What characteristic is often associated with receptor agonists?

Receptor agonists are substances that bind to a specific receptor and activate it, leading to a biological response that mimics the action of a naturally occurring substance. One key characteristic of receptor agonists is that at higher concentrations, they can indeed lead to adverse effects. This is due to the fact that agonists can overly stimulate receptors, resulting in exaggerated physiological responses or toxic effects.

For instance, in the case of a receptor that, when stimulated, causes vasodilation, an excessive concentration of an agonist could lead to hypotension due to excessive vasodilation. Thus, higher concentrations of receptor agonists can produce a range of unwanted and potentially harmful side effects as the receptors become overstimulated, illustrating why this characteristic is significant in pharmacological practice.

The other characteristics do not accurately reflect the nature of receptor agonists. For example, while the potential for adverse effects exists (as indicated), receptor agonists do not inherently lead to drug resistance, decrease drug efficacy, or necessarily have a slow onset of action, making the focus on how higher concentrations impact therapeutic use particularly important in understanding their profile.