Term
| Examples of Metabolism Inhibitors |
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Definition
| Folate Synthesis Inhibitors and Energy Production Pathway Inhibitors. |
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Term
| Folate Synthesis Inhibitors |
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Definition
i.Sulfonamides
ii.Diaminopyrimidines
iii.Combination = “Potentiated Sulfonamides” |
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Term
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Definition
| Folate Synthesis Inhibitors |
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Term
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Definition
| Folate Synthesis Inhibitors |
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Term
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Definition
| Combination of sulfonamides and Diminopyrimidines |
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Term
| Energy Production Pathway Inhibitor Examples |
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Definition
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Term
| Examples of Sulfonamides “Sulfa” drugs |
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Definition
Sulfamethoxazole
Sulfadiazine
Sulfamethoxine |
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
| Sulfonamide Mechanism of Action |
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Definition
1) penetrate bacteria
2) Compete with PABA and inhibit folic acid synthesis in bacteria and some protozoans
3) activiry decreased in pus or necrotic tissue |
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Term
| Sulfonamides Spectrum of Activity |
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Definition
1) bacteriostatic
2)Time Dependent
3) broad spectrum (G +, G-, aerobes, not Anaerobes tho)
4) mostly extracellular
5) some protozoa |
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Term
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Definition
Absorption: partial oral
Distribtution: extracellular, good in fluids
Metabolism:liver metabolism
Elimination:mixed liver and renal elimination |
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Term
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Definition
| Additive or Synergistic when added with Diaminopyrimidines: "Potenitated Sulfomides" |
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Term
| Sulfonamide Adverse Reactions |
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Definition
relatively safe.
--dose dependent effects.
--Thyroid function prohibited (dogs)*try to avoid in animals with hypothyroid or adjust T4)
--KeratoConjuctivitis Sicca (KCS) (dogs)
*avoid in dogs with eye disease
--Urinary disturbances (rare)
**Allergic reactions more rare then penicillin reactions but do not use in Dobermans
**Banned off label use in Lactating dairy cows |
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Term
| Diaminopyrimidines Examples |
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Definition
-"oprim" drugs
-Trimethoprim
-Ormetoprim |
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Term
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Definition
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Term
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Definition
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Term
| Diaminopyrimidines Mechanism of Action |
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Definition
| Prevent activation of folic acid to folinic acid |
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Term
| Diaminopyrimidines Spectrum of Action |
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Definition
-Bacteriostatic
-Time-dependent
-Broad Spectrum (not anaerobes tho)
-Protozoa |
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Term
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Definition
Absorption: well absorbed orally
Distribution: Extra and intra-good for fluids and deep tissues.
Metabolism: liver metabolism
Elimination: liver excretion |
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Term
| Diaminopyrimidines Combinations |
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Definition
| "potentiated sulfonamides" |
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Term
| Diaminopyrimidines Adverse Reactions |
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Definition
Dose Dependent Folate Deficiency (can hurt mammalian cells too!)
--blood cytopenia (dosed for more than 3 weeks)
--reversible
--avoid in pregnant aniamsl
--supplement with folic acid and folinic acid |
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Term
| Potentiated Sulfonamides Examples |
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Definition
Sulfamethoxazole + Trimethoprim
Sulfadimethoxine + Oremtoprim
Sulfadiazine + Trimethoprim |
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Term
| Rationale Behind the Potentiated Combinations |
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Definition
1) sequential mechanisms of action in the folic acid synthesis pathway
2) combination potentially bactericidal
3) extension of the spectrum to intracellular microbes
4) Extension of the tissue penetration (fluids and deep tissues) |
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Term
| Potentiated Sulfonamides Activity |
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Definition
-Bacteriostatic
-Time-dependent |
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Term
| Energy Production Pathway Inhibitors |
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Definition
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Term
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Definition
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Term
| Nitrofuran Mechanism of Action |
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Definition
| Deprive bacteria from a key energy production pathway and damage DNA. |
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Term
| Nitrofuran Spectrum of Activity |
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Definition
1) Bacteriostatic or cidal
2) Broad Spectrum (all four quads!)
3) Extracellular
4)Protozoa |
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Term
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Definition
Absorption: oral
Distribution: extracellular
Metabolism: liver
Elimination:renal --concentration in the urine |
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Term
| Nitrofuran Adverse Reactions |
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Definition
dose-dependent toxicity
--ok if used locally or at low dose for UTI
--drug allergies are relatively common |
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Term
| Nitrofuran Clincical Usage |
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Definition
-Locally: otits
-Systemically: UTI
-Banned in Food Animals completely |
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