Health Library

Clonidine/chlorthalidone (By mouth)

Chlorthalidone (klor-THAL-i-done), Clonidine (KLOE-ni-deen)

Treats high blood pressure. This medicine is a combination of an antihypertensive (blood pressure medicine) and a diuretic (water pill).

Brand Name(s):

Clorpres

When This Medicine Should Not Be Used:

How to Use This Medicine:

Tablet

• Your doctor will tell you how much of this medicine to take and how often. Do not take more medicine or take it more often than your doctor tells you to.
• Carefully follow your doctor's instructions about any special diet. You may need to eat foods that are high in potassium (such as oranges or bananas) to prevent potassium loss while you are using this medicine.

If a dose is missed:

• If you miss a dose or forget to take your medicine, take it as soon as you can. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. If you miss two or more doses in a row, call your doctor right away.
• Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine:

• Store the medicine at room temperature, away from heat, moisture, and direct light.
• Keep all medicine out of the reach of children and never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Make sure your doctor knows if you are also using bepridil (Vascor®), digoxin (Lanoxin®), lithium, mirtazapine (Remeron®), medicine for depression (such as amitriptyline, nortriptyline, Anafranil®, Norpramin®, Pamelor®, Tofranil®, Vivactil®), or other blood pressure medicine (such as atenolol, metoprolol, propranolol, Corgard®, Inderal®, Lopressor®, Toprol®, Tenormin®).
• Make sure your doctor knows if you are using any medicines that make you sleepy (such as sleeping pills, cold and allergy medicine, narcotic pain killers, or sedatives).
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Make sure your doctor knows if you are pregnant or breastfeeding, or if you have heart disease, kidney disease, liver disease, blood vessel disorders, diabetes, gout, lupus, pancreatitis, or a history of mental depression.
• This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
• Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.
• This medicine may make your skin more sensitive to sunlight. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds.
• Make sure any doctor or dentist who treats you knows that you are using this medicine.
• Tell your doctor about any side effects you have after you stop taking the medicine. This includes nervousness, chest pain, pounding heartbeat, trouble sleeping, shaking or trembling of the hands, stomach cramps, or sweating.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Confusion, extreme weakness, seizures
• Dry mouth, increased thirst, muscle cramps, problems urinating, nausea or vomiting
• Lightheadedness or fainting
• Severe diarrhea
• Skin rash or hives
• Slow heartbeat, trouble breathing, feeling cold
• Swelling of feet or lower legs
• Unusual bleeding or bruising
• Yellow eyes or skin

If you notice these less serious side effects, talk with your doctor:

• Constipation or mild diarrhea
• Dry, itching, or burning eyes
• Loss of appetite
• Problems having sex

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024