Nuzyra (omadacycline) is an antibiotic approved to treat two types of infections in adults: community-acquired bacterial pneumonia and acute bacterial skin and skin structure infections. It belongs to the tetracycline class of antibiotics but was designed to work against bacteria that have become resistant to older tetracyclines, including MRSA.
Community-Acquired Bacterial Pneumonia
Nuzyra’s first approved use is for pneumonia picked up outside of a hospital setting. It covers many of the most common causes of bacterial pneumonia, including the bacteria behind typical pneumonia as well as “atypical” organisms like Legionella, Mycoplasma, and Chlamydia species. This broad coverage means it can be started before doctors know exactly which bacterium is responsible, since it handles both categories.
In a phase 3 trial comparing Nuzyra to moxifloxacin (a widely used fluoroquinolone antibiotic) in 670 patients with community-acquired pneumonia, Nuzyra performed just as well. Early clinical response rates were 89.6% for Nuzyra versus 87.7% for moxifloxacin, and success rates remained consistently high across different bacterial causes, ranging from about 74% to 100% depending on the specific pathogen.
Acute Bacterial Skin Infections
The second approved use is for serious skin and soft tissue infections. These include conditions like cellulitis, wound infections, and major abscesses that require prescription antibiotics rather than simple drainage alone. Nuzyra is effective against both methicillin-susceptible and methicillin-resistant Staphylococcus aureus (MRSA), which is significant because MRSA is one of the most common and difficult-to-treat causes of skin infections.
It also covers several streptococcal species, Enterococcus faecalis, and some gram-negative bacteria involved in skin infections. This makes it a useful option when a skin infection could involve multiple types of bacteria or when MRSA is suspected.
Why It Matters for Resistant Bacteria
Older tetracyclines like doxycycline lose effectiveness when bacteria develop pumps that push the drug out of their cells or proteins that protect their internal machinery from the antibiotic. Nuzyra was engineered to overcome both of these resistance mechanisms. It binds to the same bacterial target as older tetracyclines, blocking the machinery bacteria use to build proteins, but it does so with higher potency and in a way that resistant bacteria can’t easily evade.
Beyond MRSA, Nuzyra shows activity against penicillin-resistant and multidrug-resistant Streptococcus pneumoniae, vancomycin-resistant Enterococcus (VRE), and several gram-negative bacteria. It does not, however, work against Pseudomonas, Proteus, Providencia, or Morganella species. The IDSA’s 2024 guidance on resistant infections also notes that Nuzyra is not recommended for certain highly resistant gram-negative infections like those caused by carbapenem-resistant bacteria, where its potency falls short compared to other options.
How Nuzyra Is Taken
Nuzyra comes in both intravenous and oral forms. This is a practical advantage: treatment can start through an IV in the hospital and then switch to tablets once a patient is well enough, avoiding the need for a completely different antibiotic at discharge. It is taken once daily after the initial loading period.
The oral tablets come with strict timing rules around food. You need to fast for at least 4 hours before taking the tablet with water, then avoid all food and drinks (other than water) for 2 hours afterward. Dairy products, antacids, and multivitamins should be avoided for 4 hours after a dose because they interfere with absorption. These restrictions can be inconvenient, but skipping them can significantly reduce how much of the drug your body absorbs.
Common Side Effects
Nausea and vomiting are the most frequently reported side effects, particularly with the oral form. For many people, these symptoms ease as the body adjusts over the first few days of treatment. Because Nuzyra is a tetracycline, it carries the same class-wide precautions as other drugs in this family: it can increase sun sensitivity, may affect developing teeth and bones in children (which is why it’s approved only for adults), and should not be used during pregnancy.
What Nuzyra Is Not Used For
Nuzyra is specifically approved for community-acquired pneumonia and skin infections. It is not indicated for hospital-acquired pneumonia, urinary tract infections, or bloodstream infections. While it shows lab activity against a range of bacteria beyond its approved uses, clinical data to support those uses is limited. It is also not a first-line treatment for highly resistant gram-negative infections, despite being a newer antibiotic. Its strength lies in covering resistant gram-positive organisms and atypical respiratory pathogens, filling a niche where older antibiotics may fall short.