Micro/simple/antiviral Drugs

Front 1

What are two imporatant steps of antiviral medications?

Back 1

1. They attack steps in actively replicating viruses and have no effect on latent viruses. (virustatic)2. Most are nucleotide analogues. They are taken up and used by viral DNA polymerase or reverse transcriptase. They inhibit the DNA polymerase or reverse transcriptase and are incorporated into the growing DNA strand.

Front 2

What is the difference between acyclovir and gancyclovir?

Back 2

They are guanine analogues against the herpes family.
To become active acyclovir must first be phosphorylated by a virus specific thymidine kinase. Most herpesviradae have this, while human cells do not.
The herpes cytomegalovirus lacks thymidine kinase, so it less effective against this.
Gancyclovir is not dependent on this viral enzyme. It kills all herpesviradae. It may be toxic to human cells such as neutrophils and platelets.

Front 3

With intravenous doses acyclovir may crystallize in the renal tubules, resulting in reversible kidney damage. TRUE/FALSE

Back 3

TRUE. CNS side effects are rare.

Front 4

What is famcyclovir and valacyclovir?

Back 4

These 2 new druga have the same mechanism as acyclovir but have the added effect of increased drug levels after oral absorption.
They are indicated only for herpes zoster and recurrent genital herpes in immunocompetent adults.

Front 5

Because of its toxicity gancyclovir is used only for CMV infections in immunocompromised hosts. TRUE/FALSE

Back 5

TRUE. Since zidovudine(AZT) also causes neutropenia, careful monitoring of neutrophil counts is recommended for patients on both AZT and gancyclovir.

Front 6

What is Foscarnet?

Back 6

This is a pyrophosphate analogue that inhibits DNA polymerase and reverse transcriptase. It covers the herpesviradae and HIV(minimal)

Front 7

When is Foscarnet used in HIV patients?

Back 7

CMV retinitis
Acyclovir resistant strains of herpesviridae.
nephrotoxicity and seizures have been noted as adverse effects.

Front 8

What is HAART?

Back 8

It is Highly Active AntiRetroviral Therapy.These are agents used in combination to suppress viral replication.

Front 9

There are atleast 14 different anti-HIV medications in the US today. TRUE/FALSE

Back 9

TRUE.

Front 10

Name 6 nucleoside reverse transcriptase inhibitors.

Back 10

1. AZT/ZDV
2. Didanosine
3. Zalcitabine
4. Stavudine
5. Lamivudine
6. Abacavir

Front 11

Name 3 non-nucleoside reverse transcriptase inhibitors.

Back 11

1. Nevirapine
2. Delaviridine
3. Efavirenz

Front 12

List 5 protease inhibitors.

Back 12

1. Saquinavir
2. Indinavir
3. Ritonavir
4. Nelfinavir
5. Amprenavir

Front 13

Antiviral therapy should be started for most patients with advanced HIV infection. However, if their CD4 count is high and their viral burden low, treatment can be delayed. TRUE/FALSE

Back 13

TRUE.

Front 14

The problem with Zidovudine is that HIV can develop resistance to Zudovudine when it is used alone. TRUE/FALSE

Back 14

TRUE.

Front 15

Lamivudine plays a very important role in the treatment of hepatitis B virus as monotherapy and in combination with interferon. TRUE/FALSE

Back 15

TRUE.

Front 16

Didanosine is unstable in acid conditions. TRUE/FALSE

Back 16

TRUE. It is formulated with a buffer or antacids, and should be taken on an empty stomach.

Front 17

What is Amantadine?

Back 17

It has a narrow spectrum, only inhibiting influenza A. The A is for Amantadine.
Rimantadine is similar, but has fewer CNS side effects.

Front 18

What are neuroaminadase inhibitors?

Back 18

They have clinical activity against both influenza A/B. They target neuraminadase which is responsible for cleaving the bonds between emerging virus and the cell and therefore freeing the virus to penetrate respiratory secretions and replicate.

Front 19

Name 2 neuroaminadase inhibitors.

Back 19

1. Oseltamivir- used for flu prophylaxis.
2. Zanamivir- available as intranasal spray and oral inhaler. Nose bleeds are an uncommon side effect.

Front 20

What is Interferon?

Back 20

These are cytokines that promote a cellular anti viral state.
Interferon alpha has been used to treat hepatitis C and B infection.
If these substances are discontinued, relapses are quite common.