The common cold, or upper respiratory tract infection, is one of the leading reasons for physician visits. Generally caused by viruses, the common cold is treated symptomatically. Antibiotics are not effective in children or adults. In children, there is a potential for harm and no benefits with over-the-counter cough and cold medications; therefore, they should not be used in children younger than four years. Other commonly used medications, such as inhaled corticosteroids, oral prednisolone, and Echinacea, also are ineffective in children. Products that improve symptoms in children include vapor rub, zinc sulfate, Pelargonium sidoides (geranium) extract, and buckwheat honey. Prophylactic probiotics, zinc sulfate, nasal saline irrigation, and the herbal preparation Chizukit reduce the incidence of colds in children. For adults, antihistamines, intranasal corticosteroids, codeine, nasal saline irrigation, Echinacea angustifolia preparations, and steam inhalation are ineffective at relieving cold symptoms. Pseudoephedrine, phenylephrine, inhaled ipratropium, and zinc (acetate or gluconate) modestly reduce the severity and duration of symptoms for adults. Nonsteroidal anti-inflammatory drugs and some herbal preparations, including Echinacea purpurea, improve symptoms in adults. Prophylactic use of garlic may decrease the frequency of colds in adults, but has no effect on duration of symptoms. Hand hygiene reduces the spread of viruses that cause cold illnesses. Prophylactic vitamin C modestly reduces cold symptom duration in adults and children.