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.
Before going into an explanation of why there are occasions when the ear doesn't feel right (ear fullness, clogged ears, fluid sensation) or makes unusual noises (ear crackling/popping), one must understand the anatomy of how the ear works when things are normal.If your ears hurt, click here.efore going into an explanation of why there are occasions when the ear doesn't feel right (ear fullness, clogged ears, fluid sensation) or makes unusual noises (ear crackling/popping), one must understand the anatomy of how the ear works when things are normal. If your ears hurt, click here.