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Chlorthalidone (Oral route)

Pronunciation:

klor-THAL-i-done

Brand Names:

  • Thalitone

Dosage Forms:

  • Tablet

Classifications:

Therapeutic—

Cardiovascular Agent

Pharmacologic—

Diuretic

Chemical—

Thiazide Related

Uses of This Medicine:

Chlorthalidone is used alone or together with other medicines to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Chlorthalidone is also used to treat fluid retention (edema) that is caused by congestive heart failure, severe liver disease (cirrhosis), kidney disease, or treatment with a hormone or steroid medicine.

Chlorthalidone is a diuretic (water pill). It reduces the amount of water in the body by increasing the flow of urine, which helps to lower blood pressure.

This medicine is available only with your doctor's prescription.

Before Using This Medicine:

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children—

Appropriate studies have not been performed on the relationship of age to the effects of chlorthalidone in the pediatric population. Safety and efficacy have not been established.

Older adults—

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of chlorthalidone in the elderly. However, elderly patients are more likely to have age-related kidney disease, which may require caution and an adjustment in the dose for patients receiving chlorthalidone.

Breast-feeding—

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Other medicines—

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Acarbose
  • Aceclofenac
  • Acemetacin
  • Acetyldigoxin
  • Albiglutide
  • Albuterol
  • Alogliptin
  • Amtolmetin Guacil
  • Arsenic Trioxide
  • Aspirin
  • Bepridil
  • Bromfenac
  • Bromocriptine
  • Bufexamac
  • Buprenorphine
  • Canagliflozin
  • Celecoxib
  • Chlorpropamide
  • Choline Salicylate
  • Clonixin
  • Codeine
  • Dapagliflozin
  • Deslanoside
  • Desmopressin
  • Dexibuprofen
  • Dexketoprofen
  • Diclofenac
  • Diflunisal
  • Digitalis
  • Digitoxin
  • Digoxin
  • Dipyrone
  • Dofetilide
  • Droperidol
  • Droxicam
  • Dulaglutide
  • Empagliflozin
  • Etodolac
  • Etofenamate
  • Etoricoxib
  • Exenatide
  • Felbinac
  • Fenoprofen
  • Fepradinol
  • Feprazone
  • Flecainide
  • Floctafenine
  • Flufenamic Acid
  • Flurbiprofen
  • Formoterol
  • Glimepiride
  • Glipizide
  • Glyburide
  • Ibuprofen
  • Indomethacin
  • Insulin
  • Insulin Aspart, Recombinant
  • Insulin Bovine
  • Insulin Degludec
  • Insulin Detemir
  • Insulin Glulisine
  • Ketanserin
  • Ketoprofen
  • Ketorolac
  • Levomethadyl
  • Linagliptin
  • Liraglutide
  • Lithium
  • Lixisenatide
  • Lornoxicam
  • Loxoprofen
  • Lumiracoxib
  • Meclofenamate
  • Mefenamic Acid
  • Meloxicam
  • Methotrexate
  • Metildigoxin
  • Miglitol
  • Morniflumate
  • Nabumetone
  • Naproxen
  • Nateglinide
  • Nepafenac
  • Niflumic Acid
  • Nimesulide
  • Nimesulide Beta Cyclodextrin
  • Oxaprozin
  • Oxyphenbutazone
  • Parecoxib
  • Phenylbutazone
  • Piketoprofen
  • Pioglitazone
  • Piroxicam
  • Pramlintide
  • Proglumetacin
  • Propyphenazone
  • Proquazone
  • Repaglinide
  • Rofecoxib
  • Rosiglitazone
  • Salicylic Acid
  • Salsalate
  • Saxagliptin
  • Sitagliptin
  • Sodium Salicylate
  • Sotalol
  • Sulindac
  • Tapentadol
  • Tenoxicam
  • Tiaprofenic Acid
  • Tolazamide
  • Tolbutamide
  • Tolfenamic Acid
  • Tolmetin
  • Valdecoxib
  • Vildagliptin

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Aminolevulinic Acid
  • Gossypol
  • Licorice
  • Warfarin

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems—

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Anuria (not able to form urine)—Should not be used in patients with this condition.
  • Asthma or
  • Dehydration or
  • Diabetes or
  • Gout or
  • Hypercalcemia (high calcium in the blood) or
  • Hyperlipidemia (high cholesterol or triglycerides in the blood) or
  • Hyperuricemia (high uric acid in the blood) or
  • Hypochloremic alkalosis (low chlorine in the blood) or
  • Hypokalemia (low potassium in the blood) or
  • Hypomagnesemia (low magnesium in the blood) or
  • Hyponatremia (low sodium in the blood) or
  • Hypophosphatemia (low phosphorus in the blood) or
  • Hypotension (low blood pressure) or
  • Hypovolemia (low blood volume) or
  • Kidney failure or
  • Systemic lupus erythematosus—Use with caution. May make these conditions worse.
  • Kidney disease or
  • Liver disease—Use with caution. The effects of the medicine may be increased because of slower removal of the medicine from the body.

Proper Use of This Medicine:

Take this medicine exactly as directed by your doctor to benefit your condition as much as possible. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

To help you remember to take your medicine, try to get into the habit of taking it at the same time each day.

In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium or potassium. Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet.

Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.

Remember that this medicine will not cure your high blood pressure, but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.

This medicine is usually taken in the morning with food.

Dosing—

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For fluid retention (edema):
      • Adults—At first, 50 to 100 milligrams (mg) once a day, or 100 mg once every other day. Your doctor may adjust your dose if needed.
      • Children—Use and dose must be determined by your doctor.
    • For high blood pressure:
      • Adults—
        • Chlorthalidone: At first, 25 milligrams (mg) once a day. Your doctor may adjust your dose if needed.
        • Thalitone®: At first, 15 mg once a day. After 2 weeks, your dose may be increased to 25 mg per day as needed.
      • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions While Using This Medicine:

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. Getting up slowly may help. If the problem continues or gets worse, check with your doctor.

This medicine may cause you to lose more potassium from your body than normal (hypokalemia). Tell your doctor if you become sick with severe or continuing nausea, vomiting, or diarrhea, and drink fluids to prevent getting dehydrated. Check with your doctor right away if you have dry mouth, increased thirst, muscle cramps, or nausea or vomiting.

This medicine may cause some people to become dizzy. Do not drive, use machines, or do anything else that could be dangerous if you are dizzy.

Drinking alcoholic beverages may also make the dizziness worse. While you are taking this medicine, be careful to limit the amount of alcohol you drink.

Do not take other medicines unless they have been discussed with your doctor. This especially includes prescription or nonprescription (over-the-counter) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Incidence not known
Abdominal or stomach pain
black, tarry stools
bleeding gums
blistering, peeling, or loosening of the skin
bloating
blood in the urine or stools
blurred vision
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
chest pain
chills
clay-colored stools
cold sweats
confusion
cough or hoarseness
coughing up blood
darkened urine
diarrhea
difficulty having a bowel movement (stool)
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
dry mouth
fast heartbeat
fever
flushed, dry skin
fruit-like breath odor
general feeling of tiredness or weakness
headache
increased hunger
increased thirst
increased urination
indigestion
itching or skin rash
joint pain, stiffness, or swelling
loss of appetite
lower back or side pain
nausea
pain in the joints or muscles
painful or difficult urination
pains in the stomach, side, or abdomen, possibly radiating to the back
pinpoint red spots on the skin
red, irritated eyes
red skin lesions, often with a purple center
redness, soreness or itching skin
sore throat
sores, ulcers, or white spots on the lips or in the mouth
sores, welting, or blisters
sugar in the urine
sweating
swelling of the feet or lower legs
swollen glands
tightness in the chest
troubled breathing
unpleasant breath odor
unusual bleeding or bruising
unusual tiredness or weakness
unusual weight loss
vomiting
vomiting of blood
weight loss
yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known
Cramping
decreased interest in sexual intercourse
feeling of constant movement of self or surroundings
hives
inability to have or keep an erection
increased sensitivity of the skin to sunlight
loss in sexual ability, desire, drive, or performance
muscle spasm
redness or other discoloration of the skin
restlessness
sensation of spinning
severe sunburn
weakness

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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


Last Updated: 11/16/2023

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

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The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.
All rights reserved.

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