Institute first-aid kit found on a 2000-year-old shipwreck has provided a remarkable insight into the medicines concocted by ancient physicians to cure sailors of dysentery and other ailments.
Medicines found inside a wooden chest included pills made of ground-up vegetables, herbs and plants such as celery, onions, carrots, cabbage, alfalfa and chestnuts - all ingredients referred to in classical medical texts.
The tablets, which have miraculously survived being under water for more than two millennia, also contain extracts of parsley, nasturtium, radish, yarrow and hibiscus.
They were found in 136 tin-lined wooden vials on a 15m-long trading ship which was wrecked about 130BC off the coast of Tuscany.
Scientists believe they would have been used to treat gastrointestinal complaints suffered by sailors such as dysentery and diarrhoea.
"It's a spectacular find. They were very well sealed," said Dr Alain Touwaide, from the Smithsonian Conservation Biology Institute in Washington DC.
"The plants and vegetables were probably crushed with a mortar and pestle - we could still see the fibres in the tablets. They also contained clay, which even today is used to treat gastrointestinal problems."
The pills are the oldest-known archaeological remains of ancient pharmaceuticals.
They would have been taken with a mouthful of wine or water, or may have been dissolved and smeared on skin to treat inflammation and cuts.