Penicillin

Penicillin is a group of antibiotics which include penicillin G (intravenous use), penicillin V (oral use), and benzathine penicillin (intramuscular use). Penicillin antibiotics were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. Penicillins are still widely used today, though many types of bacteria have developed resistance following extensive use.

Penicillin was discovered in 1928 by Scottish scientist Alexander Fleming. People began using it to treat infections in 1942. There are several enhanced penicillin families which are effective against additional bacteria; these include the antistaphylococcal penicillins, aminopenicillins and the antipseudomonal penicillins. They are derived from Penicillium fungi.

Binds peptidoglycan binding protein to inhibit the cross-linking of peptidoglycan, therefore inhibiting bacterial cell wall synthesis

• gram-positive cocci

  • Streptococcus

  • Enterococcus

• gram-negative cocci

  • Neisseria

• Treponema pallidum (syphilis)

Hypersensitivity reactions

Hemolytic anemia

Cleavage of the beta-lactam ring by enzymes known as beta-lactamases found in bacteria.