More often than not, nighttime itchiness is a nothing more than a symptom of temperature changes in the body throughout the day. We’re biologically primed to get warmer in the early evening and colder in the early morning. “Circadian regulation of sleep dictates that core temperature is maximal in the early evening and minimal in the early morning,” researchers from Temple University’s school of dermatology wrote in the International Journal of Molecular Sciences. “The consequential increase in skin temperature may be associated with increased itch intensity.” Approximately 25% of people suffer from chronic itching, and 90% of this population say the itchiness becomes most intense at night. If temperature is in fact the culprit, that would make some sense. Warmer temperatures cause moisture to evaporate from the skin, drying it out. And being warm also causes blood vessels to dilate, which makes the impulse to scratch that much worse. On top of that, corticosteroids, or anti-inflammatory hormones produced by the adrenal glands, are lower than during the day, “which leads to a decreased anti-inflammatory response and may facilitate exacerbation of nocturnal pruritus,” the study authors wrote. But there’s more than temperature at play. People tend to have drier skin with age due to fewer oil glands, and people who experience chronic itching tend to have higher rates of depression. And studies have shown that chronic pain is most intense at night, at least in part because that is when we’re least busy and most likely to notice it. It’s not inconceivable that the same would go for chronic itchiness. And then, of course, there is the occasional outside reason for scratching yourself silly in bed — mites are more active at night, and bed bugs are attracted to the heat and carbon dioxide people give off in the nighttime. In rare cases, nighttime itching can be a symptom of kidney disease, lymphoma, or a liver disorder. There are all sorts of things that can make you itch. But itchiness is usually harmless. Using moisturizer before bed might help, and antihistamines like Benadryl can provide some relief as well. So try to get some sleep. Lack of sleep is linked to a host of mental and physical health problems — and is far more likely to cause you trouble than itchiness alone.
