Post on 11-May-2015
Stimulants
Chynna & April
Stimulants
Drugs that increase a person’s mental alertness and awareness by stimulating the brain and central nervous system
They are drugs that alter the levels of neurotransmitters
They act as opposites to depressants. Examples: amphetamines, epinephrine
(adrenaline), nicotine, caffeine
D.5.1 List the physiological effects of stimulants
Physiological effects:
increase in heart rate blood pressure constriction of arteries relaxation of air passages therefore an
increase breathing rate dilation of pupils sweating reduced appetite Increase concentration
D.5.1 List the physiological effects of stimulants
Other long term side effects:
emotional instability or depression restlessness sleeplessness delusions and hallucinations
D.5.2 Compare amphetamines and epinephrine (adrenaline)
Epinephrine (adrenaline): a hormone secreted by the adrenal medulla upon stimulation by the central nervous system A response to stress Results in Anger or fear Causes: increased heart rate, blood
pressure, cardiac output, carbohydrate metabolism
D.5.2 Compare amphetamines and epinephrine (adrenaline)
Amphetamines : chemically related to adrenaline Sympathomimetic drug Initially used to treat narcolepsy and issued to
airmen in WWII to combat fatigue. 50s and 60s used as anti-depressants and slimming
pills. Regular use can lead to both tolerance and
dependence Short-term effects: increase heart race and
breathing, dilation of pupils, decrease in appetite fatigue possible depression (as it wears off)
Long term effects: weight loss, constipation, emotional instability
D.5.2 Compare amphetamines and epinephrine (adrenaline)
Physiological Similarities
Increase physical energy by: 1) Increasing heart rate and blood pressure. 2) Increasing blood flow to the brain and muscles. 3) Increasing air flow to the lungs
Increase mental awareness; trigger the "fight or flight" syndrome
Dilation of the pupils Reduce appetite induce a sense of euphoria Both can lead to the rapid development of both tolerance and
dependence (addiction), Both can have serious long-term effects if abuse/over used -
depression and reduced resistance to infection. Abuse of amphetamines through overuse is a serious problem.
D.5.2 Compare amphetamines and epinephrine (adrenaline)
Physiological Differences
epinephrine (adrenaline) is regulated/produced naturally by the brain
amphetamines are synthetic drugs Amphetamines are
sympathomimetic
D.5.2 Compare amphetamines and epinephrine (adrenaline)
Sympathomimetic drugs
Mimics the effect of stimulation on the sympathetic nervous system, which deals with subconscious nerve responses
Mimic the effects of naturally produced epinephrine (adrenaline)
speeds up heart rate increases sweat production increases breathing rate examples: nicotine, amphetamine,
methamphetamine, speed, ecstasy
Comparison of the Structures (similarities and differences)
Both based on the phenylethylamine structure Both have a benzene (aromatic) ring with a hydrocarbon
chain containing an amine. Primary amine (1 C atom attached to N atom) in
amphetamine and secondary amine (2 C atoms attached to N atom), NH in epinephrine.
Epinephrine has three hydroxy (-OH) groups while amphetamine has none.
Ethyl Amine Structure
D.5.3 Discuss the short & long term effects of nicotine consumption
Nicotine - obtained from tobacco plants, tomatoes, potatoes, eggplants, green peppers
Usually it is taken in by inhalation of smoke from cigarettes, cigars, and pipe tobacco, and chewing.
A fat soluble molecule and is easily able to go through blood-brain barrier and thus affects brain activity.
Increases the release of adrenaline effects change with time, bringing about
dependence and increased toleration.
Nicotine
Largely responsible for 1/3 of the world’s population being addicted to smoking
Withdrawal symptoms: craving for tobacco, nausea, weight gain, insomnia, irritability, and depression
Sympathomimetic drug
D.5.3 Discuss the short & long term effects of nicotine consumption
Short term physiological effects of nicotine:
increased heart rate / blood pressure reduced urine output as stimulating effect Increased levels of concentration/
alertness Reduced anxiety and tension Constricts blood vessels stress to heart Smoking for the first time: nausea,
vomiting, diarrhea
D.5.3 Discuss the short & long term effects of nicotine consumption
Long term physiological effects:
Increased risk of cancer Increased risk of heart disease/coronary thrombosis/peptic
ulcers Increased risk of stroke Withdrawal symptoms/Weight gain on quitting Physical and psychological dependences and tolerance Toxic chemicals from smoking can increase risk of mouth,
throat, and lung cancer CO from smoking reduces ability of the blood to carry CO2 Increased risk of bronchitis and emphysema Cigarettes are costly nicotine addiction increases financial
strains on families Can cause lung disease and adverse effects on pregnancy
D.5.4 Describe effects of caffeine & compare structure with that of nicotine
Caffeine: most widely used stimulant Present in coffee, tea, cola drinks, some pain killers, other
medicines Evidence that consuming 400 mg of caffeine a day or
more can cause dependence and physical side effects Caffeine is a respiratory stimulant In general, an intake of more than four cups of coffee per
day is excessive. Pregnant women are advised to limit their caffeine intake.
Included in common painkillers to speed up effects (ex. nicotine, morphine, codeine, cocaine)
Is an Alkaloid – nitrogen-containing compounds of plant origin containing heterocyclic rings and tertiary amine groups
Stimulates the nervous system by increasing the metabolic rate of nerve cells.
D.5.4 Describe effects of caffeine & compare structure with that of nicotine
Caffeine Content of different products
Cup of ground coffee 80-120 mg Cup of instant coffee 65 mg Cup of tea 40 mg Cup of cola 40 mg Bar (100g) of plain chocolate 80 mg
D.5.4 Describe effects of caffeine & compare structure with that of nicotine
D.5.4 Describe effects of caffeine & compare structure with that of nicotine
D.5.4 Describe effects of caffeine & compare structure with that of nicotine
Comparison of the structures of nicotine and caffeine
Similarities
Both contain a tertiary amine group. Both contain and five member rings made of carbon and nitrogen
atoms. Both contain a six member ring made of carbon and nitrogen
Differences
Caffeine contains two amide groups, nicotine does not. Both contain an alkene (C=C) group. Caffeine has one and nicotine
has two In caffeine the six and five member rings are fused while in nicotine
they separated. Caffeine contains two carbonyl (C=O) groups and two amide (-N-
C=O) groups