From the down your drink site:
The effects of alcohol withdrawal
Alcohol withdrawal symptoms can occur if you stop or reduce your drinking quickly. If you are dependent on alcohol, stopping quickly can be fatal. One way to know if you are dependent is if you have to have a drink to stop yourself shaking or craving alcohol. If you are dependent you must see your doctor before trying to stop. However, most people can stop or reduce their drinking without medical supervision.
IN AN EMERGENCY CALL AN AMBULANCE AND GO TO HOSPITAL
If you have withdrawal symptoms (or are worried about them) your doctor may be able to help you overcome them. Also, if you have health problems it is important to talk to your doctor as they may also be affected by your drinking.
Alcohol withdrawal symptoms may be mild, moderate or severe.
Severe symptoms include a state of confusion and hallucinations, agitation, fever, fits and "Black outs."
Moderate symptoms include headaches, sweating, nausea, vomiting, loss of appetite, difficulty sleeping, paleness, rapid heart rate (palpitations), enlarged or dilated pupils, clammy skin, tremor of the hands and involuntary, abnormal movements of the eyelids.
Mild symptoms include feeling jumpy, shaky, anxious or nervous, irritable or easily excited, emotional, depressed, tired, difficulty with thinking clearly, concentration and memory and bad dreams.
About 95% of heavy drinkers will experience some symptoms if they withdraw from alcohol. If they are mild they will usually disappear after a few days and do not require treatment. If you have any of the severe symptoms it is important that you see your doctor immediately.
Further information can be obtained by phoning NHS Direct at any time:
NHS Helpline 0800 22 44 88
If you live in Scotland you can also phone NHS24 08454 24 24 24.