When you drink too much alcohol, then you can get hangover. Hangover is a group of unpleasant signs and symptoms which are happening after someone has drank a lot of alcohol. If you have frequent hangovers, then they can be associated with poor performance and conflict at work . It is known fact that as more alcohol you drink, the more likely you are to have a hangover the next day. No one can tell you how much alcohol you should drink if you want to avoid hangover. In the most cases unpleasant hangovers go on their own but they can last up to 24 hours. If you have chosen to drink alcohol, then you must be careful how much you are drinking if you want to avoid hangovers. It is known fact that alcoholic beverages have a component known as congeners which is giving to many types of alcoholic beverages their flavor and they can contribute to hangovers. This component is found in larger amounts in dark liquors such as bourbon and brandy, than in clear liquors, such as gin and vodka. This component is also increasing the chances of having hangover or increase the severity of a hangover . When you are drinking too much alcohol of any color, it can make you feel bad in the next morning. Avoid drinking alcohol if you want to avoid hangovers because no one will tell you how much amount of alcohol you can drink.
The symptoms of hangover usually begin when the blood alcohol content drops significantly and it is at or near 0. In the most cases, the symptoms of hangovers are in full effect in the morning after a night of heavy drinking. It depends on what and how much you drank to notice symptoms, such as
- Rapid heartbeat
- Mood disturbances, such as depression, anxiety and irritability
- Decreased ability to concentrate
- Dizziness or a sense of the room spinning
- Increased sensitivity to light and sound
- Poor or decreased sleep
- Nausea, vomiting or stomach pain
- Headaches and muscle aches
- Excessive thirst and dry mouth
- Fatigue and weakness
It is known that hangovers are caused by drinking too much alcohol. There are some people who can drink a single drink and have a hangover while other people can drink heavily and they can escape the hangover entirely. There are some factors which could lead to hangovers such as
- Alcohol can make you sleepy: When you drink alcohol, then it can make you sleepy but it prevents deeper stages of sleep. This often is causing awakening in the middle of the night. This can leave you tired and groggy. 
- Alcohol causes your blood vessels to expand: This can lead to headaches. 
- Alcohol can cause your blood sugar to fall: If the blood sugar dips too low, then the affected person can experience mood disturbances, shakiness, weakness, fatigue and even seizures. 
- Alcohol irritates the lining of your stomach: It can increase the production of stomach acid and it can delay the stomach emptying. Any of the mentioned factors can cause vomiting, nausea or abdominal pain.
- Alcohol triggers an inflammatory response from your immune system: We know that our immune system can trigger some agents which commonly produce physical symptoms such as loss of interest in usual activities, decreased appetite, memory problems and inability to concentrate. 
- Alcohol causes your body to produce more urine: When you are urinating more than usual, then it can lead to dehydration which is often indicated by lightheadedness, dizziness and thirst.
Risk factors: Here are some factors which are making a hangover more likely or severe:
- Drinking darker colored alcoholic beverages
- Having a family history of alcoholism
- Not sleeping well or long enough after drinking 
- Using other drugs, such as nicotine, along with alcohol
- Drinking on an empty stomach
Complications: When you have a hangover, then you are likely to experience problems with:
- Dexterity 
This temporary dulling of your abilities can increase your risk for many problems at school or work  such as
- Workplace injuries
- Falling asleep at school or on the job
- Conflict with others
- Trouble completing tasks
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