Chemotherapy Flashcards
Antibiotics that inhibit cytoplasmic bacterial (dna gyrase)Topoisomerase II and IV
Quinolones
Ciprofloxacin is the drug of choice for
anthrax
Possible cardiac complication of fluoroquinolone administration
Arrhythmia
often involves a prolonged QT interval
Common ADR of fluoroquinolones
Tendonitis
Tendon rupture
Leg cramps
Myalgia
Fluoroquinolones should not be taken simultaneously with antacid medications because they contain
metal cations
Impair absorption of the antibiotic
Transfer of DNA between bacteria via bacteriophage
Transduction
Staphylococcus aureus
Taking up DNA from resistant Bacteria via environment
Transformation
Pneumococci to penicillin G
Transfer of genetic material via sex pilus
Conjugation
Escherichia coli to streptomycin
Mechanism of antibacterial resistance
Inactivated enzyme Efflux pump Decreased entry Alterations in binding sites Absent metabolic pathway
Cross resistance
Organism showing antimicrobial resistance may show resistance to related Antimicrobial agents.
2 way:- sulphadiazine…sulphadoxine
1 way:- neomycin—> streptomycin
Superinfection is
New infection due to antimicrobial therapy for another infection.
Different causative agents.
Alter normal bacterial flora.
Chloramphenicol in infants may lead to
Grey baby syndrome
Sulphonamides to neonates can cause
Kernicterus
Genetic abnormality of G6PD defieciency lead to hemolysis on administration of
Sulfonamides
Pyrimethamine
Fluoroquinolones
Primaquine
Moa of sulphonamides
Competitively inhibit folate synthetase
Inhibit conversion of PABA to dihydrofolic acid.
Sulphonamides cross placental barrier (T/F)
T
ADR of sulphonamides
Crystalluria (hematuria, obstruction) Hypersenstivity(Stenven-Johnson) Hepatitis Bone marrow suppression Kernicterus*(neonate) Hemolytic anaemia*(g6pd)
Use of sulphadoxine with pyrimethamine
Plasmodium falciparum malaria tt(chloroquine resistant)
And sulphadiazine for toxoplasmosis
Silver sulphadiazine used for
Burn wounds(silver ions)
Sulphasalazine used for
IBD
Arthritis
Eye drops of aulphacetamide used in
Ophthalmic infection
Cotrimoxazole ratio
5:1
Sulphamethoxazole:trimethoprim
Bactericidal combination of bacteriostatics.(sequential blockade)
Trimethoprim act on
Dihydrofolate reductase.
Inhibits
dihyfrofolic acid —>tetrahydrofolic acid
ADR of cotrimoxazole
Skin rash GiT disturbing Exfoliative dermatitis (Steven-Johnson) Glossitis Stomatitis Megaloblastic anaemia Bone marrow suppression Leukopenia,neutropenia,thrombocytopenia
Uses of cotrimaxazole
UTI (gram negatives) Bacterial prostatitis Bronchitis Maxillary sinusitis Otitis media Bac diarrhoea P.jeroveci infection in HIV Nocardiosis Chancroid (H.ducreyi)
DOC for bac diarrhoea
Fluroquinolones
DOC for chancroid (H.ducreyi)
Azithromycin
Moa of fluoroquinolones
Inhibit
DNA gyrase(topoisomerase II) (gram-)
and
Topoisomerase IV (gram+)(separate daughter strand)
New fluoroquinolones for gram+ infection
Levofloxacin
Gemifloxacin
Moxifloxacin
ADR of fluroquinolones
GI Insomnia convulsions Confusion and hallucinations Hypersensitivity (urticaria, eosinophilia, photosensitivity) Tendonitis Cartilage damage(children) QT prolongation (moxifloxacin)
Fluroquinolone that causes QT prolonagation
Moxifloxacin
Uses of fluroquinolones
Uncomplicqted UTI Bacterial prostatitis Bac diarrhoea (traveller's diarrhoea) Typhoid STD (urethritis, cervicitis) Skin infection (diabetic foot infection) MTB Leprosy Conjunctivitis Pneumonia and bronchitis Anthrax Neutropenia
What is the MOA of all Cephalosporins?
Inhibition of Transpeptidase (PBP)
thereby inhibiting the cross-linking of peptidoglycan
3rd generation cephalosporin that is avoided in neonates as it competes for bilirubin binding sites on albumin, thereby causing jaundice or exacerbating physiological jaundice.
Ceftriaxone
The Gl toxicity of Cephalosporins is
Pseudomembranous colitis.
Co administration of cephalosporin and gentamicin causes
Severe Nephrotoxicity
ADR of cephalosporins
Hypersensitivity (urticaria,anaphylaxis) Cross reactivity with penicillin GIT iv - thrombophlebitis Nephrotoxicity Disulfiram rection(intolerance to alcohol) Thrombocytopenia Hypothrombenemia Platelet dysfunction
Advantage of using monobactem
Aztreonam
Lack cross reactivity with other beta lactams.
Inhibit bac cell wall synthesis
Only for gram-
Drugs for typhoid tt
3rd gen cephalosporins (ceftriaxon,cefoperazon)
Fluroquinolones (ciprofloxacin,levofloxacin,ofloxacin)
Azithromycin(multidrug condition)
Chloramphenicol
Drugs for MRSA
Clindamycin Doxycyclin Minocyclin Tigecyclin Linezolid Vancomycin(VRSA) Streptogramins Daptomycin Ceftaroline(5th gen cephalosporin) Teicoplanin
Drugs for staphylococcus infection
Penicillin Cephalosporin Carbepenems Tigecycline Aminoglycoside(netilmicin) Rifampin And drugs For MRSA
Active form of isoniazid
Iproniazid
Why rifampicin is called as sterilizing agent?
As it can act on all types of bacillery subpopulations.
Intracellular
Extracellular
Apurters(in caseous lesion)
Rifampicin + doxycycline for tt of
Brucellosis
Rifampicin + beta lactam for tt of
Staph infection
Endocarditis
Osteomylitis
Which drug stains the body fluids orange?
Rifampicin
Uses of rifampicin
TB + chemoprophylaxis Leprosy Meningitis(high conc. In nasopharynx) Staph infection(with beta lactam) Brucellosis(with doxycyclin)
Moa of streptomycin
Against extracellular bacilli
Active in alkaline pH
Intramuscular
ADR of streptomycin
Ototoxicity
Nephrotoxicity
Neuromuscular blockade
ADR of rifampicin
Inhibit cyt p450 Hepatotoxicity Flu like syndrome GIT Skin rash Itching flushing
Rifampicin should not be given with certain drugs as it increases thier metabolism
Oral contraceptive Anticoagulant Antidiabetics HIV protease inhibitor Non-neucleotide reverse transcriptase inhibitor(NNRTI)
Moa of pyrazinamide
Active in acidic pH
Intracellular bacilli
Inhibits mycolic acid synthesis by inhibiting fatty acid synthase
ADR of pyrazinamide
Dose dependant hepatotoxicity
Impair urate excretion (gout)
Hyperuricemia
Moa of Ethambutol
Inhibit arabinosyl transferases (cell wall synthesis)
Prevent resistance
Faster sputum conversion
No cross resistance
ADR of ethambutol
Hyperuricemia(gout) Optic neuritis Decreased visual acuity Colour vision defects(red-green) Skin rash itching joint pain
ADR of Isoniazid
Hepatotoxicity (rapid acetylators) Jaundice Peripheral neuritis (neurotoxicity) Arthralgia vit B6 deficiency (anaemia,encephalopathy, peripheral neuropathy) Drug induced SLE Psychosis Convulsions Metabolic acidosis Coma
Multibacillary leprosy include
Borderline(BB) Borderline lepromatous(BL) Lepromatous leprosy(LL)
Paucibacillary leprosy involves
Borderline tuberculoid(BT) Tuberculoid(TT) Intermediate leprosy(I)
Sulphone reaction of Dapsone is characterized by
Fever Dermatitis Pruritis Lymphadenopathy Methaemoglobinemia Anaemia Hepatitis
Characteristic side effect of clofazimine
Reddish black discolouration on skin
Pigmentation of conjunctiva,cornea
Discolouration of hair,tears,sweat,urine
Type 1 lepra reaction
Type 4 delayed
Multibacillary + paucibacillary
Inflammation of lesions
Tenderness and pain
Clofazimine
Prednisolone
Type 2 lepra reaction
Type 3 arthus type Erythema nodoaum Tender cutaneous and subcutaneous nodules Antigen involved Thalidomide (not in pregnancy) Aspirin Chloroquine Prednisolone Clofazimine
