It is true that three people cannot take ribavirin. They are pregnant women, people who are allergic to this drug and people who are potentially pregnant. The reason why pregnant women and those who are likely to become pregnant should not take this medicine is that ribavirin is highly teratogenic and is eliminated slowly in the body, potentially causing damage to the embryo (fetus). People who are allergic to this medicine should also not take this medicine as it may cause a severe allergic reaction. Ribavirin is indicated for bronchitis and viral pneumonia caused by respiratory syncytial virus, skin herpes virus infections. This medicine may trigger adverse reactions such as anemia, body weakness, headache and insomnia, mild diarrhea. People with abnormal liver function and severe anemia should use this medicine with caution. As a prescription drug, it must be used under the supervision of a doctor and should not be used at will.