People from other countries brought this plant to Hawaii. It is a weed now, growing where it is wet. At one time, the Hawaiians gathered a cousin of this plant from wet spots in the forest to use for medicine, now people use the weed because it is easier to get.

The ancient Hawaiians used the leaves of the lau-kahi for medicine for three kinds of sickness:

As a tonic, when one felt weak
To give one regular bowel movements
For boils

1) When it was given to make people feel stronger, especially children, the fresh leaves were baked in ki (ti leaves) and then chewed by the mother before she gave them to the child to swallow. Different numbers of leaves were given for very young and older children:

A child 10 days old, 1 leaf
A child 20 to 40 days old, 1&1/2 leaves
A child 50 days to 3 months old, 2 leaves
A child 4 to 6 month5 old, 3 leaves
A child 7 months to 1 year old, 4 leaves

2) For grown-ups, 4 or 5 leaves (green or dried) were eaten to have regular bowel movements,

3) For a large boil, 2 green leaves were rubbed together with some salt until they were soft. Then this was put on top of the boil to cover the whole lump. A narrow piece of tapa or other cloth was made into a ring and this was put on and around the eye of the boil and tied on with a bandage made from a piece of tapa or cloth. Every morning, fresh lau-kahi was put on the boil until it broke open and the core came out.