Medical Knowledge Pharmacology 3

Question 1

What is the therapeutic index of a drug?

Accepted Answer

Ratio of toxic dose to effective dose

Answer

The therapeutic index is the ratio of the toxic dose (TD50) to the effective dose (ED50), measuring a drug's safety margin.

Question 2

Which oral anticoagulant requires regular INR monitoring?

Accepted Answer

Warfarin

Answer

Warfarin inhibits vitamin K-dependent clotting factors and has a narrow therapeutic range requiring frequent INR monitoring.

Question 3

What is the mechanism of action of ACE inhibitors?

Accepted Answer

Inhibit angiotensin-converting enzyme

Answer

ACE inhibitors prevent conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone-driven fluid retention.

Question 4

Which type of drug reaction involves immune system activation and is not dose-dependent?

Accepted Answer

Allergic reaction

Answer

Allergic drug reactions involve immunological mechanisms such as IgE-mediated hypersensitivity and can occur with even tiny amounts of the drug.

Question 5

What does 'QD' mean in prescription writing?

Accepted Answer

Once daily

Answer

QD (quaque die) is a Latin abbreviation meaning once daily, used in medication orders.

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