Goodbye Dry January, hello hangover Updated / Wednesday, 30 Jan 2019 09:32 Opinion: as Dry January ends, some advice and myth-busting about how best to avoid hangovers For something that happens to so many people so often, the clinical understanding of the hangover is quite limited. The symptoms are well-known: a dark constellation of unpleasantness and misery including fatigue, headache, increased sensitivity to light and sound, redness of the eyes, muscle aches, thirst, nausea, vomiting, dizziness, and sometimes depression, anxiety and irritability. Quite the cocktail. The root of some of these symptoms is clear enough. For example, alcohol promotes the production of urine, thus causing dehydration and thirst. Alcohol also directly irritates the lining of the stomach, causing nausea and vomiting. On a stranger note, alcohol disrupts our circadian rhythm, the "inner clock" of our body which carries out activities depending on the time of the day; as a consequence of this, having a hangover can be similar to suffering from jetlag and vice-versa.