Oleander
Nerium oleander L. Family: Apocynaceae (dogbane)
Oleander , adelfa , laurier rose , rosa laurel , rose bay , rosa francesa . 1
 
Clinical Overview
Uses
Oleander has been used in the treatment of cardiac illness, asthma, diabetes mellitus, corns, scabies, cancer, and epilepsy. However, in none of these conditions is there good evidence for use.

Dosing
There is no clinical evidence to support specific doses of oleander. Extreme caution should be used because of its acute cardiotoxicity.

Contraindications
No longer considered safe.

Pregnancy/Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.

Interactions
None well documented.

Adverse Reactions
Phytodermatitis caused by contact with oleander has been reported frequently.

Toxicology
Oleander is extremely toxic. Major toxicity includes disturbances in heart rhythm and death. Other signs of toxicity include pain in the oral cavity, nausea, emesis, abdominal pain, cramping, and diarrhea.

 
Botany
The oleander is a shrub that grows to about 6 to 7 meters in height. It has long, narrow leaves that attain almost 5 to 12 inches (1 meter) in length, and these are typically grouped in threes around the stem. The red, pink, or white fluffy flowers form in small clusters. Cultivated plants rarely produce fruits. 1 Although native to the Mediterranean, the oleander is widely cultivated throughout warm, tropical climates. Oleander is synonymous with Nerium indicum Mill. Oleander should not be confused with yellow oleander ( Thevetia neriifolia ), a related toxic plant.
 
History
Despite its well-recognized toxic potential, the oleander has been used in traditional medicine for centuries. It was used by primitive people as arrow and dart poisons. 2 Its uses included the management of such diverse ailments as cardiac illnesses, asthma, corns, cancer, and epilepsy. 3
A number of uses for oleander have been reported, although in most cases, evidence supporting these indications is lacking. In the Narni area of Umbria, in the Italian countryside, the farmers and shepherds still use medicinal plants. N. oleander leaves are ground and mixed with honey to form a poultice and then applied topically to treat scabies. 4 In certain regions of Morocco, phytotherapy represents an integral part of health care. Diabetes mellitus, hypertension, and cardiac disorders are conditions treated with oleander. 5
 
Chemistry
The plant contains a number of related cardiac glycosides similar in activity to digitalis. The main glycosides are oleandrin and neriine. 2 Cardenolides gentiobiosyl oleandrin and odoroside also are present. 3 In addition, a variety of other pharmacologically active compounds, including folinerin, rosagenin, rutin, and oleandomycin, have been identified in the plant. 3
 
Uses and Pharmacology
More recently, research has focused on the anticancer effects of oleander and its constituent compounds. Oleandrin inhibits certain kinases, transcription factors, and inflammatory mediators, including tumor necrosis factor. This may provide a molecular basis for the ability of oleandrin to suppress inflammation and perhaps tumorigenesis. The authors of this in vitro study suggest that oleandrin may have applications for various diseases, including arthritis, but all require further investigation. 6
 
Administration & Dosage
There is no clinical evidence to support specific doses of oleander. Extreme caution should be used because of its acute cardiotoxicity.
 
Pregnancy/Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.
 
Interactions
None well documented.
 
Adverse Reactions
Phytodermatitis caused by contact with oleander has been frequently reported. The dermatitis may result when crushed leaves of the shrub come into contact with the skin of a person who is sensitive because of previous exposure. The crushed leaves and stems have been reported to be irritating, but the allergenic properties have not been adequately studied. Generally, no positive patch test can be obtained. 7
 
Toxicology
The entire oleander plant contains toxic cardiac glycosides. However, the highest levels are found in the roots and seeds. Even smoke from the plant and water in which the plant has been immersed can be toxic. 1
In birds, as little as 0.12 to 0.7 g of the plant has caused death. 8 As few as 15 to 20 g of fresh leaves can be fatal to a horse, and 1 to 5 g can be lethal to a sheep. 3 Deaths have been reported in children who ingested a handful of flowers and in adults who used the fresh twigs as meat skewers; the nectar makes honey toxic. 3 , 9 Additionally, oleander reportedly was used in a case of deliberate poisoning by chronic administration of the roots of the plant over an 8-week period. 10
Symptoms of oleander toxicity include pain in the oral cavity, nausea, emesis, abdominal pain, cramping, and diarrhea. Special attention must be given to cardiac function. The cardiac glycosides may induce conduction defects. Most common are defects affecting the sinus or AV nodes with PR interval prolongation and progression to atrioventricular dissociation. 11 Additionally, systemic hyperkalemia induced by the plant may worsen cardiac function. 1
Oleander toxicity should be managed aggressively. Gastric lavage or induced emesis should be performed. Some experts have reported that activated charcoal may be administered orally. ECG monitoring for cardiac impairment and monitoring of serum potassium levels should be performed frequently. 1 The conduction defects can usually be managed with atropine and isoproterenol, which contain similar compounds. 12 Anti-digoxin Fab fragments have been shown to be a safe and effective treatment for serious cardiac arrhythmias induced by yellow oleander. Administration of anti-digoxin antibodies can restore sinus rhythm and rapidly correct bradycardia and hyperkalemia. However, the lower affinity of digoxin-specific Fab for nondigoxin cardiac glycosides in oleander results in a larger dose requirement than for usual digoxin toxicity. 13
In a patient who ingested oleander, the serum digoxin levels were high (4.4 ng/mL) and were associated with bradyarrhythmias and tachyarrhythmias, which decreased as the serum concentration of the toxin decreased. 14 Another patient who ingested 7 oleander leaves in a suicide attempt had digoxin serum levels of 5.69 nmol/L, using a digoxin radioimmunoassay. This assay confirmed the toxicity, but did not predict the severity of the toxicity. 15
 
References

1. Lampe KE. AMA Handbook of Poisonous and Injurious Plants . Chicago, IL: Chicago Review Press; 1985.

2. Radford DJ, Gillies AD, Hinds JA, Duffy P. Naturally occurring cardiac glycosides. Med J Aust . 1986;144:540-544.  PubMed

3. Duke JA. Handbook of Medicinal Herbs . Boca Raton, FL: CRC Press; 1985.

4. Leporatti ML, Posocco E, Pavesi A. Some new therapeutic uses of several medicinal plants in the province of Terni (Umbria, Central Italy). J Ethnopharmacol . 1985;14:65-68.  PubMed

5. Eddouks M, Maghrani M, Lemhadri A, Ouahidi M-L, Jouad H. Ethnopharmacological survey of medicinal plants used for the treatment of diabetes mellitus, hypertension, and cardiac diseases in the southeast region of Morocco (Tafilalet). J Ethnopharmacol . 2002;82:97-103.  PubMed

6. Manna SK, Sah NK, Newman RA, Cisneros A, Aggarwal BB. Oleandrin suppresses activation of nuclear transcription factor-ΚB, activator protein-1, and c-Jun NH 2 -terminal kinase. Cancer Res . 2000;60:3838-3847.  PubMed

7. Apted J. Oleander dermatitis. Contact Dermatitis . 1983;9:321.  PubMed

8. Arai M, Stauber E, Shropshire CM. Evaluation of selected plants for their toxic effects in canaries. J Am Vet Med Assoc . 1992;200:1329-1331.  PubMed

9. Osol A, Farrar GE Jr, eds. The Dispensatory of the United States of America . 25th ed. Philadelphia, PA: J.B. Lippincott; 1955.

10. Le Couteur DG, Fisher AA. Chronic and criminal administration of Nerium oleander . J Toxicol Clin Toxicol . 2002;40:523-524.  PubMed

11. Eddleston M, Ariaratnam CA, Sjöström L, et al. Acute yellow oleander ( Thevetia peruviana ) poisoning: cardiac arrhythmias, electrolyte disturbances, and serum cardiac glycoside concentrations on presentation to hospital. Heart . 2000;83:301-306.  PubMed

12. Fonseka MMD, Seneviratne SL, de Silva CE, Gunatilake SB, de Silva HJ. Yellow oleander poisoning in Sri Lanka: outcome in a secondary care hospital. Hum Exp Toxicol . 2002;21:293-295.  PubMed

13. Eddleston M, Rajapakse S, Rajakanthan, et al. Anti-digoxin Fab fragments in cardiotoxicity induced by ingestion of yellow oleander: a randomised controlled trial. Lancet . 2000;355:967-972.  PubMed

14. Mesa MD, Anguita M, Lopez-Granados A, et al. Digitalis poisoning from medicinal herbs. Two different mechanisms of production in Spanish. Rev Esp Cardiol . 1991;44:347-350.  PubMed

15. Romano GA, Monbelli G. Poisoning with oleander leaves in German. Schweiz Med Wochenschr . 1990;120:596-597.  PubMed