Prednisone may cause insomnia, mood changes, personality changes, euphoria, psychotic behavior, or severe depression. It may even worsen any existing emotional instability in some individuals. At a high dosage, Prednisone may cause high blood pressure and fluid retention. If this occurs, you may need a low-salt diet and a potassium supplement as a counter. With prolonged Prednisone treatment, eye problems may develop (e.g., a viral or fungal eye infection, cataracts, or glaucoma). Additionally, if Prednisone is taken over the long term, the buildup of adrenal hormones in the patient's body may cause a condition called Cushing's syndrome. This condition is marked by weight gain, a "moon-faced" appearance, fragile-thin skin, muscle weakness, brittle bones, and purplish stripe marks on the skin. Women are particularly vulnerable to this problem, however alternate-day therapy may help prevent its development.