What are chemotherapy agents. The classification by its MOA. The brief description about the Sulfa drugs class and short note on co-trimaxazole.

1. CHEMOTHERPY
Prepared by: Sindhoora D
Assistant Professor
Dept.Of.Pharmacology

2. • Chemotherapy:
chemo + therapy
Chemotherapy is defined as the treatment of specific infection
with chemical agents. In the broad sense includes therapy
with antibiotics and also condition where infection is not
involved eg: maligancy
• The use of drug (chemical entity/ substance derived form
microorganisms) with selective toxicity against infections/
viruses, bacteria, protozoa, fungi and helminthes is called as
chemotherapy.

4. • This agent may be:
*Bacteriostatic
*Bactericidal

6. • Broad-spectrum antibiotics :
• are active against a wider number of bacterial types and, thus,
may be used to treat a variety of infectious diseases.
• Gram-positive and Gram-negative, or any antibiotic that acts
against a wide range of disease-causing bacteria
• Narrow-spectrum antibiotics
• are active against a select group of bacterial types.

7. SULFONAMIDES
• Sulfonamide is a functional group (a part of a molecule) that
is the basis of several groups of drugs, which are
called sulphonamides, sulfa drugs or sulpha drugs.
• Antimicrobial activity:
1. Gram positive and gram negative bacteria
2. Actinomyces and nocardia
3. Chlamydial organisms.
Resistance :
• Increased amount of PABA
• Folate synthase has low affinity
• Alternate pathway for folate metabolism

10. Pharmacokinetics:
• Absorbed in g.i.t
• Cross placenta
• Distributed all the body fluids
• Not CSF, but in meningeal inflammation high con in CSF
• Acetylation
• Excreted in urine
• Radical causes adverse effect

11. Adverse effect:
• Nausea,vomiting and epigastric pain
• Crystalluria
• Hypersensitivity rarely
• Haemopoietics toxicities agranulocytosis and
thrombocytopenia.
Uses:
• Acute bacillary dysentry
• Ulcerative colitis
• Meningococcal meningitis
• Prophylaxis of streptococcal tonsillitis

12. Cotrimaxazole
• The fixed dose of combination of trimethoprim and
sulfamethoxazole is called cotrimaxazole.
• Inhibits DHFRase enzyme.
Adverse effect:
• Nausea ,vomiting and skin rashes
• Anaemia, leucopenia and thrmobcytopenia
• Stomatitis,glossitis and crysllauria.
Uses:
• Urinary infection due to E.coli and Proteus
• Respiratory infection, gonorrhea and typhoid fever.