FEUILLE DE COCA
The coca tree is a small tree native to the tropical regions of South America that can grow 5 to 6 m in the wild, but is usually pruned to stay shorter and allow the leaves to be harvested easily.
The branches, straight and alternate, are often reddish (hence its name Erythroxylum), the green leaves are between 2 and 5 cm long, they have a central part delimited by two curved lines especially visible on the lower face.
While drying they remain flat, their smell is pleasant, a little aromatic (sometimes smell of tea when they begin to dry).
The flowers are whitish, pentamerous, and the fruit, a red drupe is oblong, red, about 1 cm long.
Erythroxyum coca and Erythroxylum novogranatense have been cultivated for a very long time throughout the Andean region, there are several varieties.
They are mainly found in the equatorial and humid tropical zone (between 300 and 2000 m) of South America (Venezuela, Colombia, Ecuador, Peru, Brazil), on the first slopes of the Andes ( the yunga), and the Amazonian plain; the coca tree can adapt to other regions and is thus present in other countries with tropical or sub-tropical hot climate with a marked wet season (Mexico, West Indies, Africa (Cameroon), Indonesia (Java), Sri-Lanka (Ceylon), Australia)
CHEMICAL COMPOSITION AND MEDICINAL PROPERTIES
The leaves contain:
• a dozen alkaloids (ecgonine derivatives) whose content varies between 0.5 and 1.5%.
The major constituent (30 to 50%) is cocaine (methylbenzoilecgonine), a low molecular weight substance (303.4), soluble in water, alcohol, ether and certain oils and derivatives of oil, it is an alkaloid ester, volatile in the basic state.
The rate of cocaine varies during the day, a study shows that it is stronger in the morning and at the end of the afternoon (respectively in the study: 7 and 9 mg per g of dry weight).
Once harvested, the leaves are quickly dried because the cocaine disappears very quickly if there is fermentation.
• a little essential oil
• carbohydrates (starch, dextrin, sugars and cellulose), and some protein.
They have some nutritional value (about 3 calories per g)
Depending on the amount of cocaine ingested, the effects felt are:
• local anesthesia of the mouth and gums,
• mild euphoria and temporary disappearance of the feeling of fatigue and hunger.,
• increased heart rate and blood pressure, mydriasis (the pupil widens) ,
Cocaine is indeed a local anesthetic and a sympathomimetic:
There is blockage of the reuptake of norepinephrine and therefore, at first, adrenergic stimulation (intellectual stimulation, feeling of euphoria, increase in body heat, local phenomena of vasoconstriction ), followed by a depressing effect on the nervous system (following the inhibition of reuptake), with a feeling of psychic and physical fatigue.
Toxicologists believe that cocaine does not induce physical dependence but may induce a strong psychic dependence.
The leaves of E. coca are used as a stimulant in the western part of South America.
For centuries Andean Amerindians chew coca leafs (an average of 60 g per day for a regular), often mixed with vegetable ashes (ashes of quinoa or certain cactus roots, sometimes mixed with apple starch)) or lime (lime or ash potash promotes the chemical release of cocaine).
In fact, these leaves are only chewed to crush them and they are then preserved in the form of a quid on the side of the mouth, the saliva extract the juice that contains cocaine; the alkaloid also penetrates through the oral mucosa directly into the bloodstream; it is the most common use.
The coca leaf is also smoked but this is much rarer.
In South America, coca tea (maté de coca) is now commonly consumed; it is sold ready-made in the form of tea bags (like normal tea) containing about 1g of leaf.
One study showed that the alkaloid content of these tea bags was variable, but was around 5 mg of cocaine, and between 0.1 and 3 mg for the other significant alkaloids (benzoyl ecgonine, methyl ecgonine, cinnamoylcocaine.
The consumption of one cup of coca tea would correspond, according to this study, to the ingestion of about 4 mg of cocaine, the metabolites of cocaine are eliminated in the urine and so an urine test could be positive for cocaine after drinking a coca tea .
• Coca leaf or its galenic derivatives are no longer used in Western medicine;
for the anecdote, remember that the "coca cola" originally contained (in 1892) extracts of coca leaves and therefore cocaine, his "inventor", the American Pemberton stole the idea to Franco -Italian Mariani who marketed since 1863 a "tonic wine" with coca; the formula of "coca cola" remained unchanged for about ten years; in 1903 the coca was removed from "coca cola".
• The coca leaf is often recommended in South America to combat the effects of "altitude sickness" or "soroche", a physiological disorder that combines headaches, palpitations, vomiting, lack of appetite and sleep disorders. The "soroche" can occur for a few days above 3000 m altitude when one is not accustomed to high altitude.
• Here is the opinion of a scientist from the USA, during a congress in 1979, on the consumption of the coca leaf and its use as a medicinal plant: Journal of Ethnopharmacology, 3 (1981) 367-376 The therapeutic value of coca in contemporary medicine Dr Andrew T Weil Botanical Museum, Harvard University Cambridge, MA, USA
Local people use the coca leaf as medicines:
• to anesthetize the mouth in case of mouth ulcers, dental pain or inflammation of the gums,
• in cases of non-infectious acute colitis, such as irritable bowel syndrome,
COCA LEAF INTOXICATION
Clinical signs of intoxication by the coca leaf:
The manifestations of poisoning depend on the amount ingested, and the addiction of the patient to cocaine:
- at a minimum, euphoria, excitement with agitation, disappearance of fatigue, increased physical performance, better resistance to effort,
- if the dose is higher, some hallucinations are possible with tachycardia, mydriasis, arterial hypertension and sometimes abdominal pain
- later the nervous system is disrupted (depression): breathing becomes irregular, convulsions or coma and serious cardiovascular disorders can occur which can lead to death.
In case of acute intoxication:
Remove the leaves from the mouth, clean and, if possible, promote vomiting (with ipecac syrup for example), unless the person is unconscious or convulsing.
Chronic intoxication leads to a decrease in the sensitivity of the oral mucosa, the local irritation by the leaf quid and the induced vasoconstrictor phenomena can cause the appearance of oral ulcers; weight loss, character disorders and possible deterioration of mental faculties.
The cultivation of the coca tree and the transport of the coca leaf are forbidden by international conventions except special derogations.
The drug "cocaine" (cocaine hydrochloride) and other substances derived from the coca leaf (coca paste, cocaine "base", "crack") are strictly prohibited in most countries.
THE INCA DRUG
The coca tree is native to South America where it has been cultivated for a long time, its leaves are chewed, and have helped for hundreds of years the Andean Amerindians to bear the harsh living conditions of the altiplano and the forced labor of the Spanish colonizers.
It is a plant still widely used in South America.
Cocaine, extracted from coca leaves, is one of the first medical alkaloids used in medicine. It is now a substance whose possession and trade is strictly controlled all over the world.
Copyright 2018 : Dr Jean-Michel Hurtel