EFFECTS :
Parasympatomimetic: euphoria, stimulation of cental nervous system, vertigo.
Autonomic changes: stimulation of salivary glands and immunesystem, retching, miosis, tremor, bradycardia.

DURATION :
The effects start within a quarter of an hour after ingestion and last for a few hours.

Dosage and preparation
Betel nuts may be chewed solely, but also in combination with lime and betel leaves (Piper betel). The nuts may also be smoked. When the nuts dry up, they harden. By that chewing may become difficult. The betel leaves, which contain phenols, probably produce synergistic effects in combination with betel nuts.1, 4 Lime (Ca(OH)2 ) quickens the absorption and elimination of the main psycho-active ingredient, arecoline. Natural sources of lime are coral, limestone and sea-shells.
A dose consists of 1-4 grams (resp. 1/4-1/2 nut). Four grams is the maximum dose. 8-10 grams of pulverized nut may be lethal. Unripe nuts are more potent than the ripe ones

Figure: Areca nuts

Figure: Pulverized Areca seeds

Botanical aspects
A. catechu is a member of Arecaceae; subcategory Ceroxylinae-Arecineae, Tribus Areceae. The geographical background of this species is not certain (it might have originated from philipines), but at the present time it is spread out over the entire world as an ornamental.
The areca palm trees blossom when they have reached a minimum age of 10 years and continue their seed production for 45-70 years. These fanpalms can reach 25 meters in height, can produce 150-200 fruits. This species is easily interchanged with Veitchia and Roystonea palm species, but is also almost indistinguishable with closely related Areca species like A. triandra, A. vestiaria.

Figure: A. catechu

Figure: The constructed leaves

Phytochemistry
The Areca seeds contain 0.3-0.6 % alkaloids of which arecoline (methyl-1,2,5,6-tetrahydro-1-methylnicotinate) is the major constituent (0.1-0.5 %). The other structurally related alkaloids found in betel nuts are guvacoline, arecaidine, guvacine and arecolidine. 2, 5 Arecaidine and guvacine are hydrolyse products of arecoline and guvacoline.


Table 1.6: Areca alkaloids

PHARMACOLOGY :
In vivo arecoline acts as a parasympatomimetic; it is a muscarinereceptor-agonist. The agonist properties are ascribed to the resemblance to acetylcholine that arises after protonation of arecoline's nitrogen atom. 2
The more hydrophilic arecaidine and guvacine appear to be strong inhibitors of GABA-uptake into the nerve endings.6 In addition, the plasma concentrations of adrenaline and noradrenaline are increased after betel nut ingestion. 6

Synergic effects occur when betel nuts are taken simultaneously with Piper betel leaves. This action is might be ascribed to the phenolic structures present in the leaves; the phenols have been shown to stimulate the release of catecholamines in vitro. 6
Although the pharmacological actions of betel nuts are multiple, the data avalaible is only fragmentary, so further research is nessesary.

MODIFIERS :
- lime (Ca(OH)2 ) quickens the absorption and elimination.
- Muscarinereceptor-antagonists (for example, atropine-like substances) counteract the effects.

REFERENCES :
- Davidson, Steef
1982, Drugs, kruiden van hemel en hel.
- Ratsch, Christian
1998, Enzyklopadie der psychoaktiven pflanzen
- Forth, W, D. Henschler, W. Rummel, U. Forstermann and K. Starke
2001, Allgemeine und spezielle pharmakology und toxikologie
- Gottlieb, Adam
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