Why Am I So Thirsty Even After Drinking Water? 7 Causes

1. Dehydration

Dehydration can occur when you sweat too much, whether through vigorous exercise or too much sun exposure. It can also be caused by diarrhea and vomiting, leading to the loss of water and electrolytes from the body. Signs of dehydration include excessive thirst as well as:

• Dry skin, eyes, and mouth
• Tiredness
• Dizziness
• Nausea

2. Diabetes

Diabetes can cause polydipsia (excessive thirst) and polyuria (increased frequency of urination). When sugar levels become very high, your body tries to remove it through urine. This glucose-rich urine takes water along with it, which causes people with diabetes to urinate frequently. This can make you feel thirsty all the time.

3. Diabetic ketoacidosis (DKA)

When someone has diabetes and glucose cannot enter the cells to provide energy, fats are broken down into ketones for energy. When excess fats are used for this purpose, there is an excess buildup of ketones in the blood. Ketones cause the blood to become acidic and result in DKA, which can cause the affected person to urinate more and feel thirsty more often than usual. Other signs and symptoms include:

• Fruity or acetone smell on the breath
• Dry or flushed skin
• Abdominal pain
• Difficulty breathing
• Nausea and vomiting
• Tiredness
• Confusion
• Difficulty concentrating
• Dizziness
• Loss of consciousness
• Coma

DKA is a life-threatening condition that requires emergency medical help. Emergency medical treatment involves replenishing the body with fluids administered intravenously and bringing blood sugar levels down by administering insulin. Blood sugar testing and urine ketone testing kits are available over the counter that can help you monitor your blood sugar level and ketone levels at home.

4. Pregnancy

Feeling thirsty most of the time and feeling the need to pee often are two common signs of pregnancy. However, since these can also be signs of gestational diabetes, consult your doctor and screen yourself for diabetes if you think you are at risk.

5. Medications

Excessive thirst can be a side effect of certain medications:

• Anticholinergics (class of medications used for a wide variety of illnesses including diarrhea, asthma, and Parkinson’s disease)
• Demeclocycline (antibiotic used for bacterial infections)
• Diuretics (class of medications given to reduce body swelling and for hypertension)
• Phenothiazines (class of medications given for convulsions)
• Lithium (mood-stabilizer given for mental disorders such as mania)
• Antipsychotics
• Antidepressants 
• Alpha agonists (class of medications given for hypertension and ADHD)
• SGLT2 inhibitors (a type of diabetes medication)
• Steroids

If you are on these medications and begin to feel thirstier even after drinking plenty of fluids, do not stop these medications until consulting your doctor. Your doctor may prescribe another medication.

6. Diabetes insipidus

Polydipsia may be a symptom of diabetes insipidus. Unlike diabetes mellitus, diabetes insipidus is a rare condition that affects 1 in 25,000 people and is caused by a problem with the production of the hormone vasopressin. Vasopressin is secreted by the pituitary gland and promotes water retention in the kidneys. If you have diabetes insipidus, you may pass large volumes of clear, odorless urine. According to the National Institute of Diabetes and Digestive and Kidney Diseases, your urine output may fall anywhere between 3.4-22.7 liters a day. Normally, a healthy person produces 800-2,000 milliliters of urine a day with typical fluid intake of about 2 liters per day. 

7. Psychogenic polydipsia

Psychogenic polydipsia, also known as primary polydipsia, is a form of polydipsia characterized by excessive fluid intake without any physiological stimuli to drink. It is caused by psychiatric disorders, often schizophrenia, which is often accompanied by the feeling of dry mouth.