Viral Infection - Chapter 30 Flashcards
Virus
- An intracellular parasite that consists of a DNA or RNA core surrounded by a protein coat
- Virions must use their host’s cellular machinery to replicate
Examples of Viral Infections
- Common cold
- Warts
- HIV
- Smallpox, measles, mumps, rubella
- Hepatitis A, B, and C virus
- HPV
- EBV
- Rotavirus
- Norovirus
Antivirals MOA
- Inhibit replication
- Antivirals are virostatic; they do not destroy viruses
- Slow the rate of virus proliferation spo the immune system can fight the infection
Factors That Influence the Outcome of Antiviral Therapy
- Stage of illness at the time of initiation of therapy
- dosage of antiviral agent used
- Ability of the virus to penetrate the CNS
- Ability of the virus to remain latent within its host
- Development of antiviral resistance
Antiviral Tech Note
- Antivirals are only effective against specific ciruses
- Antibiotics are not effective against viral infections
Antiviral Resistance
-The ability of a virus to overcome the suppressive action of antiviral agents
May occur when:
- Antiviral drugs are taken irregularly or doses are skipped
- Subtherapeutic levels are received due to vomiting
- Drug levels are too low to suppress viral replication
- There is natural viral mutation
Treatment and Prevention of Influenza
- amantadine
- oseltamivir
- zanamifir
Generic: amantadine
amantadine
- For prevention and treatment of Influenza A only
- Inhibitor of viral uncoating
- Lots of resistance
Warning Labels: MAY CAUSE DIZZINESS OR DROWSINESS
amantadine ADR’s
- anxiety
- Irritability and nervousness
- Drowsiness or insomnia
- Confusion
- Headache
- Diarrhea or constipation
- Nausea/vomiting
Generic: oseltamivir
Tamiflu
- for treatment of Influenza A and B
- Neuraminidase inhibitor
- Must be started within 48 hours of symptom onset to be effective
Warning Labels:
- TAKE WITH FOOD
- REFRIGERATE, SHAKE WELL, DISCARD AFTER 10 DAYS (suspension)
Generic: zanamivir
Relenza
- For treatment of Influenza A and B
- Neuraminidase inhibitor
- Must be started within 48 hours of symptom onset to be effective
Specific ADR’s:
- Bronchospasms in people with asthma
- Contraindicated in pregnancy
Warning Labels:
-INHALE USING DISCHALER DELIVERY DEVICE
oseltamivir and zanamivir ADR’s
- Coughing
- Difficulty Sleeping
- Dizziness
- Headache
- Nausea/vomiting
- Psychosis
- Neural complications
Drugs Used to Treat Influenza: Warning Labels
-COMPLETE FULL COURSE OF THERAPY
Treatment of Hepatitis B and C Viruses: Interferons
-Inhibitors of Transcription
- interferon alfa-2b
- peginterferon alfa 2-a
- peginterferon alfa 2-b (+ribavarin)
Generic: interferon alfa-2b
Intron A
- Interferon
- For treatment of Hepatitis B
- Must be refrigerated
Generic: peginterferon alfa-2a
Pegasys
- Interferon
- For treatment of Hepatitis B
- Must be refigerated
Generic: peginterferon alfa-2b (+ribavarin)
Pegitron
- Interferon
- For treatment of Hepatitis C
- Must be refigerated
Interferons ADR’s
- Fever/chills
- Headache
- Fatigue
- Muscle aches/Joint pain
- Nausea/vomiting
- Diarrhea
- Dizziness
- Depression
- Serious drop in white blood cells and platelets
Treatment of Hepatitis B and C Viruses: Nucleoside Analogs
-Inhibitors of Transcription
- entecavir
- lamivudine
- ribavirin
- telbivudine
Generic: entecavir
Baraclude
- Nucleoside Analog
- Used to treat Hepatitis B
-Warning Labels: TAKE ON EMPTY STOMACH
Generic: lamivudine
Heptovir
- Nucleoside analog
- Used to treat Hepatitis B
-Warning Labels: TAKE WITH OR WITHOUT FOOD
Generic: ribavirin
Virazole
- Nucleoside analog
- Used to treat Hepatitis C
Warning Labels: TAKE WITH FOOD
Generic: telbivudine
Sebivo
- Nucleoside analog
- Used to treat Hepatitis B
Warning Labels: TAKE WITH OR WITHOUT FOOD
Treatment of Hepatitis B and C Viruses: Nucleotide Analogs
- Inhibitors of transcription
- adefovir
Generic: adefovir
Hepsera
- Nucleotide analog
- Used to treat Hepatitis B
Treatment of Hepatitis B and C Viruses: Protease Inhibitors
-Inhibitors of transcription
- boceprevir
- telaprevir
Generic: boceprivir
Victrelis Triple
- Protease inhibitor
- Used to treat Hepatitis B and C
Generic: telaprevir
Incivek
- Protease inhibitor
- Used to treat Hepatitis B and C
Treatment of Herpes: Inhibition of DNA and RNA Replication
Common Ending: “cyclovir” or “ciclovir.”
-Antivirals that inhibit DNA and RNA replication are used to treat: -herpes simples type 1 and 2 -herpes zoster -varicella zoster -cytomegalovirus (CMV) -respiratory syncytial virus (RSV)
Generic: acyclovir
Zovirax
- Inhibits DNA and RNA replication
- Used to treat Herpes Simplex Type 1 and 2 and Varicella Zoster
Warning Labels: SHAKE WELL (suspension)
Generic: famciclovir
Famvir
- Inhibits DNA and RNA replication
- Used to treat Herpes Simplex type 1 and 2, and acute Herpes Zoster infections
Generic: ganciclovir
Cytovene
- Inhibits DNA and RNA replication
- Used to treat CMV
Warning Labels:
- AVOID PREGNANCY
- TAKE WITH FOOD
- SWALLOW WHOLE; DONT CRUSH OR CHEW
Generic: valacyclovir
Valtrex
- Inhibits DNA and RNA replication
- Used to treat Herpes Simplex Type 1 and 2 and Varicella Zoster
Generic: valganciclovir
Valcyte
- Inhibits DNA and RNA replication
- Used to treat CMV
Generic: trifluridine
Viroptic
Warning Labels:
- REMOVE CONTACT LENSES BEFORE USE
- REFRIGERATE
Herpes Treatment Drugs ADR’s
- Diarrhea
- Nausea/vomiting
- Headache
- Fatigue
- Dizziness
- Confusion
Herpes Treatment Drugs Warning Labels
- COMPLETE FULL COURSE OF THERAPY
- PROTECT FROM LIGHT AND MOISTURE
HIV
- Virus that attacks the immune system, resulting in a chronic, progressive illness that leaves people vulnerable to infections
- Attacks CD4 T-lymphocytes
- When the body can no longer fight the infection, the disease has become AIDS
Antiretrovirals
Medicines that interfere with replication of retroviruses
- Reduce viral load
- Increase CD4 counts
- Delay development of AIDS-related conditions
- Improve survival
Reducing Antiretroviral Resistance: Highly Active Antiretroviral Therapy (HAART)
-A combination of 3 or more medications in a regimen or AIDS “cocktails” is prescribed
Generic: zidovudine
Retrovir (AZT)
-decreases perinatal mother-to-child transmission of HIV
Warning Labels:
- TAKE EXACTLY AS DIRECTED; DONT SKIP DOSES
- TAKE WITH LOTS OF WATER
- REFRIGERATE DILUTED SOLUTION: DISCARD AFTER 48 HOURS
