What does a larger therapeutic index indicate?

A larger therapeutic index indicates a greater safety margin for a drug, which means there is a wider range between the effective dose and the toxic dose. This characteristic implies that there is more difficulty in reaching toxic levels of the drug, making it safer for patients. A drug with a large therapeutic index can be administered with less risk of adverse effects, as there is a lower chance of the dose approaching levels that could lead to toxicity. Therefore, options suggesting better efficacy in combating disease, stronger efficiency, or reduced side effects do not sufficiently capture the primary significance of a large therapeutic index, which focuses specifically on the safety and risk of toxicity associated with the medication.