Think a little. It has been a very long and tiring day and you can hardly wait to go to bed. You are ready to sleep but you feel the need to scratch your arms a little, then your legs and so on until now you can not sleep out of annoyance. What is happening?

According to Joshua Zeichner, an associate professor in the dermatology department and director of cosmetic research at a New York hospital, it turns out that the feeling of itching when you lie in bed at night is more common than you think. However, scientists do not know exactly why. However, they do have some suggestions on how to ease the irritating sensation and sleep soundly.

One theory, though not officially proven, is that the feeling of itching when you go to bed to sleep is related to your body’s circadian rhythms, says Brian Kim, physician. Some of the body’s internal chemicals can be numerous at night, so the itching sensation may appear more at night.

Another theory why you may feel itchy when you lie down at night - also not scientifically confirmed - is because you are more focused on how you feel physically, says dr. Zeichner. During the day, distraction from work and other tasks may make it easier to suppress the itching sensation.

Itching at night can only have to do with how your skin works, says dr. Zeichner. Skin hydration levels tend to decrease in the afternoon, and the decline continues into the evening. "This means that the skin is likely to be drier overnight, contributing to the dysfunction of the skin barrier, drying, inflammation and itching," he says.

To stop annoying itching, your doctor recommends applying moisturizing lotions or creams to your skin before bed. Also, if you have allergies or sensitive skin, you can use hypoallergenic or fragrance-free detergents for washing clothes. 

If all else fails, get rid of acne scars - go to a dermatologist!