Photo Credit pollen image by asb from Fotolia.com. Allergies are a common cause of hives since an allergic reaction can trigger the immune system response that results in trapped fluid beneath the skin. An allergic reaction can occur due to something you ingested or were exposed to through the air.hoto Credit pollen image by asb from Fotolia.com. Allergies are a common cause of hives since an allergic reaction can trigger the immune system response that results in trapped fluid beneath the skin. An allergic reaction can occur due to something you ingested or were exposed to through the air.
There are likely to be other possible causes, so ask your doctor about your symptoms. 1  Various causes of drowsiness or sleepiness include: 2  Sleep debt. 3  Not getting enough sleep. 4  Shift work. 5  Jet lag. 6  Boredom. 7  Fatigue-see various causes of fatigue. 8  Sleepiness-see various causes of sleepiness.
Even if someone with sleep apnea spends eight or nine hours in bed, the quality of sleep is so poor that it can lead to abnormal sleepiness during the day. Another sleep disorder, insomnia, is another one of the most common excessive sleeping causes. This disorder makes it difficult to fall asleep or to stay asleep.