What causes nausea immediately after waking up?
1. Introduction Nausea immediately after waking up is frequently caused by overnight metabolic shifts such as fasting hypoglycemia, nocturnal gastric acid accumulation, or circadian hormonal fluctuations. During sleep, the gastrointestinal tract slows down, and empty stomach acids can irritate the gastric lining, while low blood sugar triggers a compensatory stress response that induces queasiness. Additionally, … Read more