly