Symptoms of withdrawal are the opposite of the pharmacological effects of alcohol consumption. As noted above, alcohol inhibits the activity of central nervous system and therefore produces sedation. During the withdrawal the central nervous system is experiencing the opposite effect: they increase the active processes while the processes are diminished depressants. These changes lead to an overactivation of central nervous system in pain from the patient, such as withdrawal symptoms.
This overactivation, which has been observed in clinical trials in patients with moderate withdrawal symptoms, is experienced sympathetic nervous system hyperactivity and an increase, which can be toxic to nerve cells, production of hormones such as cortisol and norepinephrine . It has been seen, even in people who abuse alcohol only occasionally, the hangover of the “morning after” is actually a mild form of the withdrawal symptoms while the amount of alcohol in the blood decreases.
In some patients have a lower chemical dependency, alcohol withdrawal symptoms can be so “soft” and experience tremors, sweating, nausea, headaches, anxiety or increased heart rate and blood pressure. Although these symptoms are uncomfortable, are not necessarily dangerous. But are often accompanied by a strong desire or craving to consume more alcohol, so the decision to continue abstinence or to stop drinking is much more difficult.
Impairment or distress, as manifested by three (or more) of the following, at some point in a continuous period of 12 months:
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