The surface of the plant is covered in a mix of chemicals including
psoralen,
xanthotoxin and
bergapten that causes a
phototoxic reaction resulting in blistering two or three days after exposure. The moment of exposure is innocuous, without any untoward sensations to the unwary. Exposure of the affected skin to
ultraviolet light, such as contained in sunlight, triggers the effects of the plant's toxins, leading to severe itching and blistering. The welts and resulting blisters can be as small as the size of a coin to covering as much exposed skin as came into contact with the plant. Where more than 5% of the body is afflicted, the scarring can be a serious matter. Washing the affected area immediately after exposure may help but preventing any further exposure to ultraviolet light such as the sun or many artificial light sources will reduce and /or eliminate blistering.
Medicinal uses Surprisingly, considering its toxicity, it has been credited with a range of medicinal properties. In the traditional medicine of the indigenous peoples of the Cape, it has been recorded as a diuretic and as a treatment for rheumatism, gout, bladder ailments, water retention and high blood pressure. The medicinal application of the plant's foliage took the form of an infusion. == Cultivation ==