It is common for patients to have poor mental health, weakness and lethargy, mostly due to some influenza viruses and parainfluenza viruses. When the body is feverish, the blood circulation is accelerated and a large amount of energy can be consumed, which leads to general weakness and is a normal phenomenon. Patients are advised to drink more fluids during the fever and seek medical attention if necessary. In addition, some common cold medications have anti-allergic and anti-fever components, which can have these complications of drowsiness, and also the side effects of these medications can cause us to be weak and drowsy.