How Do Antiviral Drugs Work?

Viral infection is caused due to the attack of viruses, which are present in various types. The symptoms of viral infection vary greatly depending on the type of virus causing the infection and its action. The treatment of viral infection depends on the way in which the virus attacks the body, its spread and progress. Know the mechanism of action of anti-viral medication or how do antiviral drugs work to better understand the treatment options.

Here are some ways in which the anti-viral drugs act on the viral infections.

Neuroamidase Inhibitor- How Does it Work in Treating Viral Infection?

Viral infection triggers the secretion of enzyme neuroamidase by the infected cells. This enzyme helps to release the newly formed virus particles attached to cell wall. Thus it helps in multiplication of the viruses and further spreads the infection in the body.

The antiviral drugs that blocks or inhibits the action of neuroamidase are known as neuroamidase inhibitors. The mechanism of action of anti-viral drug, neuroamidase inhibitors is blocking the action of this enzyme. This prevents multiplication and thus restricts the spread of infection. Thus neuroamidase inhibitors are also prescribed as preventive medications. Most common neuroamidase inhibitors prescribed are Zanamvir and Oseltamivir.
How Does Target Cell Blocker Work in Treating Viral Infection?

Target cell blocker are the antiviral drugs that block the entry of virus within the cells and bind within the cell wall. The mechanism of action of this anti-viral medication is directly on the target cells. Viruses are unable to multiply because of lack of cellular amino acids. This group of antiviral drugs helps to prevent release of viruses and prevents rapid spread.

Following Are The Various Types Of Target Cell Blockers-
1. Surface Receptor Blocker- Selective antiviral medications are effective in blocking the entry of virus in target cells. These medications prevent binding of target cell surface receptors. The most common agents prescribed are anti-ideotypical antibodies, natural ligand and anti-receptor antibodies.
2. Entry Inhibitors- The antiviral drugs such as Fuzeon prevent entry of virus within cytoplasm of the target cells.
3. Uncoating Inhibitor- Amantidine and rimantadine, controls uncoating process. These are effective against rhinovirus (common cold), enteroviruses (meningitis, conjunctivitis and encephalitis). It is also effective against respiratory syncytial virus, parainfluenza virus and adenovirus.
How do Cytoplasmic Inhibitors Work in Treating Viral Infection?

The viruses rapidly multiply within cells by breaking the amino acids within chromosomes and sequencing to form the new viruses. Viruses alter the physiological sequence of intracellular amino acid and use the chain of amino acids to form new viruses. The mechanism of action of this anti-viral medication or the way cytoplasmic inhibitor works is blocking the multiplication of virus within target cell at various stages.

There are several cytoplasmic inhibiting antiviral medications acting at various stages of viral multiplication.
1. Reverse Transcription Inhibition- Acyclovir (against herpes virus) and zidovudine (against HIV virus), Lamivudine (hepatitis B), inhibits and deactivates enzymes which trigger synthesize of RNA and DNA.
2. Integrase Inhibition- Integrase inhibitor antiviral medications block DNA synthesis. The medications prevent spread of DNA viruses.
3. Transcription Factor Inhibitors- Viruses that once enter into cytoplasm result in increased secretion of messenger RNA. The messenger RNA triggers secretion of transcription factor. Transcription factor is a protein molecule, which initiates production of RNA and DNA within target cells. Transcription factor inhibitor blocks transcription factor and prevents production of RNA and DNA amino acid sequence, resulting in restriction or stoppage of multiplication of viruses within cytoplasm of target cells.
4. Translation Antisense Inhibitors- Antiviral drugs or medications like Caliciviruses, Flaviviruses and Coronaviruses trigger secretion of DNA and RNA molecule. These RNA and DNA molecules inhibit the rapid multiplication of virus and known as antisense inhibitors.
How Does Antiviral Ribozymes Work in Treating Viral Infections?

The recent research studies suggest some of the antiviral ribozymes are capable of breaking the virus RNA and DNA chains. The breaking of viral RNA and DNA sequence leads to dysfunctional virus particle. Ribozymes are enzymes capable of breaking RNA and DNA amino acid sequence. The mechanism of action of antiviral preparation of ribozymes has been found effective against hepatitis C and HIV infection.
Protein Processing and Targeting

The mechanism of action of antiviral drugs or medications may also target the protein in the virus, thus controlling its multiplication. Some antiviral drugs are targeted to change the sequence of amino acids once the virus particles are formed within the cell cytoplasm. The change of viral DNA and RNA amino acid sequence causes inactive virus or protein particles.
Protease Inhibitors

Most viruses form enzyme protease, which assembles the amino acids to form the final viral RNA or DNA molecules. The recent studies suggest that there are antiviral drugs, which can block the protease enzyme resulting in dysfunctional viral amino acid chain. The outcome of treatment causes restricted spread of infection.
Improved Immunity

The few selective white blood cells target viruses and destroy the viral particles. If the viruses are rapidly multiplying and number of active white blood cells are less in numbers, then the infection rapidly spreads to other organs and target cells. Increased immunity is the physiological resistance build within an individual to protect from any infection. The individual with better immunity has an increased number of active white blood cells that can destroy the viruses rapidly.

Immunity also improves the efficiency of white blood cells against the virus particles. With better immunity, more and more white blood cells are formed, which act against the viral infection. This can be achieved by treating with antibodies. In some cases, the mechanism of action of anti-viral medications is to increase antibodies and build stronger immunity. Antibodies attract white blood cells, which adhere to viral RNA or DNA molecules and cause destruction of virus particles. Susceptible elderly adults or children are treated with antibody injection. Antibodies are frequently used against hepatitis B and respiratory syncytial virus infection.

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How Do Antiviral Drugs Work?