NRTIs

Question 1

What is the mechanism of action of the Nucleoside Reverse Transcriptase inhibitors (NRTIs)

Answer 1

• They mimic DNA bases,
• Acting as false substrates for reverse transcriptase

Question 2

Which 2 NRTIs act as Thymidine?

Answer 2

Zidovudine (AZT) + Stavudine (d4T)

Question 3

Which NRTI act as Guanosine?

Answer 3

Abacavir (ABC)

Question 4

Which 2 NRTIs act as Cytidine?

Answer 4

• Lamivudine (3TC) + emtricitabine (FTC)

Question 5

Which 2 NRTIs act as Adenosines?

Answer 5

• Tenofovir (TDF) + Dedanosine (ddI)

Question 6

Which NRTI well penetrates CSF?

Answer 6

Zidovudine (AZT)

Question 7

How do the NRTIs result to lactic acidosis in host cells?

Answer 7

They all inhibit mitochondrial DNA gamma, which is an enzyme that replicates the mitochondria of a host cell.

Question 8

How does lactic acidosis manifest itself in the human body? How do you know u are having lactic acidosis?

Answer 8

• Nausea
• Vomiting
• Abdominal pain
• Extreme tiredness

Question 9

What are the side effects from using Zidovudine (AZT)?

Answer 9

• Anemia
  -Myelosuppression
• Neutropenia
  -leucopenia
• peripheral neuropathy (damage to peripheral nerves)

Question 10

Wha are side effects of using stavudine (d4T)?

Answer 10

• Neutropenia
• Lipoatrophy

Question 11

What are the side effects from using abacavir (ABC)?

Answer 11

• Hypersensitivity reactions

Question 12

What are the side effects from using Tenofovir (TDF)

Answer 12

• Nephrotoxicity
• Bone loss

Question 13

What are side effects from using lamivudine (3TC) and Emtricitabine (FTC)?

Answer 13

Peripheral neurophathy

Question 14

What’s the metabolism pathway of the NRTIs?

Answer 14

Zidovudine (AZT) and Abacavir (ABC) undergo glucuronidation in the liver.

Question 15

Which drugs does Zidovudine interact with?

Answer 15

• Ganciclovir
• Valproate
• Probenecid

Question 16

What is the possible outcome from Zidovudine interaction with ganciclovir?

Answer 16

• increased
  hematological toxicity

Question 17

What is the possible outcome from Zidovudine interaction with valproate?

Answer 17

increase
AZT levels

Question 18

What is the possible outcome from Zidovudine interaction with probenecid?

Answer 18

delayed
AZT excretion

Question 19

When to not use Zidovudine? (The drug’s CI)

Answer 19

• Anemiac or patients with neutropenia

Question 20

What drugs does tenofovir interact with? And what are the outcomes?

Answer 20

• ddI- increases levels of
  didanosine
• ATV- decrease levels of
  atazanavir
• Kaletra®- Increase TDF
  levels

Question 21

When is Tenofovir contraindicated?

Answer 21

On patients with nephrotoxicity

Question 22

What are the adverse effects from Tenofovir use?

Answer 22

• Nephrotoxic,
• Hepatomegaly-enlargement of the liver beyond its normal size,
• HBV exacerbationswhen you stop using the drug