Why is this medicine prescribed?
Chlorthalidone, a is used to treat high blood pressure and fluid retention. Chlorthalidone is in a class of medications called diuretics ('water pills'). It causes the kidneys to get rid of unneeded water and salt from the body into the urine.
High blood pressure is a common condition, and when not treated it can cause damage to the brain, heart, blood vessels, kidneys, and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.
Are there other uses for this medicine?
This medicine may be prescribed for other uses; ask your doctor or pharmacist for more information.
How should this medicine be used?
Chlorthalidone comes as a tablet to take by mouth. It is taken with food once a day or every other day. Take chlorthalidone at around the same time every day, preferably in the morning.
Take chlorthalidone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Chlorthalidone controls high blood pressure but does not cure it. Continue to take chlorthalidone even if you feel well. Do not stop taking chlorthalidone without talking to your doctor.
What special precautions should I follow?
Before taking chlorthalidone,
- tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any other drugs, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking chlorthalidone. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you unable to urinate or have difficulty urinating. Your doctor may tell you not to take chlorthalidone.
- tell your doctor if you have or have ever had diabetes, gout, systemic lupus erythematosus (SLE, a chronic inflammatory condition), high cholesterol, or kidney or liver disease.
- tell your doctor if you are pregnant or plan to become pregnant. If you become pregnant while taking chlorthalidone, call your doctor immediately.
- tell your doctor if you are breastfeeding or plan to breastfeed. You should not breastfeed while you are taking chlorthalidone.
- plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, and sunscreen. Chlorthalidone may make your skin sensitive to sunlight.
- you should know that chlorthalidone may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking chlorthalidone. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
- ask your doctor about the safe use of alcoholic beverages while you are taking chlorthalidone. Alcohol can make the side effects from chlorthalidone worse.
What special dietary instructions should I follow?
Follow your doctor's directions. They may include a low-salt or low-sodium diet, potassium supplements, and increased amounts of potassium-rich foods (e.g., bananas, prunes, raisins, and orange juice) in your diet.
What should I do if I forget to take a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What should I do in case of overdose?
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
Symptoms of overdose may include:
- nausea
- dizziness
- weakness
What side effects can this medicine cause?
Chlorthalidone may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- frequent urination
- dizziness
- upset stomach, nausea, vomiting, diarrhea
- loss of appetite
- headache
If you experience any of the following symptoms, call your doctor immediately:
- thirst; tiredness; drowsiness; restlessness; muscle weakness, pain or cramps; nausea; vomiting; or fast heartbeat
- unusual bleeding or bruising
- rash, itching, hives, or blisters or peeling skin
- difficulty breathing or swallowing
What should I know about storage and disposal of this medication?
Keep this medicine in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information. Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.orgWhat other information should I know?
Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly. Your doctor may order certain lab tests to check your body's response to chlorthalidone.
Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.