If the shaking is occurring only during sleep then you have nothing to worry about. traffic could be the cause and you wake up after it had passed and caused you to shake. Make sure you have a snack before you got to sleep so your sugar levels do now go down during sleep as that could be a cause also. other causes are : Cold Exposure to sudden or extremely cold temperatures may cause shaking in your body as a your body exerts effort to become warmer. Medications If you take medications such as amphetamines, corticosteroids or stimulants, these medications may cause side effects such as shaking in your body. Alcohol You may have shaking in your body after a binge of alcohol consumption, if you are alcoholic or as a side effect of withdrawal from alcohol. Dystonia Dystonia is the medical term for abnormal contractions of your muscles that can cause shaking all over your body or in just one location, such as your hand. Neurological Disorders Progressive neurological disorders such as Huntington s disease or Parkinson s disease may cause symptoms such as shaking, especially in your hands and arms.