Staph and strep are common names for two types of bacteria that cause different types of infections in humans. Both types of bacteria typically inhabit the skin and nasal passages and occasionally cause disease. There are several factors that determine which antibiotics to choose for dealing with these bacteria.
Penicillin can be used for the treatment of strep ear infections and strep throat. Some skin strep infections can be treated with penicillin, but increasingly these bacteria have become resistant to its effect. Penicillin works by interfering with the cell wall synthesis of susceptible bacteria.
Cephalosporins are related to penicillin, but are less susceptible to the action of enzymes that inactivate penicillin antibiotics. There are four generations of cephalosporins, with the first two exhibiting greater activity against staph and strep. They are used for skin infections, as well as pneumonia and meningitis caused by strep. Cephalosporins do not work well against MRSA.
Bactrim is a sulfa antibiotic used in the treatment of skin infections caused by MRSA. It can work on some strep infections, but resistance to this antibiotic has grown within the strep bacteria. Sulfa antibiotics like Bactrim work by interfering with the growth of bacteria.
Vancomycin is a broad spectrum antibiotic used to treat severe infections caused by strep and staph. It works by inhibiting the production of materials for the bacteria’s cell wall, making it more permeable and unstable. Vancomycin is used for treatment of MRSA abscess and for complicated pneumonia and meningitis caused by both strep and staph.
Macrolides are an alternative for the treatment of strep infections in patients who are allergic to penicillin. Macrolides, like azithromycin, work by interfering with the production of proteins within the bacterial cytoplasm. Azithromycin is most commonly used in the treatment of strep throat.