Antitubercular Drugs – Transcript-Derived Study Notes

Isoniazid

  • IUPAC NAME: pyridine-4-carbohydrazide
  • USE: Isoniazid is used to treat tuberculosis (TB) or prevent its return (reactivation).

Para Aminosalicylic Acid

  • IUPAC NAME: 4-Aminosalicylic acid
  • USE: Aminosalicylic acid is known as an antituberculosis antibiotic. It works by stopping or slowing the growth of bacteria. This antibiotic treats only bacterial infections.

Pyrazinamide

  • IUPAC NAME: pyrazine-2-carboxamide
  • USE: Pyrazinamide kills or stops the growth of certain bacteria that cause tuberculosis (TB).

Ethambutol

  • IUPAC NAME: (2S)-2-[2-[[(2S)-1-hydroxybutan-2-yl]amino]ethylamino]butan-1-ol
  • USE: Ethambutol is used to treat tuberculosis (TB). It is used with other medicines for TB.

Thioacetazone (Thiacetazone)

  • IUPAC NAME: N-[4-[(Carbamothioylhydrazinylidene) methyl]phenyl]acetamide
  • USE: Thiacetazone is used to cure tuberculosis. The drug is an antibiotic medication that helps in slowing the growth of bacteria responsible for tuberculosis.

Streptomycin

  • Origin: Streptomycin is an aminoglycoside antibiotic originally isolated from the bacteria Streptomyces griseus.
  • Significance: It is the first discovered aminoglycoside antibiotic.
  • USE: Its use is primarily treating aerobic gram-negative bacterial infections, such as brucellosis, tularemia, plague (Y. pestis), tuberculosis (in combination with isoniazid, pyrazinamide, and rifampin), and certain cases of endocarditis when combined with beta-lactam antibiotics.

Rifampicin (Rifampin)

  • Classification: Belongs to the antimicrobial class of drugs;
  • USE: Used to manage and treat diverse mycobacterial infections and gram-positive bacterial infections.
  • Activity: Rifampin exhibits antibacterial activity against a wide range of gram-positive cocci, including Mycobacteria and Clostridium difficile, and specific gram-negative organisms, including Neisseria meningitidis, N gonorrhoeae, and Hemophilus influenza.
  • Mechanism of action: Rifampin exerts bactericidal antimicrobial effects by inhibiting DNA-dependent RNA polymerase (RNAP).
  • Inhibition details: This inhibition occurs either by sterically obstructing the path of the elongating RNA at its 5′ end or by reducing the RNAP's affinity for short RNA transcripts. Rifampin uniquely targets microbial RNAP, effectively arresting ongoing RNA synthesis.
  • Notes: This activity describes the indications, mechanism of action, and contraindications of rifampin as a valuable drug for treating tuberculosis, leprosy, and methicillin-resistant Staphylococcus aureus.

Cycloserine

  • USE: Cycloserine is a broad-spectrum antibiotic used in the treatment of tuberculosis and certain urinary tract infections (UTI).
  • Origin: Antibiotic substance produced by Streptomyces garyphalus.