Passing more urine than normal (polyuria) or passing urine more often than normal (pollakiuria) may be due to:
- drinking more fluid (particularly coffee, tea, cola or alcohol which stimulate urine production),
- cold weather,
- pregnancy (when pressure is put on the bladder by the growing baby),
- fright or fear.
There are many different kidney, bladder and other organ diseases that may also be responsible.
If the bladder becomes infected by bacteria (cystitis) the patient will have a fever, feel pain low down in the front of the belly, will pass urine more frequently, and pain will be felt when passing urine. In severe cases the urine will be cloudy and sometimes blood will be seen in the urine.
Diabetes mellitus results in a higher than normal amount of sugar (glucose) circulating in the blood. The symptoms of untreated diabetes are unusual tiredness, increased thirst and hunger, belly pains, excess passing of urine, weight loss despite a large food intake, itchy rashes, recurrent vaginal thrush infections, pins and needles, dizziness, light headedness and blurred vision.
A prolapse (bulging) of the bladder into the front wall of the vagina in a woman will make passing urine difficult and uncomfortable and increases the risk of infection. The bladder cannot be completely emptied, so the woman will find that she has to pass small amounts of urine very frequently. Damage to the vagina during childbirth is the most common cause of a prolapse.
Other causes of polyuria include:
- prostatitis (bacterial infection of the prostate gland),
- kidney failure (from persistent infection or inflammation of the kidney, a poor blood supply to the kidneys, severe high blood pressure, or a number of rarer diseases),
- systemic lupus erythematosus (autoimmune condition),
- a number of psychiatric conditions, particularly those associated with anxiety and depression, may increase bladder irritability.
Diuretics are medications designed to increase urine production in conditions such as high blood pressure, heart failure and kidney failure. Other medications may have increased urination as a side effect.
Rare causes of frequently passing urine include:
- diabetes insipidus (failure of the pituitary gland in the centre of the head),
- Hand-Schueller-Christian syndrome,
- Cushing syndrome (over production of steroids in the body, or taking large doses of cortisone),
- Addison disease (adrenal gland failure),
- hyperparathyroidism (over activity of the parathyroid glands in the neck),
- Bartter syndrome.