The short answer:
Clear urine without drinking water is commonly due to excess fluids (non-water), caffeine, alcohol, some medications, and undiagnosed or uncontrolled diabetes.
What you need to know:
- The most common cause of clear urine without drinking water is the consumption of excess fluids such as sodas, beer, alcoholic beverages, fruit juices, etc.
- Some medications may cause clear, colorless urine, such as diuretics, some anti-diabetes medications, anti-hypertension, and antidepressant medications.
- Excess caffeine in coffee and other products may also be a cause
- Excess alcohol in highly concentrated alcoholic beverages.
- Diabetes mellitus (undiagnosed or uncontrolled) causes osmotic diuresis, which leads to clear urine.
- Other less frequent causes include diabetes insipidus, pregnancy, hypercalcemia, excess IV fluids, kidney failure, and crushing’s syndrome.
Table of Contents
1. Excess caffeine.
Caffeine is a potent diuretic; drinking coffee will increase your urine output and may cause clear urine without drinking water. The effect of caffeine is dose-dependent; The more caffeine you drink, the more polyuria and clear water-like urine you will get.
Common examples are illustrated in the table below:
2. Over-hydration from non-water sources.
You may get colorless, water-like, or clear urine by drinking too many fruit juices or fluids that are not water. Examples include:
- Too many fruit juices.
- Drinking too much alcohol or beer.
- Too many soda or carbonated drinks (Pepsi, Coca-Cola, 7Up, Sprite, Fanta, etc.).
- Too much milk.
- Eating Too many high-water fruits (such as watermelons, oranges, cantaloupes, peaches, etc.).
Many medications are intended to increase urine volume (diuretics). Also, some medications may lead to polyuria as a collateral effect.
Medications that increase urine output produce pale yellow or clear white urine according to its potency and dose.
- Diuretics such as furosemide (Lasix@), Aldactone, hydrochlorothiazide etc.
- Some antihypertensive medications include Cardura, Amlodipine (Norvasc®), and Felodipine (Plendil®).
- Some diabetes medications such as Dapagliflozin (Farxiga), canagliflozin (Invokana®), and empagliflozin (Jardiance).
- Tamsulosin (Flomax®) used for the treatment of being prostatic hypertrophy (BPH).
- Antidepressants such as escitalopram, sertraline, and fluoxetine.
- Benzodiazepines (for treatment of insomnia and anxiety) such as diazepam (Valium®).
4. Diabetes Mellitus.
A. High blood sugar (undiagnosed or uncontrolled diabetes).
Diabetes mellitus refers to the increase in blood sugar (glucose) levels. Patients with undiagnosed diabetes often present with polyuria (frequent urination of large amounts of clear urine without drinking water), thirst sensation, and progressive weight loss.
Also, clear urine may mean uncontrolled diabetes if you are known to be diabetic. High blood sugar diabetes causes polyuria because your body excretes excess sugar through the kidneys.
As the excess blood glucose passes into the urine, it causes the urine volume to increase and the color of pee to pale yellow or clear white (glucose draws more water from the body into the urine).
B. DKA (Diabetic Keto Acidosis).
Peeing a lot of clear urine in a patient with type 1 diabetes (insulin-dependent diabetes typically affecting young adults) may mean impending diabetic ketoacidosis (DKA), a medical emergency.
Consult your doctor if you notice clear, frequent urine without drinking water, especially if it is associated with other symptoms such as shortness of breath, abdominal pain, or vomiting.
C. Diabetic nephropathy.
Long-lasting diabetes (especially if it is poorly controlled) can cause permanent damage to the kidney up to kidney failure.
5. Diabetes insipidus.
The amount of urine excreted is controlled by a hormone secreted called the Antidiuretic hormone (ADH). The hormone is secreted by the pituitary gland inside the brain and acts on a specific receptor in the kidney to prevent excess urine excretion.
Polyuria (excess clear urine) occurs when the ADH hormones are decreased (central diabetes inside) or become ineffective due to defects in the kidney receptors (nephrogenic diabetes insipidus).
Diabetes insipidus produces massive amounts of clear, colorless urine without drinking water.
Significant increase in blood calcium levels occurs with several conditions, such as:
- Parathyroid diseases (as with parathyroid adenomas).
- Certain malignancies, such as multiple myeloma and bone tumors.
- Vitamin D overdose (vitamin D intoxication).
- Medications such as thiazide diuretics, lithium, theophylline, etc.
- Other endocrinal diseases such as acromegaly, adrenal insufficiency, pheochromocytoma, etc.
Patients with severe hypercalcemia typically present with increased urine, which is typically colorless or clear.
Other symptoms of hypercalcemia:
- Thirst sensation.
- Kidney stones.
- Anorexia, nausea, vomiting.
- Decreased concentration, confusion, and maybe coma in severe cases.
- Unexplained fatigue and headache.
- Irregular or slow heartbeats.
- Increased blood pressure.
- Symptoms of the primary cause such as bone pain.
7. Other less frequent causes.
The kidney is more active during pregnancy, and your overall body fluids increase, with a subsequent increase in urine filtration through the kidney (glomerular filtration rate increases by about 50% during pregnancy). This effect (colorless clear urine without drinking water) is more prevalent in the last trimester of pregnancy.
B. Kidney failure.
Patients with acute or chronic kidney failure and during the healing stage of acute kidney injury may develop polyuria (large volume, clear or water-like urine).
A common acute kidney condition called acute tubular necrosis (ATN) may present with scanty urine followed by large amounts of clear, colorless urine (the healing stage).
C. Cushing’s syndrome.
Cushing’s disease is typically caused by an adrenal gland tumor secreting excess corticosteroids. Patients with Cushing’s disease usually have polyuria and clear urine.
D. Excess IV fluids.
Intravenous fluid taken in the hospital or emergency room, such as Saline, Ringer’s lactate, Glucose, and mannitol, may induce polyuria leading to clear urine without drinking.
When to worry?
See a doctor for clear urine if it is associated with one or more of the following:
- Polyuria (large urine volume) is persistent for several days without excess fluid intake.
- Persistent clear urine for days or weeks.
- Recurrent thirst sensation.
- Burning urination or presence of urethral or kidney pain.
- Foamy urine.
- Abdominal pain, nausea, or vomiting.
- Unexplained hunger (polyphagia).
- Unexplained weight loss.