Which term indicates the strength of a medication in producing effects?

• A. Efficacy
• B. Bioavailability
• C. Safety
• D. Potency

Answer: (D)

Potency describes how much drug is needed to produce a given effect. A more potent medication achieves the same effect at a smaller dose than a less potent one, which is why it’s said to be more potent. This is about the dose required to reach a particular response, not the maximum effect the drug can produce. Efficacy, by contrast, is the greatest effect a drug can achieve, regardless of dose. Bioavailability is about how much of the administered dose actually reaches the bloodstream, and safety concerns the risk of adverse effects. So, when asked about the strength of a medication in producing effects, potency is the right term because it focuses on the dose needed to elicit a response. For example, if Drug A relieves pain at 5 mg and Drug B requires 50 mg for the same relief, Drug A is more potent.