Which of the following best describes the use of ketoconazole?

Ketoconazole is a versatile antifungal agent that can be used to treat both systemic and topical fungal infections. This broad-spectrum activity stems from its mechanism of action, which involves inhibiting the synthesis of ergosterol, a vital component of fungal cell membranes. By disrupting the integrity of the cell membrane, ketoconazole effectively kills or inhibits the growth of various fungi.

For systemic fungal infections, ketoconazole is particularly effective against conditions caused by organisms such as Candida and certain dermatophytes. Its ability to be absorbed systemically makes it useful for treating more serious fungal infections that may require oral or intravenous administration.

In terms of topical applications, ketoconazole is also available as a cream or shampoo formulation, allowing for effective treatment of superficial fungal infections like athlete's foot, ringworm, and seborrheic dermatitis. This dual capability underscores the broad range of infections that ketoconazole can address, making it a valuable agent in antifungal therapy.

Other options are limited in their scope. Some might suggest that ketoconazole is strictly for systemic fungal infections or only for topical use, but these statements do not fully capture the drug's comprehensive utility in treating a wide range of fungal infections. The assertion that ketoconazole is only for bacterial infections