Levels of vomiting, diarrhoea and gastroenteritis all dropped in Southwark last week, GP records show.
Weekly data from Public Health England shows that GPs in Southwark reported seeing 48 patients with diarrhoea between May 6 and 12.
It was a decrease from 73 patients in the previous week, and meant that 30.4 patients in every 100,000 registered with GPs were seen with the illness over the seven-day period.
Not all cases were recorded in the PHE figures, as only some GPs report how many consultations are for certain illnesses. The rates per population that PHE calculates takes this into account.
The decrease was reflected across the whole of London, where 24% fewer people were seen with diarrhoea last week.
People with diarrhoea are advised to stay off work until the symptoms have stopped for at least two days. The NHS says it normally passes in five to seven days.
Levels of diarrhoea in Southwark were 22% lower than expected last week, when compared to the national average.
Southwark historically has low levels of diarrhoea, with longer-term trends showing that levels are generally 12% lower than the national average.
Doctors also saw 79 patients with gastroenteritis last week, at a rate of 50.1 patients per 100,000.
It was 51 fewer than during the previous week, and meant that levels were 22% lower than expected.
Gastroenteritis is a common condition, usually caused by a stomach bug. People with the illness are advised against going to see their GP, to help prevent the disease spreading.
Also last week, 22 patients had vomiting symptoms, 27% below expected levels.
Vomiting can be caused by a number of conditions, including norovirus, known as the vomiting bug, and food poisoning. The NHS says it should pass in one or two days.