Posology, the science of dosage, is a critical subject for ensuring patient safety and therapeutic efficacy. For B.Pharm students, a firm grasp of the factors influencing drug dosage is essential for professional practice. This quiz covers the definition of posology, the various patient- and drug-related factors that affect dosage, and the specific formulas used for pediatric dose calculations, all of which are fundamental to the responsible provision of pharmaceutical care.
- Posology is the branch of pharmacy that deals with the science of:
- Drug formulation
- Drug dosage
- Drug discovery
- Drug distribution
- Which of the following is a primary factor affecting the dose of a drug?
- The color of the drug
- The age of the patient
- The cost of the drug
- The shape of the container
- Pediatric dose calculation formulas are necessary because children:
- Are more resistant to all drugs
- Have immature hepatic and renal functions
- Always require a larger dose than adults
- Do not absorb drugs orally
- Young’s Rule for calculating a child’s dose is based on the child’s:
- Weight in kg
- Age in months
- Age in years
- Body surface area
- Clark’s Rule uses which of the following patient parameters to calculate the dose?
- Age in years
- Body weight in pounds (lb)
- Body surface area in m²
- Height in cm
- The most accurate method for calculating drug doses in children, especially for potent drugs, is the:
- Young’s Rule
- Clark’s Rule
- Dilling’s Rule
- Body Surface Area (BSA) method
- The presence of a pathological state, such as kidney or liver disease, generally requires a(n) ______ in drug dosage.
- increase
- decrease
- doubling
- stabilization
- The term “tolerance” describes a condition where:
- A patient has an allergic reaction to a drug.
- A patient requires increasingly larger doses of a drug to achieve the same effect.
- A drug has an unusually strong effect at a small dose.
- A drug has no effect on the patient.
- The route of administration that typically requires the largest dose to achieve the same therapeutic effect is:
- Intravenous
- Intramuscular
- Subcutaneous
- Oral
- Administering a drug with food can sometimes decrease the rate of absorption. This is an example of which factor affecting posology?
- Time of administration
- Route of administration
- Pathological state
- Age
- The formula: (Age in years / 20) × Adult Dose, is known as:
- Clark’s Rule
- Young’s Rule
- Fried’s Rule
- Dilling’s Rule
- Which of the following is a drug-related factor affecting posology?
- Patient’s sex
- Drug-drug interactions
- Patient’s body weight
- Environmental factors
- Women may sometimes react differently to drugs than men. This factor is related to:
- Age
- Sex
- Race
- Body surface area
- Fried’s Rule for calculating an infant’s dose is based on the infant’s:
- Weight in kg
- Age in months
- Age in weeks
- Body surface area
- The term for an unusual drug response that is different from its characteristic pharmacological effect is:
- Tolerance
- Tachyphylaxis
- Idiosyncrasy
- Synergism
- When two drugs with the same effect are administered together and produce an effect equal to the sum of their individual effects, it is called:
- Potentiation
- Antagonism
- Addition
- Synergism
- Which patient population often requires dose reduction due to a general decline in organ function?
- Neonates
- Adolescents
- Adults
- Geriatrics
- The formula: (Weight in lb / 150) × Adult Dose, is:
- Young’s Rule
- Dilling’s Rule
- Clark’s Rule
- Fried’s Rule
- The time a drug is administered can be important. For example, sedative drugs are best given:
- In the morning
- With meals
- At bedtime
- Before meals
- A psychological factor where a patient experiences a therapeutic benefit from an inert substance is known as the:
- Placebo effect
- Tolerance effect
- Idiosyncrasy
- Antagonism
- Genetic factors that cause a varied response to a drug among different individuals or populations are studied under:
- Posology
- Pharmacogenetics
- Pharmacokinetics
- Toxicology
- When the action of one drug is increased by another drug that does not have that action itself, the phenomenon is called:
- Addition
- Synergism
- Potentiation
- Antagonism
- The formula: (Age in years / (Age in years + 12)) × Adult Dose, is known as:
- Clark’s Rule
- Dilling’s Rule
- Fried’s Rule
- Young’s Rule
- A larger initial dose given to rapidly achieve a therapeutic drug concentration in the body is called a:
- Maintenance dose
- Test dose
- Loading dose
- Lethal dose
- Rapid development of tolerance to a drug after only a few doses is termed:
- Idiosyncrasy
- Allergy
- Tachyphylaxis
- Synergism
- The dose required to keep the drug concentration at a steady therapeutic state is the:
- Loading dose
- Toxic dose
- Maintenance dose
- Minimum dose
- The presence of food in the stomach generally ______ the absorption of acidic drugs like aspirin.
- increases
- decreases
- has no effect on
- inactivates
- Which of the following represents an age group with a unique posology consideration?
- Pediatrics
- Geriatrics
- Neonates
- All of the above
- The formula: (Age in months / 150) × Adult Dose, is:
- Dilling’s Rule
- Clark’s Rule
- Young’s Rule
- Fried’s Rule
- When two drugs are given together and the effect is greater than the sum of their individual effects, this is known as:
- Addition
- Potentiation
- Synergism
- Antagonism
- Why is body weight a crucial factor in determining the dose?
- It directly relates to blood volume and drug distribution.
- It determines the patient’s age.
- It affects the route of administration.
- It changes the drug’s chemical structure.
- A drug that is administered intravenously will have ______ bioavailability compared to the oral route.
- lower
- higher
- equal
- variable
- The dose of a drug is often expressed in:
- Milligrams per kilogram of body weight (mg/kg)
- Liters per hour
- Moles per liter
- Grams per mole
- Emotional state can influence drug response. This is categorized as a ______ factor.
- Pathological
- Genetic
- Psychological
- Environmental
- The term that describes when one drug counteracts the effect of another drug is:
- Synergism
- Antagonism
- Addition
- Potentiation
- An obese patient may require a different dose of a fat-soluble drug compared to a lean patient of the same weight because of:
- A faster metabolism
- A different distribution of the drug in body tissues
- A higher renal clearance
- A lower protein binding
- The “therapeutic dose” is the amount of a drug required to:
- Produce toxic effects
- Produce the desired therapeutic effect without causing toxicity
- Be lethal to 50% of the population
- Be tested in clinical trials
- Which is a physical factor that can affect the action of a drug?
- The formulation of the dosage form (e.g., tablet vs. solution)
- The patient’s emotional state
- The patient’s genetic makeup
- The patient’s age
- The term ‘cumulation’ refers to the:
- Rapid excretion of a drug
- Buildup of a drug in the body due to a slower rate of elimination than absorption
- Decrease in drug effect over time
- Interaction between two drugs
- A patient with impaired renal function would likely need a ______ dose of a drug that is eliminated by the kidneys.
- higher
- lower
- standard
- loading
- The dose that causes death in 50% of test animals is known as the:
- Effective Dose (ED₅₀)
- Toxic Dose (TD₅₀)
- Lethal Dose (LD₅₀)
- Therapeutic Dose
- Environmental factors affecting posology include:
- Altitude
- Temperature
- Exposure to toxins or carcinogens
- All of the above
- A drug’s therapeutic index is a measure of its:
- Efficacy
- Potency
- Safety
- Purity
- Which is NOT a primary reason for using pediatric dose calculation rules?
- To make the medication taste better for children.
- To account for differences in body size and composition.
- To adjust for the immaturity of metabolic pathways.
- To compensate for differences in renal function.
- A patient’s diet can influence drug action, which is a factor of:
- Pathological state
- Environment
- Genetics
- Age
- What is the first consideration when determining the dose of any medication?
- The patient’s preference
- The cost of the medication
- The approved therapeutic dose for the specific indication
- The route of administration
- The study of posology helps to prevent:
- Underdosing and therapeutic failure
- Overdosing and toxicity
- Both A and B
- Drug-food interactions only
- If a drug is taken on an empty stomach, its absorption is generally:
- Slower
- Faster
- Unchanged
- Completely inhibited
- The formula (BSA of child in m² / 1.73 m²) x Adult dose is based on:
- Clark’s Rule
- Young’s Rule
- Body Surface Area
- Dilling’s Rule
- The ultimate goal of posology is to achieve a drug concentration at the site of action that is:
- As high as possible
- Within the therapeutic window
- Below the minimum effective concentration
- Equal to the toxic concentration
I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
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