Typically it lasts 7 to 14 days, but can be as short as a few days or as long as 4 to 6 weeks. Severe digestive disturbances such as loss of appetite, nausea, vomiting and diarrhoea are common, and in severe cases, gastrointestinal bleeding may occur. Respiratory distress, coughing and breath-holding chest pain may also occur. The circulatory system manifests itself in water and sodium retention due to low urination, hypertension, heart failure, electrolyte disturbances and cardiac arrhythmias. Meanwhile, the nervous system may show symptoms of uremic encephalopathy such as agitation, delirium, convulsions and coma, while infection is the most common and serious complication during the oliguric phase.