Which of the following statements is true about Schedule I drugs?

Schedule I drugs are classified as substances that have a high potential for abuse and no accepted medical use in treatment in the United States. This classification indicates that they cannot be prescribed, distributed, or dispensed for medical purposes. Substances in this category include drugs such as heroin, LSD, and ecstasy, among others, which are considered to pose significant risks of addiction and other adverse effects without recognized therapeutic benefits.

In contrast, the other options present statements that do not align with the characteristics of Schedule I drugs. For instance, stating that they have accepted medical use contradicts their classification. Similarly, the option about refills is inaccurate as Schedule I substances cannot be refilled or prescribed at all. The claim that they are used to treat serious conditions is also false, as such drugs have not been recognized legally for medical treatment. Therefore, it is accurate to say that Schedule I drugs are illegal to prescribe.