D5 Stimulants

• Physiological effects• Amphetamine and adrenaline (epinephrine)• Short- and longterm effects of nicotine• Effects of caffeine

Physiological effects

• Stimulants are chemical substances that enhance the activity of the brain and the central nervous system

• They cause increased alertness and wakefulness. In many cases they also act to decrease appetite.

Sympathomimetic drugs• Chemical substances that mimic the effects of

the hormone adrenalin (epinephrine)• Generally they cause constriction of the

arteries and increase metabolism• Structurally similar to phenylethylamine

adrenaline amphetamine phenylethylamine

Amphetamine derivativesSpeed

Ecstacy

Amphetamine• Synthesised from ephedrine• Initially used to treat narcolepsy• Issued to airmen in World War II- Wakey-Wakey-

pills• Anti-depressants and slimming pills• Regular use can lead to tolerance and dependance• Short-term effects- increase in heart rate and rate

of breathing, dilatation of pupils• Long-term effects- weight loss, constipation and

emotional instability

Ephedra plant

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Nicotine• Nicotine is an

alkaloid found in the nightshade family of plants (Solanaceae)

• It constitutes approximately 0.6–3.0% of dry weight of tobacco

AlkaloidsNitrogen-containing compounds found in plants with heterocyclic rings and a tertiary amine group

Cocain Nicotine

Caffeine

Morphine

Ergometrin, cf LSD

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Nicotine - Short Term• Sympathomimetic• Increases

concentration and relieves tension

• Increases heart rate and blood pressure

• Reduction in urine output

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Nicotine – Long Term

• Highly addictive• Increased risk of heart disease and coronary

thrombosis• Increased stomach acid and risk of peptic

ulcers• Chronic lung disease• Increased risk of cancer (lung, throat, mouth)

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• Cessation of smoking difficult

• Cravings • Nausea, weight

gain, insomnia, irritability, and depression

Nicotine - Addiction and Withdrawal

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Caffeine Characteristics

• Widely used stimulant found in coffee, chocolate and tea

• Added to some pain killers to speed up their effects, e.g. aspirin

• Diuretic (frequent urination)• Increases alertness, concentration and

restlessness• Can cause anxiety, irritability and sleeplessness

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• Found in chocolate• Effects similar to

caffeine• Although

theobromine does not cause harmful effects with humans, it is highly toxic to some domestic animals, including dogs and horses

Theobromine

Theobromine

Caffeine