What is the primary indication for using daptomycin?

Daptomycin is primarily indicated for the treatment of skin and soft tissue infections, particularly those caused by methicillin-resistant Staphylococcus aureus (MRSA). This antibiotic is effective against Gram-positive bacteria, including MRSA, and is especially useful for complicated skin and skin structure infections.

The choice of daptomycin is supported by its mechanism of action, which disrupts bacterial membrane potential leading to cell death, providing a potent option for treating resistant strains that may not respond to other antibiotics. Its use in these infections is due to its targeted efficacy against MRSA and its ability to penetrate tissues effectively.

The other options are not appropriate for daptomycin. It is not indicated for Gram-negative infections due to its lack of activity against these organisms. While daptomycin can be used in specific cases of pneumonia caused by Staphylococcus aureus, it is not the primary indication, and traditional antibiotics would generally be preferable. Additionally, daptomycin is not used for urinary tract infections, particularly because of its poor penetration in the urinary tract and lack of efficacy against the commonly involved pathogens in those infections, which are often Gram-negative.