Viruses can cause damage to the body after they invade the body, and antiviral drugs are drugs that remove the virus or inhibit virus replication, of which ribavirin is a broad-spectrum antiviral drug. There are also many drugs for different viruses, for example, for the hepatitis B virus there are antiviral drugs such as entecavir, tenofovir, lamivudine, adefovir, and tebivudine. For hepatitis C there can be antiviral drugs such as interferon, and for AIDS there are antiviral drugs such as ekprevir, and the mechanism of action of different drugs is different.