Antiviral drugs are an important topic in pharmacology for B.Pharm, D.Pharm, GPAT, and pharmacist recruitment examinations. Questions commonly cover antiviral drug classification, mechanisms of action, therapeutic uses, adverse effects, and differences between drugs used for various viral infections.
In this article, you will find 30 important multiple-choice questions on antiviral drugs, along with correct answers and simple explanations to help you understand the concepts and prepare for pharmacy examinations.
📝Top 30 MCQs on Antiviral Drugs
1. Which antiviral drug is commonly used to treat herpes simplex virus infections?
A. Oseltamivir
B. Acyclovir
C. Zidovudine
D. Fluconazole
Correct Answer: B. Acyclovir
Explanation: Acyclovir is an antiviral drug used to treat infections caused by herpes simplex viruses and varicella-zoster virus. It is activated preferentially in infected cells and inhibits viral DNA synthesis.
2. What is the primary mechanism of action of acyclovir?
A. Inhibition of viral neuraminidase
B. Inhibition of viral DNA polymerase
C. Inhibition of HIV protease
D. Inhibition of viral entry into all host cells
Correct Answer: B. Inhibition of viral DNA polymerase
Explanation: After activation by viral thymidine kinase in susceptible infected cells, acyclovir inhibits viral DNA polymerase and causes DNA chain termination. This prevents effective viral DNA replication.
3. Which drug is a neuraminidase inhibitor used to treat influenza?
A. Acyclovir
B. Oseltamivir
C. Zidovudine
D. Tenofovir
Correct Answer: B. Oseltamivir
Explanation: Oseltamivir inhibits influenza neuraminidase, an enzyme that helps newly formed influenza viruses leave infected cells. It can be used for influenza treatment and, in selected circumstances, prevention.
4. Zidovudine belongs to which class of antiretroviral drugs?
A. Protease inhibitors
B. Nucleoside reverse transcriptase inhibitors
C. Integrase inhibitors
D. Neuraminidase inhibitors
Correct Answer: B. Nucleoside reverse transcriptase inhibitors
Explanation: Zidovudine, also called AZT, is a nucleoside reverse transcriptase inhibitor (NRTI). It interferes with HIV reverse transcriptase and inhibits viral DNA synthesis.
5. Which enzyme converts HIV RNA into DNA?
A. DNA ligase
B. Reverse transcriptase
C. Neuraminidase
D. Cyclooxygenase
Correct Answer: B. Reverse transcriptase
Explanation: HIV uses reverse transcriptase to convert its RNA genetic material into DNA. This DNA can subsequently integrate into the host cell’s genome.
6. Which of the following is an HIV integrase strand transfer inhibitor?
A. Dolutegravir
B. Oseltamivir
C. Acyclovir
D. Amantadine
Correct Answer: A. Dolutegravir
Explanation: Dolutegravir inhibits HIV integrase, preventing the integration of viral DNA into the host cell’s DNA. Integrase inhibitors are an important class of antiretroviral medicines.
7. Which drug is an HIV protease inhibitor?
A. Darunavir
B. Acyclovir
C. Oseltamivir
D. Zidovudine
Correct Answer: A. Darunavir
Explanation: Darunavir inhibits HIV protease, an enzyme required to process viral polyproteins into functional proteins. This prevents the formation of fully mature infectious viral particles.
8. Which antiviral drug is commonly used in the treatment of cytomegalovirus infections?
A. Ganciclovir
B. Terbinafine
C. Metformin
D. Amoxicillin
Correct Answer: A. Ganciclovir
Explanation: Ganciclovir is used to treat selected cytomegalovirus (CMV) infections, particularly in high-risk patients. Important adverse effects include bone marrow suppression.
9. Which drug is used to treat influenza by inhibiting the viral cap-dependent endonuclease?
A. Baloxavir marboxil
B. Acyclovir
C. Tenofovir
D. Ganciclovir
Correct Answer: A. Baloxavir marboxil
Explanation: Baloxavir marboxil inhibits influenza virus cap-dependent endonuclease, an enzyme involved in viral mRNA production. It is used for selected cases of influenza.
10. Which of the following is an important adverse effect of zidovudine?
A. Bone marrow suppression
B. Permanent hearing loss in every patient
C. Severe hypoglycemia in every patient
D. Increased production of insulin
Correct Answer: A. Bone marrow suppression
Explanation: Zidovudine can cause bone marrow suppression, including anemia and neutropenia. Blood counts may need monitoring during treatment.
11. Which antiviral drug is used as part of combination therapy for chronic hepatitis B?
A. Tenofovir
B. Oseltamivir
C. Acyclovir
D. Baloxavir
Correct Answer: A. Tenofovir
Explanation: Tenofovir is a nucleotide analogue reverse transcriptase inhibitor with activity against hepatitis B virus (HBV). It is one of the preferred medicines for many patients requiring treatment for chronic hepatitis B.
12. Which statement about hepatitis C treatment is correct?
A. Antibiotics are the standard treatment for all hepatitis C infections.
B. Direct-acting antivirals target specific viral proteins.
C. Oseltamivir is the standard treatment for hepatitis C.
D. Acyclovir cures all hepatitis C infections.
Correct Answer: B. Direct-acting antivirals target specific viral proteins.
Explanation: Hepatitis C is treated with direct-acting antiviral (DAA) combinations that target specific viral proteins. Modern DAA regimens can cure most treated infections, although the appropriate regimen depends on clinical factors.
13. Which of the following is a direct-acting antiviral used against hepatitis C?
A. Sofosbuvir
B. Acyclovir
C. Zidovudine
D. Oseltamivir
Correct Answer: A. Sofosbuvir
Explanation: Sofosbuvir inhibits the hepatitis C virus NS5B RNA-dependent RNA polymerase. It is used in combination with other antiviral medicines.
14. Which viral enzyme is inhibited by HIV protease inhibitors?
A. HIV protease
B. Influenza neuraminidase
C. Human cyclooxygenase
D. Bacterial DNA gyrase
Correct Answer: A. HIV protease
Explanation: HIV protease inhibitors prevent the cleavage of viral polyproteins into functional proteins. This interferes with viral maturation and reduces the production of infectious viral particles.
15. Which of the following is NOT an antiviral drug?
A. Acyclovir
B. Oseltamivir
C. Zidovudine
D. Fluconazole
Correct Answer: D. Fluconazole
Explanation: Fluconazole is an antifungal medicine used for selected fungal infections. Acyclovir, oseltamivir, and zidovudine are antiviral medicines used against different viruses.
16. Which drug is a nucleotide reverse transcriptase inhibitor used in HIV treatment?
A. Tenofovir
B. Fluconazole
C. Oseltamivir
D. Acyclovir
Correct Answer: A. Tenofovir
Explanation: Tenofovir is a nucleotide analogue reverse transcriptase inhibitor. It is used in antiretroviral treatment and also has activity against hepatitis B virus. The exact formulation and combination depend on the treatment indication.
17. Which of the following best describes the action of antiviral drugs?
A. They act only against bacteria.
B. They interfere with specific stages of viral replication.
C. They always destroy viruses directly outside host cells.
D. They work by increasing blood glucose.
Correct Answer: B. They interfere with specific stages of viral replication.
Explanation: Antiviral drugs act on particular viral enzymes, proteins, or stages of the viral life cycle. Their effects depend on the drug and the virus being treated.
18. Which antiviral drug is used to treat selected cases of COVID-19 in eligible patients?
A. Nirmatrelvir combined with ritonavir
B. Fluconazole alone
C. Zidovudine alone
D. Oseltamivir alone
Correct Answer: A. Nirmatrelvir combined with ritonavir
Explanation: Nirmatrelvir inhibits the SARS-CoV-2 main protease. Ritonavir increases nirmatrelvir exposure by inhibiting its metabolism. The combination is used for eligible patients according to current clinical guidance, with particular attention to drug interactions and kidney function.
19. Which antiviral drug inhibits the SARS-CoV-2 RNA-dependent RNA polymerase?
A. Remdesivir
B. Darunavir
C. Fluconazole
D. Zidovudine
Correct Answer: A. Remdesivir
Explanation: Remdesivir is a nucleotide analogue prodrug that inhibits viral RNA-dependent RNA polymerase. It is used in selected COVID-19 treatment settings.
20. Which of the following is a common adverse effect of oseltamivir?
A. Nausea and vomiting
B. Permanent blindness in every patient
C. Severe hypoglycemia in every patient
D. Complete loss of hearing in every patient
Correct Answer: A. Nausea and vomiting
Explanation: Nausea and vomiting are among the common adverse effects of oseltamivir. Taking it with food may improve gastrointestinal tolerability.
21. Why are combinations of antiretroviral drugs used in HIV treatment?
A. To treat bacterial infections simultaneously
B. To suppress viral replication more effectively and reduce resistance risk
C. To eliminate the need for adherence
D. To prevent all adverse effects
Correct Answer: B. To suppress viral replication more effectively and reduce resistance risk
Explanation: Combination antiretroviral therapy targets HIV at multiple stages of its life cycle. It helps achieve sustained viral suppression and lowers the risk of resistance when taken as prescribed.
22. Which statement about antibiotics and antiviral drugs is correct?
A. Antibiotics routinely cure viral infections.
B. Antiviral drugs are used against specific viral infections.
C. Antivirals and antibiotics are interchangeable.
D. Antibiotics inhibit every viral enzyme.
Correct Answer: B. Antiviral drugs are used against specific viral infections.
Explanation: Antibiotics treat susceptible bacterial infections, whereas antiviral drugs target particular viruses or viral processes. Antibiotics do not treat uncomplicated viral infections unless a bacterial infection also requires treatment.
23. Which of the following is a major concern with prolonged or inappropriate antiviral use?
A. Development of antiviral resistance
B. Guaranteed immunity against every virus
C. Complete prevention of all adverse effects
D. Conversion of every virus into a bacterium
Correct Answer: A. Development of antiviral resistance
Explanation: Some viruses can develop mutations that reduce their susceptibility to antiviral medicines. Correct drug selection, appropriate dosing, and adherence help reduce the risk of treatment failure and resistance.
24. Which drug is associated with the treatment of herpes zoster?
A. Valacyclovir
B. Oseltamivir
C. Zidovudine
D. Sofosbuvir
Correct Answer: A. Valacyclovir
Explanation: Valacyclovir is a prodrug of acyclovir. It is used to treat herpes zoster and selected herpes simplex virus infections. Early treatment of shingles can be beneficial.
25. Which enzyme is targeted by acyclovir after the drug is activated in susceptible infected cells?
A. Viral DNA polymerase
B. HIV protease
C. Influenza neuraminidase
D. Hepatitis C NS5A protein
Correct Answer: A. Viral DNA polymerase
Explanation: The active form of acyclovir inhibits viral DNA polymerase and terminates viral DNA chain elongation. This mechanism explains its activity against susceptible herpesviruses.
26. Which antiviral drug class prevents HIV DNA from integrating into the host genome?
A. Integrase inhibitors
B. Neuraminidase inhibitors
C. Antifungal azoles
D. Histamine receptor blockers
Correct Answer: A. Integrase inhibitors
Explanation: HIV integrase inhibitors block the integration step of the viral life cycle. Dolutegravir and bictegravir are examples of this class.
27. Which statement about influenza antiviral treatment is correct?
A. Antiviral treatment may be particularly important in patients at high risk of complications.
B. All influenza infections require antibiotics.
C. Antiviral treatment is effective only after several weeks of symptoms.
D. Acyclovir is the preferred antiviral for every influenza infection.
Correct Answer: A. Antiviral treatment may be particularly important in patients at high risk of complications.
Explanation: Influenza antivirals can be especially important for hospitalized patients, people with severe or progressive illness, and people at increased risk of complications. Early treatment is generally preferred, and clinical guidance should be followed.
28. Which of the following is a potential adverse effect of ganciclovir?
A. Bone marrow suppression
B. Increased production of red blood cells in all patients
C. Guaranteed prevention of kidney injury
D. Permanent immunity against CMV
Correct Answer: A. Bone marrow suppression
Explanation: Ganciclovir can cause neutropenia, anemia, and other blood-related adverse effects. Appropriate laboratory monitoring is important during treatment.
29. Which of the following is an example of a nucleoside analogue used against herpesviruses?
A. Acyclovir
B. Oseltamivir
C. Darunavir
D. Ritonavir
Correct Answer: A. Acyclovir
Explanation: Acyclovir is a guanosine analogue that inhibits viral DNA synthesis after activation in susceptible infected cells. Oseltamivir is a neuraminidase inhibitor, while darunavir and ritonavir are HIV protease inhibitors.
30. Which statement about antiviral therapy is most accurate?
A. One antiviral drug is effective against every virus.
B. Antiviral selection depends on the virus, clinical condition, and patient-specific factors.
C. Antiviral medicines never interact with other drugs.
D. Antiviral treatment always eliminates latent viruses from the body.
Correct Answer: B. Antiviral selection depends on the virus, clinical condition, and patient-specific factors.
Explanation: Antiviral medicines have different targets and indications. The choice of treatment depends on factors such as the infecting virus, disease severity, kidney and liver function, pregnancy status where relevant, and possible drug interactions.
📑Quick Revision: Important Antiviral Drugs
- Acyclovir: Herpes simplex and varicella-zoster infections.
- Valacyclovir: Prodrug of acyclovir; used for selected herpesvirus infections.
- Oseltamivir: Influenza neuraminidase inhibitor.
- Baloxavir marboxil: Influenza cap-dependent endonuclease inhibitor.
- Zidovudine: Nucleoside reverse transcriptase inhibitor used in HIV treatment.
- Tenofovir: Nucleotide reverse transcriptase inhibitor with activity against HIV and hepatitis B virus.
- Dolutegravir: HIV integrase inhibitor.
- Darunavir: HIV protease inhibitor.
- Ganciclovir: Used for selected CMV infections.
- Sofosbuvir: Hepatitis C NS5B polymerase inhibitor.
- Remdesivir: SARS-CoV-2 RNA-dependent RNA polymerase inhibitor.
- Nirmatrelvir/ritonavir: Combination used for eligible patients with COVID-19.
📋Frequently Asked Questions (FAQs)
1. Which antiviral drugs are important for pharmacy exams?
Acyclovir, oseltamivir, zidovudine, tenofovir, dolutegravir, darunavir, ganciclovir, and sofosbuvir are useful examples to study. Learn their drug classes, mechanisms of action, major uses, and important adverse effects.
2. What is the difference between antibiotics and antiviral drugs?
Antibiotics act against susceptible bacteria, while antiviral drugs interfere with specific stages of viral replication. Antibiotics do not routinely treat viral infections.
3. Which antiviral drug is used for herpes infections?
Acyclovir and valacyclovir are commonly used for selected herpes simplex and varicella-zoster virus infections. The appropriate drug depends on the type and severity of infection.
4. Which antiviral drug is used for influenza?
Oseltamivir is a commonly used antiviral for influenza. Baloxavir marboxil is another option for selected patients.
5. Why are antiviral drugs important in pharmacology?
Antiviral drugs are important because they can reduce viral replication, treat specific viral infections, and improve outcomes in appropriate patients. Their mechanisms and uses are frequently studied in pharmacology examinations.
🎯 Conclusion
Antiviral drugs are an important part of pharmacology and pharmacy examination preparation. Understanding their classification, mechanisms of action, therapeutic uses, and adverse effects makes MCQs easier to solve.
Related Reading: Explore our detailed notes on Antiviral Drugs: Classification, Mechanism, Uses and Side Effects.
Disclaimer: This article is for educational purposes and pharmacy exam preparation. It is not a substitute for professional medical advice or treatment.
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