Tigecycline mesylate is primarily used as an antibiotic to treat various bacterial infections. It is effective against a wide range of Gram-positive and Gram-negative bacteria, including those that are resistant to other antibiotics. This makes it particularly useful in treating complicated skin and soft tissue infections, complicated intra-abdominal infections, and community-acquired bacterial pneumonia. It is often reserved for cases where other treatments have failed or are not suitable due to resistance patterns. Additionally, it is sometimes used in hospital settings to manage infections caused by multi-drug resistant organisms, such as MRSA (Methicillin-Resistant Staphylococcus aureus). Its broad-spectrum activity and ability to combat resistant strains make it a valuable option in challenging clinical scenarios. However, it should be used with caution due to potential significant side effects, such as gastrointestinal effects and an increased risk of mortality in some cases.