Anti Microbial Agents contains Antiviral Drugs

1. Antiviral Drugs
Dr. Saroj K. Suwal

2. Anti Viral Medicine
 Drug used for Viral Infections by
Virus
 Antiviral drugs don’t' kill the
Pathogen rather it inhibits its growth
mainly
Viruses are difficult to Kill ?
Why
to kill because they live
inside the cells (
obligate Parasites),
So, Any drug that kills a
virus may also kill cells

3. Common viral infections
 Cytomegalovirus (CMV)
 Hepatitis viruses
 Herpes viruses
 Human immunodeficiency virus
(HIV)
 Influenza viruses (the “flu”)
 Respiratory syncytial virus
(RSV)→ SARS, COVID

4. Respiratory Viruses
 Most Common Virus
infection
 DNA and RNA virus

5. Viruses
 have no cell wall and made up of nucleic acid
components
 contain envelope – antigenic in nature
 Viruses are obligate intracellular parasite •
 They do not have own metabolic machinery– uses
host enzymes
 virus cannot replicate on its own , It must attach to
and enter a host cell It then uses the host cell’s
energy to synthesize protein, DNA, and RNA

6. Antiviral Drugs Classifications
 Drugs classification as follows
Antiviral drugs
Anti retroviral drugs
Herpes Simplex Virus
Varicella zoster virus

10. Antiviral spectrum :
 Acyclovir: HSV-1, HSV-2, VZV, Shingles.
 Ganciclovir / Cidofovir : CMV
 • Famciclovir : Herpes genitalis and shingles
 • Foscarnet : HSV, VZV, CMV, HIV
 • Penciclovir : Herpes labialis
 • Trifluridine : Herpetic keratoconjunctivitis

11. Acyclovir
 Antiviral drug
 decrease pain and speed the healing of sores or blisters
 MOA
Interferes with viral DNA synthesis
Inhibit viral replications
Decrease viral shedding

12. Clinical Use

13. Preparations
 Capsule: 200mg
 Tablet: 200mg, 400mg, 800 mg
 Injection: 250mg, 500mg in vail
 Cream : 5 % in 2gm
 Ointment:5 % in 3 and 15 gm

14. Acute herpes zoster:
 800 mg orally every 4 hours (5 times
a day) for 7 to 10 days Severe,
immunocompromised host: 10
mg/kg /BW IV every 8 hours for 7 to
14 days should be initiated within 72 hours after onset of rash,
although, during clinical trials, acyclovir was most
effective when initiated within the first 48 hours.

15. For Varicella-Zoster& Chickenpox:
 Not immunocompramised:800 mg POX ODX 5 days
 Immunocompromised host: 10 mg/kg IV every 8 hours for 7 to 10
days or until no new lesions for 48 hours;
 After fever stops, if there is no proof of visceral involvement, the
patient may be switched to 800 mg orally four times a day
Therapy should be initiated at the earliest sign of chickenpox,
no later than 24 hours after onset of rash.

16. Side effects
 CNS→ seizure, headache, dizziness, hallucinations, tremling
 GI→ diarrhea, nausea, vomit, abdominal pain, anorexia
 GU→ renal failure, crystalluria, hematuria
 Derma→ acne, skin rashes, unusual sweat
 Hemato→ thrombocytopenia, purpura, hemolytic uremic syndrome
 Myelosuppression – Neutropenia and thrombocytopenia
 Local→ pain , phlebitis, local irritation,

17. Nursing Management
 Give with intermittent IV infusion
 Add 5ml sterile water for injection in every
250mg vial , 10 ml for 500mg
 Further diluted with NS or DNS
 Shake well before giving
 Maintained hydrations
 Input output charting and w/f crystalluria

18. ART-Anti Retroviral Therapy
 Combination Therapy
 For HIV
 HAART-Highly active
antiretroviral therapy
 Includes at least
three medications

19. ART Drugs
 Protease Inhibitors