Yes, alcoholism can cause mood swings. Alcohol is a depressant that affects the central nervous system, which can lead to changes in mood, behavior, and emotional responses. In the short term, alcohol can initially make people feel more relaxed and less inhibited, but over time, excessive drinking can lead to mood swings and even mental health issues such as depression and anxiety. Additionally, alcohol can cause changes in brain chemistry that can contribute to mood swings and other emotional issues.