1 Poison ivy, poison oak, and poison sumac are plants than can cause an itchy rash upon contact. 2  A substance called urushiol, found in these plants, causes the rash. 3  The rash is not contagious.  The rash usually disappears in one to three weeks.
Common factors that can cause clogged ears are wax buildup, air flow blockage to the Eustachian tubes, pressure differences in the middle ear, and cold and sinus problems. Clogged ears can affect people of all ages, but is most common among children, especially when they have colds.
1 This is one of the most common causes of this condition. 2  The best way to unclog ears in this case is to try to yawn continuously. 3  Bony Growth in Ears: A common condition in swimmers, a bony growth in the outer ear may result in plugged ears to start with, followed by gradual hearing loss.