Chlorthalidone is a prescription medication that is used to treat high blood pressure and to treat fluid retention in patients that have congestive heart failure, kidney disorders, cirrhosis of the liver and other conditions. Chlorthalidone is a ‘water pill’ and works by preventing your body from absorbing excess salt.

Make sure to always read the patient information and instructions before using this medication. Always follow your doctor’s directions.

• Take chlorthalidone with food.
• This medication is often taken in the morning. It is advised not to take this medication within four hours of bedtime as it may cause you to urinate more frequently.
• You may need your blood, blood pressure and urine checked regularly while taking this medication.
• If you are taking chlorthalidone for high blood pressure, continue taking this medication even when you feel well.
• Follow your doctor’s directions about drinking liquids. It is important to stay hydrated, but drinking too much fluid may also be harmful.

Tell your doctor and pharmacist:

• About your drug and other allergies.
• If you take any other prescription or over-the-counter medications.
• Your medical history particularly of heart failure, kidney disease, gout, high cholesterol, triglycerides, diabetes or inability to urinate.
• If you are on a low-salt diet.
• If you are pregnant or planning pregnancy. This medication can cause side effects in a baby.

You should also know:

• Do not breast-feed while taking this medication.
• Do not drink alcohol while taking this medication as it can increase the risk of side effects.

Common side effects of chlorthalidone include but are not limited to:

• Low blood pressure.
• Dizziness.
• Kidney problems.
• Signs of an electrolyte imbalance.

Get medical help if you have any of the following side effects of chlorthalidone:

• Feeling lightheaded or like you might pass out.
• Signs of a kidney problem including tiredness, shortness of breath, little or no urination, or swelling in the feet or ankles.
• Signs of low sodium including slurred speech, confusion, vomiting, loss of coordination, severe weakness, headaches, or feeling unsteady.
• Signs of low magnesium including irregular heartbeats, feeling jittery, muscle spasms, muscle cramps, dizziness, coughing, or a choking feeling.
• Signs of low potassium including irregular heartbeats, fluttering in the chest, numbness or tingling, muscle weakness, limp feeling, leg cramps, increased thirst or urination, or constipation.
• Symptoms of an allergic reaction such as difficulty breathing, hives, or swelling in your face, lips, or throat.

What should I do if I miss a dose of chlorthalidone?

If you miss a dose of chlorthalidone, you should take it as soon as you remember. However, if it is almost time for your next dose, then skip your missed dose.

What is the strength of chlorthalidone?

Chlorthalidone is available in strengths of 25mg and 50mg.