Antiviral And Antifungal Drugs

Front 1

What are viruses?

Back 1

obligate intracellular parasites that require the active participation of the metabolic processes of the host to survive.

Front 2

Describe a virus. (3)

Back 2

1. Smallest infectious agent
2. Consist of nucleic acid enclosed in a protein coat.(nucleocapsid)
3. Whole infective particle is termed a virion.

Front 3

Name and describe the 2 major virus types.

Back 3

DNA viruses: enter host cell nucleus and direct the generation of new viruses. ex:smallpox, herpes, papilloma virus.
RNA Viruses: direct the generation of new viruses without involving the host's nucleus. Copy of DNA made from RNA-reverse transcriptase. ex: influenza, measles, mumps, rubella, retroviruses(AIDS).

Front 4

What are the 3 mechanisms by which antiviral drugs work?

Back 4

1. Inhibiting nuceic acid synthesis
2. Inhibiting attachment to or penetration of host cells.
3. Immunomodulation(supress growth)

Front 5

Which antiviral drugs act as inhibitors of nucleic acid synthesis(4)?

Back 5

1. acyclovir
2. vidarabine
3. ribavirin
4. zidovudine(AZT)

Front 6

What are the general characteristics of the prototype acyclovir(3)?

Back 6

1. prevents viral DNA replication
2. Looks like a DNA base so it integrates into DNA and breaks up virus.
3. High affinity for viral DNA polymerase compared to human cells. Specific to virus.

Front 7

What are the uses(3) and side effects of acyclovir(4)?

Back 7

uses:
1. herpes simplex infections
2. Varicella-zoster infections(shingles)
3. Chicken pox in immunocompromised patients.
side effects:
1. GI disorders
2. Headache, fatigue and hair loss
3. Nephrotoxicity
4. Encephalopathy(rare)

Front 8

How does AZT work?

Back 8

inhibits reverse transcriptase

Front 9

What is AZT used for and what are the SE of it(3)?

Back 9

use: AIDS
Side effects:
1. Hematolgic toxicity
2. Neurotoxicity
3. Damages bone marrow

Front 10

What antiviral drugs are inhibitors of viral penetration of host cells(2)?

Back 10

1. amantadine
2. gamma globulin

Front 11

How does amantadine work? What are the side effects?

Back 11

Blocks the pentration of influenza A virus into host cells.
side effects:
CNS: confusion, hallucination, seizures, and coma.

Front 12

Describe the use of gamma globulin.

Back 12

It is a non-specific treatment for short term defense against viral infections.

Front 13

What are the general characterstics of the immunomodulators(3)?

Back 13

1. naturally occuring glycoproteins produced by mammilian cells.
2. involved in immune functions
3. produce enzymes that inhibit the translation of viral mRNA into viral proteins.

Front 14

What are the two groups of interferons?

Back 14

alpha, beta

Front 15

What are the uses(4) and side effects of interferons(2)?

Back 15

uses for alpha:
1. AIDS related bone cancer
2. Hepatitis C infection
3. Cancer
uses for beta:
1. MS
Side effects:
1. flu like symptoms
2. bone marrow suppression

Front 16

What are diseases caused by fungal infections called and give a general description of them?

Back 16

1. mycoses
2. Often chronic in nature
3. more difficult to treat than bacterial infections because of the tissues they target(poorly vascularized)skin, nails, and hair.

Front 17

Name and describe the two types of fungal infections.

Back 17

1. Superficial: skin, scalp, or mucus membranes.
2. Systemic: infect internal organs and tissues such as the lungs or blood. Often life threatening and difficult to treat.

Front 18

What are the five antifungal drug classes?

Back 18

1. Polyene macrolides: Amphotericin B, Nystatin
2. Imidazoles: ketoconazole, miconazole
3. Pyrimidines: Flucytosine
4. Allylamine: Terbinafine(lamasil)
5. Misc. Agents: Griseofulvin

Front 19

What are the general characteristics of Amphotericin B(3)?

Back 19

1. MOA: interfers with permeability and transport functions of fungal cell membranes.
2. Binds specifically to ergosterol(fungal membrane sterol)
3. broad spectrum

Front 20

What is Amphotericin B used for and list its side effects(4)?

Back 20

uses: life threatening systemic fungal infections.
side effects:
1. hypersensitivity
2. renal toxicity
3. fever, chills, headache
4. anemia

Front 21

What are the uses(2) and side effects(3) of Ketoconazole?

Back 21

uses:
1. systemic infections
2. topical eye infections
side effects:
1. hypersensitivity
2. hepatotoxicity
3. gynecomastia

Front 22

What are the general characteristics of Grisefulvin(2)?

Back 22

1. MOA: inhibits fungal cell mitosis
2. binds to microtubules and interferes with spindle formation in dividing cells leading to inhibtion.

Front 23

What are the uses and side effects(4) of Griseofulvin?

Back 23

use: fungal diseases of the skin(athlete's foot, ring worm)
side effects:
1. allergic reaction
2. GI disorders
3. headache
4. photosensitivity

Front 24

What are the major concerns for PT with patients using antifungal drugs(3)?

Back 24

1. Very likely to encounter these patients.
2. Patients will often be weak or debilitated with life threatening infections
3. Must observe isolation levels and take precautions to protect yourself and the patient.