NatureScot and Care of Burns in Scotland Managed Clinical Network (COBIS) issued the warning ahead of the school summer holidays, when people, particularly children, are most likely to be exploring the outdoors.
Giant hogweed sap contains a toxic chemical, which sensitises the skin to sunlight and causes severe blisters, resulting in burns which can be serious and long lasting.
Every year gardeners, walkers, children and animals are hurt by the plant.
Not native to Scotland, giant hogweed is widespread across central and eastern parts of the country.
It is commonly found along river banks, on waste ground and beside roads and train tracks.
NatureScot’s Invasive Species Policy Manager Stan Whitaker said: “It’s really important for people to be able to recognise giant hogweed so they can avoid potentially serious injury.
“Thankfully the plant is relatively easy to identify when fully grown due to its enormous size of between two and four metres tall, with large white clusters of flowers up to 80 centimetres wide.
“Its leaves are very large and sharply divided and can be over one metre across while the stems are green with purple blotches and covered with bristly hairs.”
Eleanor Robertson, Senior Clinical Research Fellow at NHS Greater Glasgow and Clyde said:
“This plant, although impressive to look at, is best avoided and reported to your local council. If you do come in to contact with the plant, you must cover the affected area to block sunlight then thoroughly wash the area to remove the sap. Should redness or blistering occur, you should seek medical help.”
Mr Whitaker continued:
“As well as being a health risk to people and animals, giant hogweed is also a risk to our environment because it forms dense patches which crowd out our native plants.
“It can be very tricky to eradicate, because each plant produces over 20,000 seeds, which can live in the soil for up to five years, so land owners need to take a long-term approach to removing it every year, before it flowers.”
Dog walkers are also being urged to keep their pets away from giant hogweed, as it is harmful to animals as well as humans.
Anyone who spots giant hogweed growing on amenity land, such as parks, playing fields, footpaths or road verges, should report it to the local authority.