GPT- Antibiotics Flashcards
Which antibiotic is a DNA gyrase inhibitor?
A) Trimethoprim
B) Quinolones
C) Sulfonamides
D) Bacitracin
B) Quinolones
Trimethoprim is an inhibitor of which enzyme?
A) DNA gyrase
B) DHF reductase
C) Reverse transcriptase
D) Bio synthetic pathways
B) DHF reductase
Which of the following antibiotics inhibits the enzyme PABA?
A) Zidovudine
B) Sulfonamides
C) Amphotericin B
D) Polymyxin B
B) Sulfonamides
Zidovudine is known to inhibit which enzyme?
A) Cell wall permeability
B) Reverse transcriptase
C) DHF reductase
D) DNA gyrase
B) Reverse transcriptase
Amphotericin B and Polymyxin B affect which cellular component?
A) DNA gyrase
B) DHF reductase
C) Cell wall permeability
D) Bio synthetic pathways
C) Cell wall permeability
Bacitracin is an inhibitor of which of the following?
A) Inhibitors of bio synthetic pathways
B) DNA gyrase inhibitors
C) DHF reductase inhibitor
D) Cell wall permeability
A) Inhibitors of bio synthetic pathways
What is the mechanism of resistance for β-lactams?
A) Active efflux from the cell
B) Hydrolysis, mutant PBP
C) Binding by immunity protein
D) RNA methylation, drug efflux
B) Hydrolysis, mutant PBP
Tetracycline resistance is primarily due to which process?
A) Overproduction of target
B) Active efflux from the cell
C) Inactivation by enzymes
D) Mutant DNA gyrase
B) Active efflux from the cell
How do bacteria commonly resist aminoglycosides?
A) Mutant DNA gyrase
B) Ribosomal methylation
C) Inactivation by enzymes
D) Reduced uptake into cell
C) Inactivation by enzymes
Resistance to sulfonamides is often due to what?
A) Reprogramming of D-ala-D-ala
B) Overproduction of target
C) Binding by immunity protein
D) Active efflux from the cell
B) Overproduction of target
Which mechanism leads to fluoroquinolones resistance?
A) Overproduction of target
B) Mutant DNA gyrase
C) Reduced uptake into cell
D) Hydrolysis, mutant PBP
B) Mutant DNA gyrase
Bleomycin resistance is achieved by what means?
A) Reduced uptake into cell
B) Binding by immunity protein
C) Ribosomal methylation
D) Active efflux from the cell
B) Binding by immunity protein
Chloramphenicol resistance occurs due to which process?
A) Reprogramming of D-ala-D-ala
B) RNA methylation, drug efflux
C) Reduced uptake into cell
D) Inactivation by enzymes
C) Reduced uptake into cell
Vancomycin resistance is characterized by which of the following?
A) Mutant DNA gyrase
B) Ribosomal methylation
C) Reprogramming of D-ala-D-ala
D) Binding by immunity protein
C) Reprogramming of D-ala-D-ala
Resistance to Quinupristin/Dalfopristin is achieved through:
A) Reduced uptake into cell
B) Ribosomal methylation
C) Inactivation by enzymes
D) Active efflux from the cell
B) Ribosomal methylation
What is the resistance mechanism for macrolides like Erythromycin?
A) Overproduction of target
B) RNA methylation, drug efflux
C) Binding by immunity protein
D) Reprogramming of D-ala-D-ala
B) RNA methylation, drug efflux
Sulfamethoxazole is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
C. UTI
Sulfasalazine is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
D. Ulcerative colitis
Silver sulfadiazine is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
A. Burn
Sulfacetamide is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
E. Ocular infection
Sulfisoxazole is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
B. Nocardiosis
Sulfadiazine + pyrimethamine is primarily used for:
A. Burn
B. Nocardiosis
C. UTI
D. Ulcerative colitis
E. Ocular infection
F. Toxoplasmosis
F. Toxoplasmosis
How does Amphotericin B work to treat fungal infections?
A) Inhibits DNA synthesis
B) Binds to ergosterol and creates pores in fungal cell membranes
C) Inhibits microtubule function
D) Blocks thymidylate synthetase
B) Binds to ergosterol and creates pores in fungal cell membranes
The mechanism of action for Flucytosine is:
A) Impairing the fungal cell membrane integrity
B) Inhibiting fungal cell wall synthesis
C) Inhibiting DNA and RNA synthesis by interfering with thymidylate synthetase
D) Disrupting microtubules within the fungal cells
C) Inhibiting DNA and RNA synthesis by interfering with thymidylate synthetase
Ketoconazole’s antifungal activity is primarily due to its ability to:
A) Inhibit DNA replication
B) Block cell wall beta-glucan synthesis
C) Inhibit ergosterol synthesis
D) Impair mitotic spindle formation
C) Inhibit ergosterol synthesis
Griseofulvin works against fungal infections by:
A) Competing with ergosterol
B) Inhibiting fungal microtubule function
C) Blocking the absorption of other antifungal agents
D) Disrupting fungal DNA synthesis
B) Inhibiting fungal microtubule function
Identify the category of the anti-fungal drugs:
a. Superficial Mycosis
b. Systemic Mycosis
c. Both
a. Superficial Mycosis
Identify the category of the anti-fungal drugs:
a. Superficial Mycosis
b. Systemic Mycosis
c. Both
b. Systemic Mycosis
Identify the category of the anti-fungal drugs:
a. Superficial Mycosis
b. Systemic Mycosis
c. Both
c. Both
What is the drug of choice for systemic mycotic infections?
A) Ketoconazole
B) Fluconazole
C) Amphotericin B
D) Griseofulvin
C) Amphotericin B
Which antifungal is the drug of choice for cryptococcal meningitis in AIDS patients?
A) Itraconazole
B) Amphotericin B
C) Fluconazole
D) Flucytosine
C) Fluconazole
The drug of choice for subcutaneous chromomycosis is:
A) Flucytosine
B) Griseofulvin
C) Itraconazole
D) Ketoconazole
C) Itraconazole
Which antifungal drug is associated with nephrotoxicity?
A) Flucytosine
B) Ketoconazole
C) Itraconazole
D) Amphotericin B
D) Amphotericin B
Nephrotoxicity
Hypotension
Arrhythmias
Neurologic effects
Fever
Hypochromic, normocytic anemia
Reversible bone marrow depression is a side effect of which drug?
A) Amphotericin B
B) Flucytosine
C) Ketoconazole
D) Itraconazole
B) Flucytosine
Reversible bone marrow depression
Increased hepatic enzymes
Nausea, vomiting, diarrhea
Gynecomastia is an adverse reaction found in patients taking:
A) Flucytosine
B) Amphotericin B
C) Ketoconazole
D) Itraconazole
C) Ketoconazole
Gynecomastia
Nausea, vomiting
Hepatotoxicity
Which of the following drugs can cause hypokalemia?
A) Ketoconazole
B) Itraconazole
C) Flucytosine
D) Amphotericin B
B) Itraconazole
Hypokalemia
GI distress
Hypertriglyceridemia
Hypertriglyceridemia is an adverse effect of:
A) Amphotericin B
B) Ketoconazole
C) Flucytosine
D) Itraconazole
D) Itraconazole
Hypokalemia
GI distress
Hypertriglyceridemia
What is the mechanism of action of Acyclovir?
A) Binds to thymidine kinase and acts as a guanine analog to terminate the viral DNA chain.
B) Inhibits viral DNA synthesis by direct action on viral DNA polymerase.
C) Phosphorylated metabolite incorporates into DNA, causing strand breaks.
D) Competes for pyrophosphate binding site on DNA polymerase.
A) Binds to thymidine kinase and acts as a guanine analog to terminate the viral DNA chain.
How does Ganciclovir work to inhibit viral replication?
A) By inhibiting thymidine kinase.
B) As a phosphate analog competing at the DNA polymerase binding site.
C) Through phosphorylation by thymidine kinase and inhibiting DNA polymerase.
D) By causing breaks in the viral DNA strands.
C) Through phosphorylation by thymidine kinase and inhibiting DNA polymerase.
Triflouride/ Idoxuridine’s antiviral activity is primarily because it:
A) Competes with pyrophosphate on viral DNA polymerase.
B) Acts as a guanine analog.
C) Is a thymidine analog that incorporates into DNA, causing strand breaks.
D) Inhibits viral DNA synthesis non-competitively.
C) Is a thymidine analog that incorporates into DNA, causing strand breaks.
The drug Vidarabine functions by:
A) Competing for pyrophosphate binding sites on reverse transcriptase.
B) Inhibiting viral DNA synthesis.
C) Terminating viral DNA chain elongation.
D) Causing the premature release of the viral genome.
B) Inhibiting viral DNA synthesis.
Foscarnet’s unique mechanism of action involves:
A) Binding to thymidine kinase.
B) Acting as a guanine analog to block DNA chain elongation.
C) Being a phosphate analog that competes for the pyrophosphate binding site on viral DNA polymerase and reverse transcriptase.
D) Incorporating into DNA and resulting in strand breaks
C) Being a phosphate analog that competes for the pyrophosphate binding site on viral DNA polymerase and reverse transcriptase.
What is the mechanism of action of Amantadine?
A) Inhibits viral RNA polymerase
B) Inhibits penetration and uncoating of the viral particle
C) Blocks viral DNA polymerase
D) Inhibits reverse transcriptase
B) Inhibits penetration and uncoating of the viral particle
Which of the following drugs inhibit viral DNA polymerase?
A) Oseltamivir
B) AZT, 3TC, DDI, DDC, DAT
C) Acyclovir, Foscarnet, Ganciclovir
D) Indinavir, -vir drugs
C) Acyclovir, Foscarnet, Ganciclovir
Foscarnet has a dual role and can inhibit which of the following enzymes?
A) Viral DNA polymerase and viral aspartate protease
B) Viral RNA polymerase and viral aspartate protease
C) Viral DNA polymerase and viral RNA polymerase
D) Neuraminidase and reverse transcriptase
C) Viral DNA polymerase and viral RNA polymerase
Which group of drugs inhibits reverse transcriptase?
A) Acyclovir, Foscarnet, Ganciclovir
B) AZT, 3TC, DDI, DDC, D4T
C) Amantadine and Oseltamivir
D) Indinavir and other -vir drugs
B) AZT, 3TC, DDI, DDC, D4T
AZT: Zidovudine (also known as Azidothymidine)
3TC: Lamivudine
DDI: Didanosine
DDC: Zalcitabine
D4T: Stavudine
The mechanism of action for Indinavir is to inhibit:
A) Viral RNA polymerase
B) Neuraminidase
C) Viral aspartate protease
D) Viral DNA polymerase
C) Viral aspartate protease
Oseltamivir is known to inhibit which enzyme?
A) Reverse transcriptase
B) Viral DNA polymerase
C) Neuraminidase
D) Viral aspartate protease
C) Neuraminidase
What is the drug of choice for treating Amebiasis?
A) Metronidazole
B) Stibogluconate
C) TMP-SMX
D) Pyrimethamine
A) Metronidazole
Which medication is primarily used to treat Giardiasis?
A) Nifurtimox
B) Metronidazole
C) Arsenicals
D) Sulfadiazine
B) Metronidazole
The recommended treatment for Leishmaniasis is:
A) Pyrimethamine
B) Stibogluconate
C) Metronidazole
D) Nifurtimox
B) Stibogluconate
For the management of Pneumocystosis, the first-line drug is:
A) TMP-SMX
B) Sulfadiazine
C) Metronidazole
D) Stibogluconate
A) TMP-SMX
Which drug is used to treat Trichomoniasis?
A) Nifurtimox
B) Stibogluconate
C) Metronidazole
D) TMP-SMX
C) Metronidazole
Toxoplasmosis is best treated with a combination of:
A) Metronidazole and Nifurtimox
B) Pyrimethamine and Sulfadiazine
C) Stibogluconate and TMP-SMX
D) Arsenicals and Metronidazole
B) Pyrimethamine and Sulfadiazine
The treatment for Chagas disease involves:
A) Arsenicals
B) Pyrimethamine
C) Nifurtimox
D) Stibogluconate
C) Nifurtimox
How does Metronidazole exert its antiprotozoal effect?
A) By inducing seizures in ectoparasites.
B) By inhibiting dihydrofolate reductase.
C) By activated nitro intermediates that bind to DNA and inhibit replication.
D) By inhibiting glucose transport in parasites.
C) By activated nitro intermediates that bind to DNA and inhibit replication.
What is the mechanism of action of Pyrimethamine in the treatment of Toxoplasmosis?
A) It inhibits the microtubule polymerization in parasites.
B) It induces seizures in ectoparasites.
C) It binds to beta-tubulin in parasites.
D) It inhibits dihydrofolate reductase.
D) It inhibits dihydrofolate reductase.
Lindane is used as an antiparasitic treatment because it:
A) Inhibits dihydrofolate reductase in parasites.
B) Induces seizures in ectoparasites.
C) Inhibits DNA synthesis in anaerobes.
D) Increases the muscular activity of worms.
B) Induces seizures in ectoparasites.
What is the presumed mechanism of action for Chloroquine as an antimalarial drug?
A) Inhibition of dihydrofolate reductase.
B) Crosslinking of glutathione.
C) Inducing changes in the pH of intracellular vacuoles and interfering with hemoglobin digestion in the parasite.
D) Directly interfering with the function of the parasite’s DNA.
C) Inducing changes in the pH of intracellular vacuoles and interfering with hemoglobin digestion in the parasite.
The mechanism of action for Mefloquine is:
A) Clearly defined and involves inhibition of folate synthesis.
B) Unclear but is thought to be similar to the action of Chloroquine.
C) Related to the crosslinking of glutathione.
D) Known to interfere with the parasite’s DNA.
B) Unclear but is thought to be similar to the action of Chloroquine.
How does Primaquine work against Plasmodium vivax in malaria treatment?
A) By inhibiting folate synthesis.
B) Through the crosslinking of glutathione.
C) By inducing seizures in ectoparasites.
D) By increasing muscular activity and causing paralysis of the parasite.
B) Through the crosslinking of glutathione.
Quinine’s antimalarial action is thought to be:
A) Well-understood with no resistance reported.
B) Not clear, though it interferes with the function of the parasite’s DNA.
C) Related to the induction of seizures in ectoparasites.
D) Involving the inhibition of dihydrofolate reductase.
B) Not clear, though it interferes with the function of the parasite’s DNA.
Pyrimethamine, along with Chloroguanide (Proguanil), Cycloguanil, and Pamaote, works by:
A) Crosslinking glutathione.
B) Changing the pH within the parasite’s vacuoles.
C) Inhibiting folate synthesis by interfering with dihydrofolate reductase.
D) Causing muscle contraction and paralysis in the parasite.
C) Inhibiting folate synthesis by interfering with dihydrofolate reductase.
What is the primary mechanism of action of Benzimidazoles in treating nematode infections?
A) Increases muscular activity in parasites.
B) Causes an influx of calcium ions across the parasite’s tegument.
C) Inhibits mitochondrial fumarate reductase and microtubule polymerization.
D) Inhibits cholinesterase enzyme in parasites.
C) Inhibits mitochondrial fumarate reductase and microtubule polymerization.
Praziquantel at low concentrations is used against cestodes because it:
A) Induces seizures in ectoparasites.
B) Increases muscular activity leading to contraction and spastic paralysis.
C) Inhibits microtubule polymerization.
D) Is a prodrug that is converted to dichlorvos.
B) Increases muscular activity leading to contraction and spastic paralysis.
At high concentrations, Praziquantel’s mechanism against trematodes involves:
A) Inhibition of mitochondrial fumarate reductase.
B) Blockage of glucose transport.
C) Influx of calcium ions causing damage and exposure of antigens.
D) Inhibition of cholinesterase enzyme.
C) Influx of calcium ions causing damage and exposure of antigens.
Metrifonate exerts its antiparasitic effects through which action?
A) Binding to beta-tubulin in parasites.
B) Inhibiting folate synthesis.
C) Being converted in vivo to dichlorvos and inhibiting cholinesterase enzyme.
D) Increasing muscular activity and causing spastic paralysis.
C) Being converted in vivo to dichlorvos and inhibiting cholinesterase enzyme.
Which of the following is an adverse drug reaction of Acyclovir?
A. Hematotoxicity
B. Photophobia
C. Crystalluria
D. Renal toxicity
C. Crystalluria
ADRs: Crystalluria, neurotoxicity
Ganciclovir is known to cause which of the following adverse reactions?
A. Neurotoxicity
B. Hematotoxicity
C. Seizures
D. Muscarinic blockade
B. Hematotoxicity
ADRs: Hematotoxic (granulocytopenia, thrombocytopenia)
Idoxuridine can cause:
A. Anemia
B. Photophobia
C. Crystalluria
D. Hypocalcemia
B. Photophobia
ADRs: Photophobia, irritation of conjunctiva and eyelid
Which of the following is NOT an adverse reaction of Foscarnet?
A. Renal toxicity
B. Hematotoxicity
C. Seizures
D. Diarrhea
B. Hematotoxicity
ADRs: Renal toxicity, seizures, hypocalcemia, fever, anemia, diarrhea
Amantadine can cause all of the following EXCEPT:
A. Livedo reticularis
B. Congestive heart failure
C. Teratogenic effects
D. Urinary retention
C. Teratogenic effects
ADRs:
Muscarinic blockade,
livedo reticularis,
depression,
CNS toxicity,
congestive heart failure,
orthostatic hypotension,
urinary retention
Which of the following is an adverse reaction of Ribavirin?
A. Hematotoxicity
B. Teratogenic effects
C. Crystalluria
D. Seizures
B. Teratogenic effects
ADRs: Teratogenic, decreased pulmonary function
Zidovudine is an analog of which nucleoside?
A. Thymidine
B. Adenosine
C. Cytosine
D. Non-nucleoside
A. Thymidine
Thymidine analog
Zidovudine (AZT)
Stavudine (d4T)
Didanosine (ddl) is an analog of which nucleoside?
A. Thymidine
B. Adenosine
C. Cytosine
D. Non-nucleoside
B. Adenosine
Zalcitabine (ddC) is an analog of which nucleoside?
A. Thymidine
B. Adenosine
C. Cytosine
D. Non-nucleoside
C. Cytosine
Stavudine is an analog of which nucleoside?
A. Thymidine
B. Adenosine
C. Cytosine
D. Non-nucleoside
A. Thymidine
Thymidine analog
Zidovudine (AZT)
Stavudine (d4T)
Nevirapine belongs to which category of antiviral drugs?
A. Thymidine analog
B. Adenosine analog
C. Cytosine analog
D. Non-nucleoside
D. Non-nucleoside
Non-Nucleoside Analogs:
1. Nevirapine
2. Delavirdine
Delavirdine belongs to which category of antiviral drugs?
A. Thymidine analog
B. Adenosine analog
C. Cytosine analog
D. Non-nucleoside
D. Non-nucleoside
Non-Nucleoside Analogs:
1. Nevirapine
2. Delavirdine
Azithromycin inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
- D. Translocation
Macrolides:
Erythromycin (prototype)
Clarithromycin
Azithromycin
Lincosamide:
Clindamycin
Chloramphenicol inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
C. Formation of peptide bond
Chloramphenicol (Chloromycetin)
Clarithromycin inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
D. Translocation
Macrolides:
Erythromycin (prototype)
Clarithromycin
Azithromycin
Lincosamide:
Clindamycin
Clindamycin inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
- D. Translocation
Macrolides:
Erythromycin (prototype)
Clarithromycin
Azithromycin
Lincosamide:
Clindamycin
Netilmicin inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
A. Formation of initiation complex
Aminoglycosides:
Amikacin
Netilmicin
Neomycin (typically used topically)
Tobramycin
Gentamicin
Streptomycin
Tetracycline inhibits protein synthesis by interfering with:
A. Formation of initiation complex
B. Amino acid incorporation
C. Formation of peptide bond
D. Translocation
B. Amino acid incorporation
Tetracyclines:
Tetracycline
Doxycycline
Demeclocycline
Minocycline
Oxytetracycline (Terramycin)
Erythromycin inhibits protein synthesis by interfering with:
- A. Formation of initiation complex
- B. Amino acid incorporation
- C. Formation of peptide bond
- D. Translocation
- D. Translocation
Macrolides:
Erythromycin (prototype)
Clarithromycin
Azithromycin
Lincosamide:
Clindamycin
