Penicillin is an antibiotic used to treat a variety of bacterial infections. It works by interfering with the formation of bacterial cell walls, which kills the bacteria and stops the infection from spreading

. Common bacterial infections treated by penicillin include:

• Respiratory tract infections such as strep throat, pneumonia, and sinus infections

• Ear infections

• Skin and soft tissue infections, including staphylococcal and streptococcal infections

• Dental infections

• Urinary tract infections (UTIs)

• Certain sexually transmitted infections like uncomplicated gonorrhea

• Blood infections (sepsis), meningitis, and endocarditis caused by susceptible bacteria

• Prevention and treatment of rheumatic fever and chorea, which are complications of untreated strep throat or scarlet fever

Penicillin is effective mainly against gram-positive bacteria such as streptococci and some staphylococci, as well as certain gram-negative cocci and anaerobes. Different types of penicillin (e.g., penicillin V, penicillin G, amoxicillin, ampicillin) vary in their spectrum of activity and bacterial targets

. It is important to note that penicillin does not treat viral infections such as the common cold or flu

. Also, some bacteria have developed resistance to penicillin, so it is only effective against susceptible bacterial strains

. In summary, penicillin treats a broad range of bacterial infections primarily involving the respiratory tract, skin, ears, urinary tract, and certain systemic infections caused by susceptible bacteria