General CNS Stimulants Caffeine (and other methylxanthines, theobromine and theophylline) – affect multiple pathways, including stimulation of norepinephrine.

General CNS Stimulants

• Caffeine (and other methylxanthines, theobromine and theophylline) – affect multiple pathways, including stimulation of norepinephrine receptors and modulation of dopamine release. May also affect serotonin receptors

• most commonly consumed psychoactive compound

• many plant sources ( methylxanthines act as a natural deterrent to herbivorous insects)

CaffeineCaffeine

Mechanism of action

Caffeine is the most widely used psychoactive substance in the world, produces mild CNS stimulation through the inhibition of the enzyme phosphodiesterase. (Adenosine receptor antagonist). This prolongs the effect of neurotransmitters (especially noradrenaline).

Effects of Caffeine

Caffeine causes an increase in cellular activity in the CNS, and behavioral and emotional responses that are similar to, but milder than, the amphetamines and cocaine. After consuming caffeine, people report thinking more clearly, having more energy, and having faster reaction times increased alertness, energy, and ability to concentrate--occur after consumption of low to moderate doses (50-300 mg). Moderate caffeine consumption very rarely leads to health risks.

Long-term Effects

Regular use of more than 600 mg a day (about eight cups of coffee) can cause

Chronic insomnia Persistent anxiety Depression Stomach upset

Toxicity of Caffeine (Caffeinism)• This disorder is a chronic toxicity caused by high levels of caffeine Consumption (caffeine

overdose) 750 mg (7 cups of coffee). It is characterized by:

• Disruption of sleep patterns• Nausea• Depression• Diarrhea • Stomach pain• Headache • Feelings of anxiety• Trembling • Ringing in the ears• Dry mouth • Irregular heart beats• Palpitations & Rapid changes in mood

General CNS Stimulants

• plant sources of methylxanthines include:• Coffea robusta (coffee)• Camellia sinensis (tea)• Theobroma cacao (chocolate)• Cola acuminata (cola nut)• Ilex paraguariensis (mate)• Paullinia cupana (guarana)

Coffea arabica, C. robusta

Camellia sinensis

Theobroma cacao

Cola accuminata

Ilex paraguariensis

Paullinia cupana

CNS Stimulants: Catha edulis

• khat, qat• cultivated in Ethiopia,

Somalia & Yemen• fresh leaves chewed

socially as a stimulant• active compounds are

cathine (d-norisoephedrine) and cathione

CNS Stimulants: Catha edulis

• appears to slow the re-uptake of norepinephrine, leading to stimulation of CNS / wakefulness

• cathione also has a high affinity for serotonin receptors, which is likely responsible for euphoria produced by qat use

Peyote is a globular cactus called: Lophophora williamsii, Cataceae.

This is the “plant that makes the eyes amazed”, in other words causes visual hallucinations; due to the CNS activity of a phenethylamine alkaloid,mescaline.

Peyote, Lophophora williamsii, Cactaceae

Mescaline..

History of use & abuse

It was ingested by indigenous people in Mexico and the United States to produce visions.

The use of peyote is said to produce a mental state that allows celebrants (in peyote-eating tribal ritual) to feel closer to their ancestors and their Creator.

Physiological & psychological effectsThe effective human dosage is 200–400 milligrams (3.75 mg/kg), with the effects lasting for up to twelve hours .A distortion of the perception of shapes , intensification of colors .auditory hallucinations .slowing in the perception of time .mydriasis .sensation of change in temperature .possible agitation & anxiety .

Iboga

Tabernanthe Iboga F.Abocyanaceaea shrub endogenous to equatorial African particularly in

the rain forest of Congo and GabonIts big roots whose barks contain 5-6 % indol alkaloids:

ibogain (the principal constituent), tabernanthin, ibogaline, ibogamine.

Gabon: roots used for its antisporific properties and its ability to increase resistance to fatigue.

Ibogaine• Ibogaine is a CNS stimulant either amphetamine-like

or hallucinogenic depending on the dose.• High doses in human can cause paralysis and even

respiratory arrest for these reasons it’s prohibited in several countries.

• IT’S CHOLINESTERASE INHIBITOR causing hypotension and stimulation of digestion and appetite.

• It’s long acting hallucinogens resembles LSD in effect but it’s stronger stimulant.

Ephedra sinica

Ephedra sinica , a species of ephedra (Ma-huang). Contains the alkaloids :ephedrine,pseudoephedrine .

Pharmacology

•Central stimulation: Increases arousal and wakefulness .•Other uses:--Brochdilater.-Nasal decongestant.-Hypotention.-In combination with caffiene,ephedrine appear to elicit Wt loss.

Toxicity

• Toxicity of Ephedra has been reporeted word wide and many people died from using it . Epherda or ephedrine increased blood pressure and blood clotting.

Magic Mint

• The hallucinogenic plant Salvia divinorum has been used for centuries in shamanistic ceremonies led by spiritual healers in Mexico. But now the drug has gotten so popular among recreational users.

Mexican salvia

Method of uses

• According to recent surveys, users say burning and inhaling the smoke of dried Salvia leaves produces powerful hallucinogenic effects, and helps reduce anxiety, improve mood and increase insight.

• The plant can be chewed.

Salvinorin A

Psychedelic experiences• Aside from individual reported experiences there has been a

limited amount of published work, summarizing the effects. may include:

• Uncontrollable laughter• Past memories, such as revisiting places from childhood

memory• Sensations of motion, or being pulled or twisted by forces• Visions of membranes, films and various two-dimensional

surfaces• Merging with or becoming objects• Overlapping realities, such as the perception of being in

several locations at once