Sulfonamides, Trimet, Quinolones Flashcards
Sulfacetamide
Use: conjunctivitis , corneal ulcer, and other superficial ocular infections
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: irritation, stinging or burning
Silver sulfadiazine
Use: burns
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: irritation, stinging or burning
Triple sulfa
Use: for vaginitis caused by H. Vaginalis
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: irritation, stinging or burning
Sulfisoxazole
Use: uncomplicated urinary tract infections
Usually used with phenazopyridine
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Sulfamethoxazole
Use: uncomplicated urinary tract infections
Usually used with trimethoprim
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Sulfadoxine
Use: malaria
Usually used with pyramethamine
Very long lasting
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Sulfadiazine
Use: used to treat toxoplasmosis
Usually used with pyramethamine
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Dapsone
Use: to treat leprosy
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Sulfasalazine
Use: to treat inflammatory bowel disorder
Not absorbed- active ingredient is 5-aminosalicylic acid
MOA: competitively inhibit the conversion of PABA to folic acid mediated by the enzyme dihydropteroate synthase which ultimately inhibits DNA synthesis
Side effects: hypersensitivity -skin rash, fever, urticaria. Cross sensitivity with other sulfa drugs. N/v/d, crystalluria, allergic nephritis, hematopoietic disturbances, hemolytic anemia in pts with g6pd deficiency, kern icterus in newborns by displacement of serum albumin.
Trimethoprim
MOA: inhibits dihydrofolate reductase of bacteria 10,000 times more efficiently than mammalian cells . Bacteriostatic.
Use: used alone for acute UTIs
Used in combo with sulfamethoxazole for other infections
Adverse effects: similar to sulfa drugs plus rare hematopoietic disturbances ( megalomaniac anemia, leukopenia) use folinic acid to prevent hematologic toxicity.
Uses for trimethoprim and sulfamethoxazole
Pneumonia - due to pneumocystis carinii (oral and IV)
GI infections - shigella enteritis
Systemic infections caused by norcardia and salmonella
UTIs and respiratory infections caused by h. Influenza or streptococcus pneumonae
Listeria meningitis
Quinolones (fluoroquinolones)
Synthetic fluoridated antimicrobial agents
Moa: block DNA synthesis by in hi biting topoisomerase II ( DNA gyrate) and topoisomerase IV . This prevents unwinding of supercooled DNA that is required for normal transcription and duplication . IV deals with the separation of replicated chromosomal DNA.
Ciprofloxacin
Gram - and some activity against gram + , h. Influenzae
Levofloxacin , gemifloxacin, moxifloxican
Improved activity against gram + particularly s. Pneumoniae
Quinolone Resistance occurs due to what.
Microbial modification of DNA gyrase or topoisomerase IV structure.
Alteration of members never me ability into the bacterial cell
Sulfonamides gain resistance how
Microbial overproduction of PABA
Structural changes that occur in bacterial dihydropteroate synthase
Decreased permeability
Use of Ciprofloxacin
Topical : eye- conjunctivitis, corneal ulcer, and other superficial ocular infections
Oral: resistant uti, infectious diarrhea( shigella, salmonella, e. Coli, campylobacter) typhoid fever, single dose to treat gonorrhea, pseudomonas , anthrax
Clinical use of levofloxacin
Oral: resistant uti, infectious diarrhea( shigella, salmonella, e. Coli, campylobacter) typhoid fever, single dose to treat gonorrhea, pseudomonas , anthrax , osteomyelitis and skin structure Infections
Respiratory tract infections including cap, reserved for pts with comorbidity or risk factors
Clinical uses of gemifloxacin
Oral: osteomyelitis and skin structure Infections
Respiratory tract infections including cap, reserved for pts with comorbidity or risk factors
Moxifloxican clinical uses
Oral: osteomyelitis and skin structure Infections and single dose for treatment of gonorrhea
Respiratory tract infections including cap, reserved for pts with comorbidity or risk factors
Sides effects of Quinolones
Topical - irritation, stinging or burning
Systemic effects
- n/v/d
-‘photosensitivity, CNS disturbances : dizzy, confusion, hallucinations)
- damage growing cartilage : no children or preggers
- prolong qt interval : don’t use in pts taking antiarrhythemiad and other drugs that prolong that qt ( erythromycin, tricyclic antidepressants)
