I read in this related article on some ways the borage leaves can be used.
http://www.wikihow.com/Grow-This blog below says that the Indian borage is used as a cough remedy too.
"The leaves can also be used. Some ideas for use include:
"In Singapore, the Indian Borage is often mistakened as a type of mint. To make things worse, a rough search using the Internet search engine will yield has several confusing common names. Botanically, the Indian Borage is known as Plectranthus amboinicus and is a member of Lamiaceae and this herb is famed for its use as a cough remedy."