How does increasing selectivity affect side effects?

How does increasing selectivity affect side effects?

• A. All degrees of selectivity will produce a desired effect, but as the drug gets more selective, it will have less and less side effects
• B. More selectivity increases side effects
• C. Selectivity has no impact on side effects
• D. Side effects are only determined by dosage

Answer: (A)

Increasing selectivity means the drug interacts mainly with its intended target and avoids other receptors or pathways. Side effects often come from those off-target interactions. So, as a drug becomes more selective, it can still produce its desired therapeutic effect, but the likelihood and variety of unwanted effects drop because fewer unintended targets are being affected. Of course, side effects can still occur from on-target actions at high doses or due to tissue-specific sensitivities, but the general trend is that greater selectivity reduces adverse effects.

Increasing selectivity means the drug interacts mainly with its intended target and avoids other receptors or pathways. Side effects often come from those off-target interactions. So, as a drug becomes more selective, it can still produce its desired therapeutic effect, but the likelihood and variety of unwanted effects drop because fewer unintended targets are being affected. Of course, side effects can still occur from on-target actions at high doses or due to tissue-specific sensitivities, but the general trend is that greater selectivity reduces adverse effects.