BMI2605
ASSIGNMENT 2 SEMESTER 1 2026
UNIQUE NO. 257221
DUE DATE: 21 APRIL 2026
, Pharmacology - BMI2605
QUESTION 1
1.1 Define the therapeutic index and explain its significance in pharmacology.
The therapeutic index (TI) is a measure of the safety of a drug and is defined as the
ratio between the toxic dose and the effective therapeutic dose of a drug. It is usually
expressed as:
TI = TD50 / ED50
Where TD50 is the dose that produces toxicity in 50% of the population and ED50 is the
dose that produces the desired therapeutic effect in 50% of the population.
The significance of the therapeutic index lies in its ability to indicate how safe a drug is
for clinical use. A drug with a large therapeutic index has a wide margin between the
effective dose and the toxic dose, making it safer to use. In contrast, drugs with a
narrow therapeutic index, such as digoxin or warfarin, require careful monitoring
because small changes in dosage can lead to toxicity. Therefore, the therapeutic index
is an important factor in determining dosage regimens and ensuring patient safety.
1.2 What is the difference between potency and efficacy in drug action?
Potency refers to the amount of drug required to produce a specific therapeutic effect.
A highly potent drug produces its effect at a lower dose compared to a less potent drug.
Efficacy, on the other hand, refers to the maximum effect that a drug can produce
regardless of dose. It represents the drug’s ability to produce the desired therapeutic
outcome.
The main difference is that potency relates to the dose required, whereas efficacy
relates to the maximum effect achievable. A drug can be highly potent but have low
ASSIGNMENT 2 SEMESTER 1 2026
UNIQUE NO. 257221
DUE DATE: 21 APRIL 2026
, Pharmacology - BMI2605
QUESTION 1
1.1 Define the therapeutic index and explain its significance in pharmacology.
The therapeutic index (TI) is a measure of the safety of a drug and is defined as the
ratio between the toxic dose and the effective therapeutic dose of a drug. It is usually
expressed as:
TI = TD50 / ED50
Where TD50 is the dose that produces toxicity in 50% of the population and ED50 is the
dose that produces the desired therapeutic effect in 50% of the population.
The significance of the therapeutic index lies in its ability to indicate how safe a drug is
for clinical use. A drug with a large therapeutic index has a wide margin between the
effective dose and the toxic dose, making it safer to use. In contrast, drugs with a
narrow therapeutic index, such as digoxin or warfarin, require careful monitoring
because small changes in dosage can lead to toxicity. Therefore, the therapeutic index
is an important factor in determining dosage regimens and ensuring patient safety.
1.2 What is the difference between potency and efficacy in drug action?
Potency refers to the amount of drug required to produce a specific therapeutic effect.
A highly potent drug produces its effect at a lower dose compared to a less potent drug.
Efficacy, on the other hand, refers to the maximum effect that a drug can produce
regardless of dose. It represents the drug’s ability to produce the desired therapeutic
outcome.
The main difference is that potency relates to the dose required, whereas efficacy
relates to the maximum effect achievable. A drug can be highly potent but have low
