N17 Practice Q's (ch 1-3)

Which FDA pregnancy category would appear to be the safest for a developing fetus?

Category A

What is the main disadvantage to the IV method of drug administration?

Once a drug is injected, it cannot be withdrawn. Miscalculation of dosage or mistakes in drug selection may cause serious consequences. Intravenous injection also requires the services of medical personnel to administer the drug. It has the risk of infection. Pain.

The study of the action of drugs on living tissue

Pharmacodynamics

The study of the use of drugs in treating disease

Pharmacotherapeutics

What is the drug microsomal metabolizing system, and what is its main function?

The drug microsomal metabolizing system is a group of enzymes mainly in the liver that break down lipid-soluble drugs into water-soluble metabolites. Function: involved in the metabolism of approx. 75% of all drugs used today

Nutritional deficiencies, particularly decreased protein intake, can

decrease drug metabolizing enzymes

Change to which pharmacokinetic process leads to longer duration of action of drugs?

decreased excretion

Select the factor that would not cause a decrease in drug metabolism in the elderly

decreased liver blood flow (?)

Drug distribution is affected with aging due to

decreased total body water

An unusual or unexpected drug reaction by an individual is known as

drug allergy

parenteral administration

drugs are given by injection into the skin, muscles, or veins

oral administration

drugs are given by mouth

The time a drug continues to produce its effect is its

duration of action

When a drug increases the rate of drug metabolism of other drugs, the process is termed

enzyme induction

Which of the following could be categorized as an adverse reaction?

idiosyncrasy, drug allergy, teratogenicity, carcinogenicity (all of the above)

Usually refers to physical alterations of drugs that occur before administration when different drugs are mixed in the same syringe or other container.

incompatibility

Why is the plasma drug concentration important?

it is the most reliable measurement of the intensity of drug action

For drugs to cross the blood-brain barrier, they must be

lipid soluable

The rate of drug absorption would be increased by which of the following?

lipid solubility

First-pass metabolism refers to the metabolism of drugs in the

liver

A medication that does not require a physician's service to obtain is referred to as

nonprescription

The time from drug administration to the first observable drug effect is known as the

onset of action

The medical situation when a particular drug should not be administered is referred to as

contraindiction

A drug that has the potential for abuse and is regulated by the Drug Enforcement Agency is classified as a

controlled substance

The drug administration route demonstrating the slowest onset of action is

transdermal

By what method of cell transport are most drugs absorbed? What are the main requirements for drug absorption?

-Drugs are primarily absorbed by passive diffusion. -Drugs possessing lipid solubility are readily absorbed. If a drug is water soluble or ionizable, the un-ionized form is required for absorption to occur.

Explain the difference between idiosyncrasy and drug allergy.

-Idiosyncrasy is an unusual or unexpected drug response. It is usually caused by genetic differences among individuals. -Drug allergy is an adverse drug reaction that occurs when an individual becomes sensitized to a drug. Antibodies produced within the body react with the drug to cause an allergic reaction

What is the difference between site of action and mechanism of action?

-Site of action is the location within the body where a drug exerts its therapeutic effect. It may be a body organ, tissue, or specific drug receptor site. -The mechanism of action refers to how the drug produces its effects. Mechanism of action may involve inhibition of a body enzyme or chemical process or may involve the drug acting as an antagonist on a receptor to block the action of a hormone or body substance

*Increased* duration and/or intensity of drug action:

-cirrhosis of liver -an increase in creatinine levels in the blood -renal disease -malnutrition -enterohepatic recycling of drugs -decrease in plasma proteins -lipid soluble drugs

Age-related physiologic changes that occur in humans include

-decreased cardiac output -decrease in organ size -decreased blood flow to the liver -fever cells to carry out organ function (all of the above)

*Decreased* duration and/or intensity of drug action:

-drugs that cause microsomal enzyme induction -drugs that increase liver blood flow

Factor(s) that reduce patient drug compliance include

-mental confusion -polypharmacy -drug side effects -drug costs (all of the above)

Explain the difference between a prescription drug, OTC drug, and a controlled substance.

-prescription drugs require a written or phone order by a licensed physician and must be dispensed by a licensed pharmacist. -OTC drugs can be sold at a variety of stores and do not require a physician or pharmacist. -controlled substances are drugs that have the potential for abuse and are scheduled and regulated by the Drug Enforcement Administration (DEA)

What is the relationship between ED50, LD50, and therapeutic index?

-the effective dose 50 (ED50) is the dose that will produce half the maximal response possible. -the lethal dose 50 (LD50) is the dose that will kill half of the animals tested during a test of drug toxicity. -the therapeutic index is the ratio of the ED 50 to the LD 50, which provides an estimate of the relative safety of a drug.

What are the major age-related changes that occur in the liver?

-volume changes -polyploidy -accumulation of dense bodies (lipofuscin) inside lover cells -decreased area of smooth endoplasmic reticulum -declining number and dysfunction of mitochondria

What are the main factors that determine plasma concentration?

1. drug distribution into the tissues 2. rate of drug metabolism 3. drug excretion (ie. drug dosage, route of admin, and bioavailability--> determines how much drug gets into the body)

Describe three changes in body composition that occur with aging.

1. loss of bone 2. loss of muscle mass and strength 3. increased body fat

List the major pathways of drug excretion.

1. renal 2. gastrointestinal

Drug X has a half-life of 6 hours. How much drug is left in the body 18 hours after an IV injection of 1200 mg?

150 mg

List the factors that can contribute to individual variation in drug response.

Age, sex, diet, race, and body weight

Explain why alkalinization of the urine increases the rate of excretion of drugs such as aspirin or phenobarbital.

Aspirin, phenobarbital, and other acidic drugs are predominantly in their ionized form in alkaline urine and therefore are readily excreted. In acidic urine, they are more un-ionized and consequently more likely to be reabsorbed into the blood.

Drugs that have demonstrated teratogenic effects in women are classified as Pregnancy Category

X

toxic effect

a harmful effect that requires a reduction in dosage or elimination of a drug

When the combined effect of two drugs, each producing the same biologic response by the *same* mechanism of action, is equal to the sum of their individual effects

additive effect

side effect

an unwanted physical or mental effect caused by a drug

When the combined effect of two drugs is *less than* the sum of their individual effects.

anatgonism

Competative antagonist

binds reversably to a receptor and increasing the concentration (dose) of the agonist can remove the antagonist from the receptor

The study of the processes of drug absorption, distribution, metabolism, and excretion

pharmacokinetics

The study of drugs

pharmacology

The science of preparing and dispensing medicines

pharmacy

Which factor of individual variation is dependent upon the patient's attitude toward treatment?

placebo effect

Select the term that relates to the amount of drug administered to produce a therapeutic effect.

posology

The study of the amount of drug that is required to produce therapeutic effects

posology

The measurement of creatinine can be used to evaluate

renal function

The main effect of aging on drug absorption is

slowing of drug absorption

agonist

stimulate the activation of receptors

When the combined effect of two drugs, each producing the same biologic response but by a *different* mechanism of action, is equal to the sum of their individual effects

summation

antagonist

suppress the activity of receptors

When the combined effect of two drugs is *greater than* the sum of their individual effects

synergism

intravenous injection

the administration of medication by injection directly into a vein (IV)

intramuscular injection

the administration of medication by injection directly into muscle tissue, at a 90 degree angle (IM)

Therapeutic effect

the desired or intended effect a medication is expected to have on the body; ie to alleviate symptoms or disease process

Briefly describe the main factors that determine drug distribution.

the more lipid soluble the drug, the greater the degree of distribution, especially into the brain, adipose tissue, and other tissues with high lipid content.

Decreased drug effects after chronic administration.

tolerance

The study of the harmful effects of drugs on living tissue

toxicology

The proprietary drug name supplied by a pharmaceutical company is also referred to as the

trade name