Free Principles of Pharmacology MCQs with Answers

• A. Chemical name
• B. Generic name
• C. Brand name
• D. Code name

Explanation: The generic name is the accepted nonproprietary name used by health professionals and in drug references.

• A. Agonist action
• B. Antagonist action
• C. Synergistic action
• D. Potentiating action

Explanation: An antagonist binds to a receptor and blocks or reduces the action of another drug or natural substance.

• A. Increased tetracycline absorption
• B. Reduced tetracycline absorption
• C. Faster tetracycline metabolism
• D. Greater tetracycline protein binding

Explanation: Aluminium can bind with tetracycline in the gastrointestinal tract and form a poorly absorbed complex.

• A. The drug may accumulate and cause toxicity
• B. The drug will always be absorbed poorly
• C. The drug will be destroyed in the stomach
• D. The drug will have no therapeutic effect

Explanation: Reduced renal function can slow drug excretion, causing accumulation and toxicity.

• A. Immediate-release tablet
• B. Sustained-release tablet
• C. Chewable tablet
• D. Oral powder

Explanation: Sustained-release tablets are designed to release medicine gradually over time and should generally be swallowed whole.

• A. Assess for the desired effect and toxicity
• B. Give extra doses when symptoms continue
• C. Stop monitoring after the first dose
• D. Assume the usual dose is safe for everyone

Explanation: Drugs with a narrow therapeutic range require careful assessment for both treatment response and toxic effects.

• A. Rifampicin can reduce contraceptive effectiveness
• B. The contraceptive will increase rifampicin toxicity
• C. The two medicines always improve each other's action
• D. Rifampicin prevents all menstrual side effects

Explanation: Rifampicin induces hepatic drug-metabolising enzymes and can reduce the effectiveness of combined oral contraceptives.

• A. Oral route
• B. Intravenous route
• C. Rectal route
• D. Enteral tube route

Explanation: An intravenous drug enters the bloodstream directly, so gastrointestinal absorption is avoided and the full administered dose is…

• A. Therapeutic effect
• B. Expected adverse effect
• C. Idiosyncratic reaction
• D. Drug withdrawal effect

Explanation: A predictable, unwanted response occurring at a usual dose is an adverse effect.

• A. To identify possible drug interactions
• B. To ensure every drug has the same action
• C. To prevent all expected side effects
• D. To make the patient dependent on treatment

Explanation: Medication review helps identify interactions that may increase toxicity, reduce effectiveness or change drug levels.

• A. Penicillin produced by a mould
• B. Digoxin obtained from foxglove leaves
• C. Morphine obtained from opium poppy
• D. Atropine obtained from belladonna leaves

Explanation: Penicillin was originally obtained from the mould Penicillium and acts against susceptible bacteria.

• A. Absorption
• B. Distribution
• C. Metabolism
• D. Excretion

Explanation: Distribution is the movement of a drug from the blood into tissues and body fluids.

• A. Receptor agonist
• B. Receptor antagonist
• C. Enzyme inhibitor
• D. Drug antagonist

Explanation: An agonist binds to a receptor and activates a response similar to the natural substance.

• A. Increased central nervous system depression
• B. Reduced sedation from the benzodiazepine
• C. Increased urine output and thirst
• D. Improved alertness and coordination

Explanation: Alcohol and benzodiazepines can have additive depressant effects, causing excessive sedation, respiratory depression and impaired…

• A. Administer it with food
• B. Hold the dose and contact the prescriber
• C. Give half the dose and observe
• D. Ask the patient to take it later

Explanation: A documented severe allergy is a safety reason to withhold the medicine and promptly contact the prescriber for an alternative order.

• A. Idiosyncratic reaction
• B. Therapeutic effect
• C. Cumulative effect
• D. Withdrawal reaction

Explanation: An idiosyncratic reaction is an uncommon, unpredictable response that differs from the expected drug effect.

• A. Apply it to intact, dry skin as prescribed
• B. Place it over a reddened open area
• C. Cut the patch to adjust the dose
• D. Cover it with a heating pad for absorption

Explanation: Transdermal patches should be applied to clean, dry, intact skin according to the prescription.

• A. Crush the tablet without checking
• B. Ask the patient to swallow it with less water
• C. Check whether another suitable formulation is available
• D. Hide the tablet in food without explanation

Explanation: The nurse should check whether the medicine is available as a liquid or another safe formulation and clarify the order if needed.

• A. Pain relief after an analgesic
• B. Reduced blood pressure after an antihypertensive
• C. Severe confusion after a sedative
• D. Lower fever after an antipyretic

Explanation: Severe confusion after a sedative may indicate excessive or toxic central nervous system depression and requires assessment.

• A. Use the medicine if its colour looks normal
• B. Ask another patient whether it is familiar
• C. Do not use it and obtain a clearly labelled replacement
• D. Administer it and document the unclear label

Explanation: A medicine with an unreadable label or uncertain expiry must not be administered because its identity and safety cannot be verified.