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Medicines and drugs. Stimulants. stimulants. What are stimulants? Examples? What medical uses do they have?. stimulants. nicotine, caffeine, amphetamines the intention of these drugs is to have similar effects to adrenaline (or epinephrine) which is a natural stimulant.
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Medicines and drugs Stimulants
stimulants • What are stimulants? • Examples? • What medical uses do they have?
stimulants • nicotine, caffeine, amphetamines • the intention of these drugs is to have similar effects to adrenaline (or epinephrine) which is a natural stimulant. • amphetamines (synthetic) can do this because they have similar structures to adrenaline.
stimulants • affect central nervous system; act on the level of neurotransmitters which are chemicals that acts as messengers and stimulate pathways which … • …increases activity of the brain • largely opposite to depressants which decrease activity in the nervous system
amphetamines • group of drugs which mimic the effect of adrenaline • classified as symphatomimetic drug as it stimulates the symphatetic nervous system • adrenaline or epinephrine = hormone released in times of stress e.g. pain, cold, fear, … • response to increased adrenaline in the body: • increased heart beat/blood pressure • Increased blood flow to brain and muscles • Increased air flow to lungs • Increased mental alertness
compare • Common: both amphetamines and epinephrine have a phenyl-ethyl-amine chain which consists of a benzene ring linked to an amine group by a carbon chain (ethyl). • Different: functional groups • amphetamines: • primary amine • epinephrine: • 3 hydroxyl groups • secondary amine
nicotine • A nicotine molecule contains the following functional groups: a tertiary amine, benzene ring structures with nitrogen atoms in them (=heterocyclic rings). • Nicotine increases levels of adrenaline in the brain
caffeine • Caffeine is a psychoactive stimulant (=acts on CNS). When consumed in large amounts it can cause anxiety, irritability and sleeplessness. It is a weak diuretic i.e. causes the body to lose more water than it takes in. • Its structure is similar to nicotine.
structure of caffeine • benzene rings containing both carbon and nitrogen atoms (heterocyclic rings) • tertiary amine group • two amide groups (- N – C = O)