Bpt Chemotherapy

Dr.U.P.Rathnakar MD.DIH.PGDHM

Chemotherapy -General  Definitions  Classification

 Problems from the use of AMAs  Combined use of AMAs  Prophylactic use of AMAs

Chemotherapy-Definitions

• Chemotherapy -Treatment of infectious

•

• • • • •

diseases using chemical substances – (chemo: chemical agents, therapy: treatment) Antibiotic -Substance obtained from microorganisms and acts against microorganisms AntiMicrobial Agent -Synthetic substances act against microorganisms. Bacteriocidal- Kills microorganisms Bacteriostatic- Stops multiplication Broad spectrum- Act Against variety of micro organisms Narrow spectrum- Act against limited

Classification

 Bacteriocidal-Penicillin,

Cephalosporin OR  Bacteriostatic- Tetracyclines, Sulfa

Broad spectrum-

Tetracyclines OR

Classification[MOA]….

 Inhibit cell wall synthesis- Penicillin,

Cephalosporins  Affect cell membrane functionAmphoterecin B  Inhibit protein synthesisChloramphenicol, Tetracycline, Erythromycin, Aminoglycosides  Antibiotics that inhibit nucleic acid synthesis: Rifampicin, fluoroquinolones, nalidixic acid, anticancer agents, anti-HIV drugs

Problems from the use of AMA [Complications]

• Hypersensitivity[Allergy]- Urticaria [skin • • •

• •

rashes] to anaphylaxis Direct toxicity; Local- Pain. Eg. Penicillin injection or gastritis by erythromycin Systemic toxicity- Hearing impairment[oto toxicity] or affect kidneys [Nephro toxicity]- Eg.Aminoglycosides Drug resistance: AMA not effective after being initially effective Natural or acquired

Problems from the use of AMA [Complications]

• Super infection [Suprainfection]- New o o

o o •

•

infection because of use of AMAs Why? Normally Normal flora compete with pathogens for food and also produce substances called bacteriocins which inhibit microorganisms- AMAs kill these floraPredisposing conditions- Diabetes , Cortecosteroid therapy Organism-Candida Nutritional defeciencies- Intestinal flora synthsize Vit K and B complex vitamins. AMAs kill them

Combined use of AMAs  Reduces - Bacterial resistance  Increases - Efficacy and cure rate  Increases the - spectrum of activity  Reduce - duration of treatment  Reduce the toxicity  To achieve synergism

Amoxicillin

Benzathene pen

Cefazoline

Rifampicin

Zidovudine

Prophylactic use of AMAs [Chemoprophylaxis]

Co-Trimoxazole

 Cotrimoxazole is a mixture of two drugs  Trimethoprim and      

Sulphamethoxazole.[1:5] Combination increases the antibacterial activity MOAPrevent synthesis of folic acid in bacteria. Bacteriocidal Each component inhibit different enzymes[Sequential blockade] PABA[T→T]Dihydrofolate[S→S]Tetrahyd

Co-Trimoxazole…. Uses

2.Urinary tract

infections 3.Respiratory tract infections: 4.Typhoid fever 5. Bacterial dysentery

Adverse effects[Toxicity] 2. Hypersensitivity [Allergic reactions] 3. Stevens-Johnson's syndrome 4. Jaundice, 5. Hemolytic anaemia, 6. Crystalluria Contra indicationsI8. Allergic to sulphonamides. 9. Avoided during pregnancy. 10.Hepatic and Renal failure

Penicillins-[Beta lactam group]

Classification 1. Natural penicillins:

Eg.Penicillin-G, Benzathine penicillin 2. Semi synthetic penicillins: 1.Acid resistant: Eg.Penicillin V 2.Amino penicillins: Eg. Amoxycillin, Ampicillin 3.Carboxy penicillins: Carbenicillin

MOA

 Inhibits

bacterial cell wall synthesis  Bacterioci dal

Penicillins

Adverse effects[toxicity]

Uses

• Penicillin -a safe

 Tonsillitis  Meningitis

antibiotic • Hypersensitivity[Aller gy] reactionsAnaphylaxis Skin rashes • Bleeding abnormalities • Convulsions Precaution: Test dose

Natural Penicillin

 Prophylactic use-

Rheumatic fever  Typhoid fever  UTI

Semi synthetic Penicillins

Cephalosporins [Betalactam group] Classificati MOA

on  First generation

Cefazolin, cefalexin  Second generation Cefamandole,  Third generation Ceftriaxone,  Fourth generation

 Inhibits

bacterial cell wall synthesis  Bacterioci dal

Cephalosporins… 

  

Adverse effects[Toxicity] Hypersensitivity [Allergy]. Skin rash, Anaemia, Jaundice, Superinfection

Uses 1 Osteomyelitis 1 Surgical prophylaxis 2 Orbital cellulites 2 Otitis media 3 Typhoid 3 Gonnorrhoea 4 Severe hospital infections[IV Generation]

Aminogycosides Parenteral[Injectio n]  Amikacin  Gentamicin  Streptomycin  Kanamycin Topical  Framycetin  Neomycin

MOA  Inhibit bacterial protein synthesis.  Bactericidal.  Post antibiotic effect [Act even after blood concn is very low]

Aminogycosides….   



Uses Urinary tract infection Endocarditis Skin infections and Intestinal antiseptic [Neomycin] Tuberculosis [Streptomycin]

Adverse effects  Ototoxicity [hearing]  Nephro toxicity[Kidney]  Motor end plate blockade[Muscle paralysis] Contra indications  Renal failure  Hearing loss  Caution with muscle relaxants

Tetracyclines Classification  Short acting Tetracycline  Intermediate acting Demeclocycline,  Long acting Doxycycline, minocycline

MOA  Tetracyclines arrest bacterial protein synthesis[bind to 30S ribosome and ]  Broad spectrum  Bacteriostatic

Tetracyclines    

  

Uses Cholera Severe acne Syphilis Neonatal gonococcal conjunctivitis Rickettsial infections Trachoma Periodontal diseases:

Adverse effects  Superinfection [Diarrhoea],  Permanent discolouration of teeth and bone.  Phototoxicity,  Hepatotoxicity, Contra indications  Pregnancy  Children below 6 years

Chloramphenicol MOA  Inhibits bacterial protein synthesis. [binds to 50S ribosome]  Bacteriostatic  Broad spectrum [Like tetracycline]

  



Uses Typhoid fever Bacterial meningitis Anaerobic infections – B. fragilis Rickettsiae

Chloramphenicol Uses  Typhoid fever  Bacterial

meningitis  Anaerobic infections – B. fragilis  Rickettsiae

Adverse effects  Aplastic anemia [Bone marrow depression]  Grey baby syndrome in premature and infants  Allergy Contrandicatiojns  Neonates and infants

Fluoroquinolones

Classification First Gen.Fluoroquinolone s  Norfloxacin  Ciprofloxacin  Ofloxacin  Pefloxacin Second Gen.Fluoroquinolones  Lomefloxacin  Levofloxacin 

MOA  Inhibit bacterial DNA gyrase andDNA synthesis  Bactericidal

Fluoroquinolones… Uses

 UTI  Typhoid fever  Gonorrhoea  Gastrenteritis

   

   

ADE[Toxicity] Tendonitis, Tendon rupture Superinfection Hypersensitivity[Alle rgy] CI Pregnancy. Children, Adolescents and Nursing mothers

Macrolides    

Classification Erythromycin, Azithromycin, Clarithromycin, Roxithromycin,



 

 

MOA Inhibiting bacterial protein synthesis PK Emycin enzyme inhibitor Hence produces toxicity if given with some drugs Azithromycin is nothence safer Azithromycin long

Macrolides 

    

Uses As an alternative for penicillin allergic individuals Bronchitis Chancroid Diphtheria Legionella infections Pertussis (Whooping cough)

ADE[Toxicity]  Epigastric distress, nausea, vomiting and diarrhoea  Jaundice Drug interactions  Inhibits enzymes[EMycin]  Hence produces cardiac toxicity with Terfanadine

Anti viral drugs

MOA viruses are merely genetic information surrounded by a protein coat. 3. Fusion inhibition 4. Reverse transcriptase inhibition 5. Protease inhibition 6. Inhibit DNA synthesis

Anti viral drugs……

Uses 2. Herpes 3. AIDS 4. Influenza

ADE[Toxicity]  Local stinging sensation  Nausea , vomiting  Anemia  Neutropenia Drug interactions  Common with PIs

Anti viral drugs

MOA viruses are merely genetic information surrounded by a protein coat. 3. Fusion inhibition 4. Reverse transcriptase inhibition 5. Protease inhibition 6. Inhibit DNA synthesis

Antifungal drugs Classification

Anti biotics: Amphoterecin-B[AMB], Griseofulvin Azoles: Clotrimazole Econozole Miconozole Flucanozole 3. Others: Flucytosine[5-FC] Terbinafine 4. Topical: Tolnaftate Whitfield’s ointment

 





MOA Differs with compound Amph B-Makes cell wall porous[Micropore] Griseofulvin inhibits mitosis[Cell division] Azoles inhibit enzymes required to synthesize cell wall

Antifungal drugs….. Uses

1. Systemic and topical fungal infections 2. Taenia versicolor 3.T.Cruris 4. Candidiasis 5.Histoplasmosis

Adverse effects 2. AMB is nephro toxic 3. Some azoles inhibit synthesis of androgens 4. Hair loss, Gynecomastia DI • Ketoconazole may produce serious dru interactions with

Anticancer drugs Classification

Alkylating agents Cyclophosphamide, Cisplatin

Antimetabolites Methotrexate, Antibiotics: Doxorubicin, Daunaorubicin Natural products Vincristine, Vinblastine Hormones and antagonists

MOA  Varies with different agents  Inhibit cell division at different phases  Inhibit cell metabolism[Eg.Folic acid]

Anticancer drugs Uses

1. Different types of malignancy 3.Some are used as immunomodulato rs 4.Methotrexate is also used in rhematoid arthritis 5.Mostly used in combinations

Adverse effects

2. The acute -nausea,

vomiting, 3. Irritants, extravasation 4. Bonemarrow suppression 5. Alopecia 6. Immunosuppression 7. Terratogenic AE: Specific treatment • Cisplatin-VomitingOndansetron • CyclophosfamideCystitis-MESNA • Methotrexate-

Immunomodulators

Immunity • Advantages Required to fight against foreign bodies-INFECTION  When immunity is decreased[Eg.AIDS] IMMUNOSTIMULANTS are used • Disadvantages  Rejects foreign bodies.Eg. Kidney transplants  In such cases IMMUNO SUPPRESSANTS are

Classification • Immuno suppressants 3. Specific T-cell inhibitors Cyclosporine 2. Cytotoxic drugs Methotrexate, Cyclophosphamide 3. GlucocorticoidsPrednisolone 4. Monoclonal antibodies • Immuno stimulants

Immunomodulators

Immuno suppressants  MOA: In general inhibit T cell proliferation which is required for development of immunity  USES: As anti-rejection drug in organ transplantation  ADE

Immuno stimulants  MOA: Non-specific stimulation of immune system  BCG VaccineBladder cancer  Some times used non specifically in various infections, cancers

Anti-tubercular drugs • • • •

•

Classification Mycobacterium tuberculosis First line drugs:[Less toxic More efficient] Isoniazid, Rifampicin, Ethambutol, Pyrazinamide, Streptomycin Second line drugs: Ofloxacin, Ciprofloxacin, Levofloxacin, Ethionamide,

DRUG

MOA

ADE

INH

[-]Cell wall Mycolic acid synthesis

Rifampici n

Periphera l Neuritis [Prevente d by Pyridoxin e] Red

[-] Nucleic urine, acid Liver synthesis toxicity

Pyrazinami [-] de Mycolic

Liver toxicity

Ethambut acid [-] cell EYE-optic ol wall neuritis synthesis in Streptomy [-]Protein children Nephro, cin

synthesis vestibula r

TB Drug regimens-DOTS  TB is curable  Short course treatment- DOTS-Directly    

Observed Treatment Short course Depending upon seriousness[Category} treatment lasts 6 months to 8 months 3 or 4 drugs for 2 months-INITIAL PHASE 2 or 3 drugs for 4 to 6 monthsContinuation phase Treatment of Multi Drug Resistant [MDR] requires longer duration

Anti-Leprosy drugs • Mycobacteria

Leprae • Drugs Dapsone Rifampicin Clofazamine Ofloxacin, Minocycline, Clarithromycin

Drug

MOA

ADE

Dapsone

[-]F.Acid

•Anemia, •Nausea • vomiting

Rifampici n

[-] Nucleic acid synthesis

•Red urine, • Liver toxicity

Clofazami [-]DNA ne function

•Skin discolour ation •Nausea, Vomiting

Anti-Leprosy drugs  Leprosy curable  Treatment

 Pauci bacillary 6

Months  Multi Bacillary 12 months-12 months

 Rifampicin-

Once a monthSuprevised  Clofazamina and Dapsone -Daily

Malaria

• Falciparum and

vivax malaria • Falciparum malaria-No recurrence • Vivax malariaRecurs • Classification 5.Used for clinical cure• MildChloroquine,

Drugs

Adverse Effects

Chloroqui •Nausea, ne vomiting

•Retinal damage •Nausea, vomiting •Cinchonism Primaquin •Anemia in e G6PD defeciency pts. Quinine

Anti –Amoebic Drugs

Classification Luminal-Diloxanide furoate Extra intestinal only-Chloroquine Intestinal and extra intestinalMetronidazole, Emitine A] Intestinal and extra intestina

Drugs

Adverse Effects

Metronidazol •Nausea, e •Vomiting

•Interaction with alcohol

Anthemintic drugs Classification Round worm Hook worm Thread worm Albendazole Mebendazole Pyrantel Filaria-Diethyl carbamazine Tape wormPraziquintal, Albendazole Hydatid-Albendazole

Albendazole Mebendazole Pyrantel ROUND WORM

Albendazole Mebendazole Pyrantel

HOOK WORMS

Albendazole Mebendazole Pyrantel

HOOK WORMS

ariasis rmectin and Diethyl Carbamazine

Tape Worm Praziquintal, Albendazole

Individual agents

• Classification • MOA • ADE • Uses • Contra indications  Penicillins. Cephalosporins.Co-trimoxazole  Aminoglycosides.Tetracyclines.

Chloramphenicol  Quinolones.Macrolides  Antifungal, Antiviral  Anti-cancer  Immunomodulators  TB, leprosy, amoebiasis, antihelminthics