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Which bacterial infections can penicillins treat?
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Penicillins are a class of antibiotics used to treat a wide range of bacterial infections by inhibiting the synthesis of bacterial cell walls. Their specific clinical application depends on the type of penicillin used:12
- Naturally occurring penicillins: These remain the drugs of choice for treating streptococcal sore throat, tonsillitis, syphilis, meningitis, and endocarditis caused by certain streptococci.12
- Broad-spectrum penicillins: Developed to treat infections caused by gram-negative rods, these are effective against urinary tract infections as well as typhoid and enteric fevers.1
- Extended-spectrum agents: These possess greater activity against gram-negative bacteria, including Pseudomonas aeruginosa, which often causes serious infections in individuals with weakened immune systems.1
While penicillins were historically effective against Staphylococcus, many strains have developed resistance, leading to the emergence of methicillin-resistant Staphylococcus aureus (MRSA), which these agents cannot effectively treat.12