All of us feel tired from time to time, but for some people, tiredness can be a more serious problem. It may go on for a long time or can be so serious we can’t function properly. A lack of energy can be caused by a variety of different factors: it can follow an illness or an operation, or be a symptom of conditions we find hard to explain such as ME and Seasonal Affective Disorder. Barbara Myers will be joined by consultant neurologist Leslie Findley to answer your questions.