Why isn't acyclovir used to treat viral infections other than herpes simplex!
Question: Acyclovir is used to treat herpes and sometimes HIV, oral hairy leukoplakia, or epstein-barr. Why isn't it effective against the common cold or other viruses? Also, does it need to be taken persistently and long-term to combat viral outbreaks, or only for 7-14 days?
I'm curious from a medical perspective (I'm not a patient), so feel free to be technical in your reply.
Answers: Acyclovir is used to treat herpes and sometimes HIV, oral hairy leukoplakia, or epstein-barr. Why isn't it effective against the common cold or other viruses? Also, does it need to be taken persistently and long-term to combat viral outbreaks, or only for 7-14 days?
I'm curious from a medical perspective (I'm not a patient), so feel free to be technical in your reply.
Just like with antibiotics that are active against bacteria in different ways (mechanisms of action), antiviral medications also target different mechanisms -- usually the reproduction cycle.
The two main requirements for medication choices:
- the process that it prevents/interupts must be an integral process of viral replication
-the agent/drug is active against the virus while having an acceptable toxicity to the host organism.
The antiviral drugs are made up of different chemicals (nucleoside analogs that can target viral polymerase and in some cases reverse transcriptase; peptide analogues that target HIV protease; Triazole carboxamide, which mutates RNA, eg. ribavirin -- broad spectrum as it works on HCV, HSV, measles, mumps, Lassa fever etc.; tricyclic amines that target surface structural proteins; neuraminic acid mimetic that targets the neuraminic inhibitor; small cyclic chemicals that block attachment and uncoating; and proteins that target the activation of cell defense proteins.
Attachment, Penetration/Uncoating, Genome replication, Gene Expression, and Assembly/Maturation/Release are the main targets in the viral replication cycle that agents target.
Every virus is different and some drugs are simply more effective against certain viruses and less against others. It may have to do with the particulars of the viral replication cycle, makeup of the virus' coat, etc.,.
The duration of antiviral treatment is different for most viral infections and can depend on the virus in question, host factors (compromised immune system etc.), stage of disease/viral load, as well as other co-conditions.
Hope this helps