Caffeine

Caffeine is a mild stimulant, which makes you feel more alert and awake. In higher doses it may make you feel jittery and prevent you sleeping. It can be addictive and lead to withdrawal symptoms when stopped. Caffeine is found in coffee, tea, soft drinks and chocolate. In lesser amounts it is an active ingredient in cold and flu remedies, decongestants and painkillers

HOW MUCH CAFFEINE IS THERE IN A DRINK?
The amount of caffeine in a cup of coffee or tea varies enormously. An increase in brewing time makes a stronger cup. Some suggested figures are:

Generally: 200-500mg/day is regarded as moderate use - 600-750mg/day is regarded as high use - Over 1,000mg/day is regarded as a toxic amount

WHAT HAPPENS TO CAFFEINE IN THE BODY?
It takes 15-45 minutes for caffeine to reach its peak level in the blood. It reaches the brain and causes maximum stimulation in 30-60 minutes. Caffeine:

• Increases heart rate and pulse
  
• Increases breathing
• Increases adrenaline
• Drinking tea or coffee is a social activity and can be enjoyable
• It provides a welcome break from work and other activities
• Feel awake and alert - especially in the morning
• Feel less drowsy and tired
• Concentrate better
• Think more clearly
  

Unwanted effects occur at higher doses but vary from person to person. A moderate caffeine intake may make a person feel that they are having a stressful day. Caffeinism is the name given to the effects of too much caffeine. It can occur with 250-750mg of caffeine and can cause the following:

• Anxiety and nervousness
• Sleep problems
• Headache and tremor
• Restlessness and irritability
• Produces more stomach acid and urine - going to the toilet a lot
• Nausea and stomach complaints (heartburn, indigestion, may aggravate ulcers)
• Tense muscles
• Palpitations and irregular heart beats (arrhythmia)
• Increases blood pressure
  

The symptoms of caffeinism are similar to the symptoms of anxiety and depression. At higher doses caffeine may cause:

• Anxiety attack
• Panic attack
• Delirium
• Ringing in the ears
• Flashes of light
  

DEPENDENCE & TOLERANCE
Caffeine is addictive. Individuals come to rely on it to give them a boost. Tolerance occurs when individuals require increasing doses to give the same effect. This is a sign that they are adapting to the drug and they will probably experience withdrawal symptoms when caffeine is stopped. Withdrawal Symptoms usually occur within 18-24 hours of stopping and may last for 3-4 days. The symptoms are:

• Throbbing headache, nausea and yawning
• Drowsiness and lethargy
• Depression, irritability and nervousness

CAFFEINE & SLEEP
The effect of caffeine on sleep varies from person to person, depending on its use. Sleep disturbance can occur with as little as one cup of coffee drunk 30-60 minutes before bedtime. Heavy users of caffeine may become accustomed to a disturbed sleep pattern, while the occasional user may report more difficulties in sleeping. Caffeine causes:

• Difficulty getting to sleep and restlessness
• Reduced sleep time and quality of sleep
• Reduced dreaming time and frequent awakenings
  

If you have difficulty sleeping, reduce your caffeine intake or avoid it 5-7 hours before bedtime

CAFFEINE & ALCOHOL
Caffeine and alcohol have the opposite effects i.e. alcohol is a depressant while caffeine is a stimulant. However caffeine does not sober up a drunk person. Caffeine may help them feel more alert but will not lower the blood alcohol level. Thus co-ordination and reaction time remain impaired

IS CAFFEINE HARMFUL
Caffeine appears to be safe in moderation - up to 500mg /day. However some people may be sensitive to doses which are less than this. Caffeine use becomes troublesome if you have to use it to stay awake, help you work, make you feel better or if you suffer from any of the effects listed above. Children may drink a lot of caffeine in the form of soft drinks in preference to milk. The caffeine effect on children will be greater due to their smaller body weight

AM I HAVING TOO MUCH CAFFEINE?

• Keep a diary - each day for one week, write down all caffeine containing drink/foods you have
• Add up the amount of caffeine you have had
• If it is between 250-750mg, you may have symptoms of caffeinism and might want to consider reducing or stopping it
• If it is above 750mgs per day, you are drinking too much

HOW TO DECREASE YOUR CAFFEINE INTAKE

• Reduce slowly - stopping abruptly may produce withdrawal symptoms
• Gradually reduce over a few weeks
• Cut down by one cup every 3-4 days; replace with decaffeinated or caffeine free drinks or water
• Drink weaker coffee/tea and avoid brewed tea and strong coffee
• Avoid caffeine in other foods/drinks, e.g. chocolate
• Avoid over the counter caffeine products e.g. some headache tablets

HOW TO OVERCOME TIREDNESS WITHOUT CAFFEINE

• In the morning, try a cool shower, deep breathing or exercise
  
• At work, try to get some fresh air during breaks
  
• Try to sleep more each night
  
• Eat healthier food
  
• Increase exercise
  
• Reduce stress
  
• Increase times of rest and relaxation
  

HELP AND SUPPORT

• Your own doctor
• NHS Choices - 0845 46 47 (24 hours). Free information service on all aspects of health problems, NHS services and other local services www.nhs.uk

Source text: Leeds Mental Health Trust and NHS Leeds
Image source: bbc.co.uk
The original version of this leaflet was written by Ardsley Community Mental Health Team, East Ardsley Health Centre, Wakefield WF3 2DN

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Last revision: December 2008