Oleander: Applications, Treatments, Health Benefits

Oleander embodies for many plant lovers a Mediterranean piece of earth in the home garden. Because of its fragrance and beautiful flowers, it is known to plant lovers as rose laurel. All parts of the plant are poisonous and in larger quantities also deadly to humans.

Occurrence and cultivation of oleander

The flowers are white, yellow or pink depending on the cultivation. A pod-like capsule fruit forms from the flowers. The plant with the botanical name Nerium oleander is the only one of the genus Nerium and belongs to the family of dogwoods. Its homeland is the Mediterranean region. In countries such as Morocco or Spain, it grows both wild and in cultivated form as an ornamental plant. In Asia and the Caribbean islands, there is also the yellow oleander, but despite the name, it is a separate species. The genus name Nerium, which is Latin for wet, is derived from the preferred location of the oleander. It grows as a wild plant near watercourses. It can grow up to five meters tall in the form of a shrub or tree. The leaves are dark green, leathery, elongated and pointed. The flowering period is from mid-June to September. The different cultivated varieties offer different flower colors and different flower shapes such as single, double or double flowers. The flowers are white, yellow or pink depending on the cultivar. A pod-like capsule fruit forms from the flowers. The plant is evergreen and frost sensitive due to the warm latitudes in which it is native.

Effect and application

Oleander is mainly used as an ornamental plant. There are now up to 160 varieties available as container plants or garden plants. It has been used as a garden plant in Europe since the 19th century. In early Arabic medicine, doctors used it as a medicinal plant to fight snakebites. In India, yellow oleander is considered a remedy for skin diseases such as scabies or hemorrhoids. The healing power of the plant and its ingredients is also known in Europe. It contains glycosides, flavonoids, tannins and resin. Of the ingredients, the poison oleandrin is the most significant. It belongs to the cardiac glycosides. Oleandrin acts similarly to digitalis on the heart and circulation. It affects the contractility and beating rate of the heart as a poison with negative consequences and as a medicine with positive consequences. Its use as a remedy for heart failure is considered obsolete in conventional medicine because its effectiveness is weaker compared to other remedies. More rarely, there are still prescription drugs that contain oleander and are against heart failure. Even in modern times, herbalists discouraged the use of parts of the plant as a therapeutic agent. The medicine made from the plant, called Oleandri folium, comes from the crushed and dried leaves. Homeopathy uses drops or globules with oleander as an ingredient in the treatment of cardiac insufficiency and certain forms of cardiac rhythm disorders. The effectiveness of the poison led to its use in abortions or poisoned arrows in the Middle Ages. Even today, a home remedy against mice is to dry the leaves, crush them and sprinkle them mixed with sand in the holes. The beautiful fragrance of the flowers is used in the cosmetic field. The flower essences can be found in certain perfumes or soaps. The extract is also found in some creams under the name Nerium Oleander Extract, as it is said to be skin nourishing.

Importance for health, treatment and prevention.

Rose laurel in its beauty is also dangerous: the poison can be fatal to humans and animals. Animals instinctively avoid this plant. It is deadly to sheep from as little as one gram, and to cats from as little as 0.3 milligrams. For humans, fifteen grams of fresh leaves can be fatal. Although all parts of the plant are poisonous, the leaves contain the most poison. The content is said to be highest during the flowering period. However, it is unlikely that a person would ingest such a high amount unintentionally, as the taste is very bitter. Poisoning leads to nausea and cramps, and in the worst case ends with cardiac arrest. Caution is advisable, especially when gardening. The leaves secrete a milky sap that can cause skin irritation and through open wounds the skin can absorb the poison.Therefore, it is recommended to wear gloves when pruning the plant. In homeopathy, it is customary to use active ingredients in large dilutions. In connection with oleander preparations homeopaths recommend prior consultation and recommendation of the attending physician. In addition to strengthening the heart, this alternative medicine also uses oleander for digestive problems and skin problems. The preparations relieve eczema or rashes on the ear. Also with certain paralyses at arms or legs the plant active substance could be helpful. The plant’s ingredients are diuretic, expectorant and diaphoretic. In minimal doses, they can also strengthen the immune system. Conventional medicine, on the other hand, investigated the plant’s ingredients in terms of their effectiveness against cancer. In clinical tests, it had been shown that an extract induces cancer cells to initiate cell death. Oleander was already known as a remedy against cancer during the Middle Ages in Egypt, India and other countries. Further studies in the U.S. are investigating the extract’s applicability as an anticancer agent. Results have not yet been published.