Staphylococcus aureus is part of the normal flora of the skin and the nose of many healthy people. It's usually responsible for minor skin infections. But occasionally, certain strains of Staphylococcus aureus may invade the lungs, bones, bloodstream, urinary tract or heart and cause life-threatening conditions. Staphylococcus aureus infections are commonly treated with antibiotics. However, these bacteria are very adaptable, and many strains have developed resistance to several antibiotics.
Penicillin Derivatives
Penicillin was one of the first antibiotics used to treat Staphylococcus aureus infections. However, as reported by MayoClinic.com, fewer than 10 percent of strains today are susceptible to it. Hence, derivatives of penicillin, such as amoxicillin-clavulanate and ampicillin-sublactam, are more commonly used. According to the Johns Hopkins Point of Care Information Center, these derivatives demonstrate good activity against methicillin-sensitive strains of Staphylococcus aureus and are especially useful to treat skin infections.
These antibiotics may be prescribed in oral or ointment form. Common side effects include diarrhea, upset stomach, vomiting and mild skin rash.
Cefazolin
Cefazolin is a first-generation cephalosporin used to treat invasive Staphylococcus aureus infections of the blood and heart. However, the Johns Hopkins Point of Care Information Center says cefazolin can't penetrate well into the cerebro-spinal fluid and therefore is ineffective against central nervous system infections.
Due to the severity of the condition, the antibiotic is usually administered intravenously. The drug's side effects are diarrhea, vomiting, itching and hives.
Clindamycin
Clindamycin is a good choice to treat a variety of Staphylococcus aureus infections, such as those of skin and soft tissue. It can also be used in combination with vancomycin or penicillins to treat toxic shock syndrome, a life-threatening condition characterized by rapid onset of high fever, vomiting, and low blood pressure.
Clindamycin is administered orally. Common side effects include nausea, vomiting, joint pain or heartburn. Pubmed Health warns that clindamycin may cause a life-threatening condition called colitis, which is inflammation of the large intestine. It should be used only to treat serious infections that can't be treated by other antibiotics.
Trimethoprim/Sulfamethoxazole
TMP/SMX is a combination of two antibiotics--trimethoprim and sulfamethoxazole--and can be used to treat non-life-threatening infections caused by methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus. However, the Johns Hopkins Point of Care Information Center recommends against the use of this antibiotic to treat blood or heart infections.
TMP/SMX is available in tablet and liquid form. It's taken orally with food for two to four times daily. Common side effects include upset stomach, vomiting and loss of appetite.
Vancomycin
Vancomycin is used to treat Staphylococcus aureus infections, especially those that are caused by methicillin-resistant Staphylococcus aureus, or MRSA. Ohio State University recommends vancomycin over TMP-SMX to treat mild staphylococcal infections. However, vancomycin resistance is on the rise, and the Johns Hopkins Point of Care Information Center recommends using it only for MRSA or for those with severe penicillin allergies.
Vancomycin is usually administered intravenously and common side effects involve the digestive tract, hives and skin rash.
