Chlorothiazide (Oral)

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

Chlorothiazide is also used on its own or with other medicines to treat high blood pressure (hypertension). High blood pressure increases the workload on the heart and arteries. If it lasts for a long time, the heart and arteries may not work properly. This can harm the blood vessels in the brain, heart, and kidneys, leading to a stroke, heart failure, or kidney failure. High blood pressure may also raise the risk of heart attacks. Controlling blood pressure may help reduce the chances of these problems.

Chlorothiazide is a thiazide diuretic (water pill). It decreases the amount of water in the body by increasing urine flow, which helps lower blood pressure and eliminate excess fluid (edema).

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

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

Check with your doctor right away if you have any of the following symptoms while taking this medicine: convulsions or seizures; decreased urine; drowsiness; dry mouth; excessive thirst; muscle pains or cramps; nausea or vomiting; increased heart rate or pulse; or unusual tiredness or weakness. These may be symptoms of a condition called hypokalemia or low potassium.

This medicine may cause some people to feel 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.

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests (e.g., tests for parathyroid function) may be affected by this medicine.

In deciding to use a medicine, you and your doctor will weigh the risks of taking the medicine against the benefits it may provide. For this medicine, the following points should be considered:

Allergies

Inform your doctor if you have ever had an unusual or allergic reaction to this medicine or any other medicines. Also let your healthcare professional know about any other allergies you have, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Research on how chlorothiazide affects children has not been done. However, no pediatric-specific problems that would limit the use of this medicine in children are expected, and no problems have been documented so far.

Geriatric

Studies conducted so far have not shown any geriatric-specific problems that would limit the usefulness of chlorothiazide in older adults. However, older patients are more likely to have age-related liver, kidney, or heart issues, which may require a dose adjustment for those taking chlorothiazide.

Breast Feeding

Studies indicate that this medication may change milk production or composition. If an alternative to this medication is not prescribed, you should watch the infant for side effects and ensure they are getting enough milk.

Interactions with Medicines

While some medicines should not be used together, in other cases, two different medicines may be combined even if an interaction might occur. In these situations, your doctor may adjust the dose or take other precautions. It is especially important for your healthcare professional to know if you are taking any of the medicines listed below. The following interactions have been chosen based on their potential importance and may not include all possible interactions.

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

• Acarbose
• Aceclofenac
• Acemetacin
• Acetyldigoxin
• Albiglutide
• Albuterol
• Alogliptin
• Amphetamine
• Amtolmetin Guacil
• Arsenic Trioxide
• Aspirin
• Benzphetamine
• Bepridil
• Bromfenac
• Bromocriptine
• Bufexamac
• Buprenorphine
• Canagliflozin
• Celecoxib
• Chlorpropamide
• Choline Salicylate
• Clonixin
• Codeine
• Dapagliflozin
• Deslanoside
• Desmopressin
• Dexibuprofen
• Dexketoprofen
• Dextroamphetamine
• Diclofenac
• Diflunisal
• Digitalis
• Digitoxin
• Digoxin
• Dipyrone
• Dofetilide
• 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
• Linagliptin
• Liraglutide
• Lisdexamfetamine
• Lithium
• Lixisenatide
• Lornoxicam
• Loxoprofen
• Lumiracoxib
• Meclofenamate
• Mefenamic Acid
• Meloxicam
• Methamphetamine
• Metildigoxin
• Miglitol
• Morniflumate
• Nabumetone
• Naproxen
• Nateglinide
• Nepafenac
• Niflumic Acid
• Nimesulide
• Nimesulide Beta Cyclodextrin
• Oxaprozin
• Oxyphenbutazone
• Parecoxib
• Phenylbutazone
• Piketoprofen
• Pioglitazone
• Piroxicam
• Porfimer
• Pramlintide
• Proglumetacin
• Propyphenazone
• Proquazone
• Repaglinide
• Rofecoxib
• Rosiglitazone
• Salicylic Acid
• Salsalate
• Saxagliptin
• Sitagliptin
• Sodium Salicylate
• Sulindac
• Tapentadol
• Tenoxicam
• Tiaprofenic Acid
• Tolazamide
• Tolbutamide
• Tolfenamic Acid
• Tolmetin
• Valdecoxib
• Vildagliptin

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both drugs may be the best option for you. If both medicines are prescribed together, your doctor may adjust the dose or frequency of use for one or both medicines.

• Aminolevulinic Acid
• Calcium
• Ginkgo
• Gossypol
• Licorice

Interactions with Food/Tobacco/Alcohol

Some medicines should not be taken around the time of eating food or certain types of food due to possible interactions. Using alcohol or tobacco with some medicines may also cause interactions. Discuss with your healthcare professional about using your medicine with food, alcohol, or tobacco.

Other Medical Problems

Other medical issues may affect the use of this medicine. Make sure to inform your doctor about any other medical problems you have, especially:

• Anuria (not able to form urine)—Should not be used in patients with this condition.

• Asthma or
• Diabetes or
• Gout or
• Hypercalcemia (high calcium in the blood) or
• Hypercholesterolemia (high cholesterol in the blood) or
• Hyperuricemia (high uric acid in the blood) or
• Hypochloremia (low chloride 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
• Liver disease or
• Systemic lupus erythematosus—Use with caution. This medicine may worsen these conditions.

• Kidney disease—Use with caution. The effects of the medicine may be stronger because the medicine is removed from the body more slowly.

Along with its necessary effects, a medicine may cause some unwanted effects. Not all of these side effects may occur, but if they do, they may require medical attention.

Check with your doctor right away if any of the following side effects happen:

Incidence not known

• Abdominal or stomach pain
• back, leg, or stomach pains
• black, tarry stools
• bleeding gums
• blistering, peeling, or loosening of skin
• bloating
• blood in urine or stools
• bloody urine
• blue lips and fingernails
• blurred vision
• burning, crawling, itching, numbness, prickling, "pins and needles," or tingling feelings
• chest pain
• chills
• clay-colored stools
• cloudy urine
• cold sweats
• confusion
• constipation
• cough or hoarseness
• coughing that sometimes produces a pink frothy sputum
• coughing up blood
• cracks in the skin
• darkened urine
• decrease in urine output or decrease in urine-concentrating ability
• decreased frequency or amount of urine
• diarrhea
• difficult, fast, or noisy breathing, sometimes with wheezing
• difficulty swallowing
• dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
• dry mouth
• fast or irregular heartbeat
• fever
• flushed, dry skin
• fruit-like breath odor
• general body swelling
• general feeling of discomfort or illness
• general feeling of tiredness or weakness
• greatly decreased frequency of urination or amount of urine
• headache
• hives
• increased blood pressure
• increased hunger
• increased sweating
• increased thirst
• increased urination
• indigestion
• itching
• joint pain, stiffness, or swelling
• loss of appetite
• loss of heat from the body
• lower back or side pain
• muscle cramps or pain
• nausea or vomiting
• nosebleeds
• numbness, tingling, pain, or weakness in hands or feet
• pain in joints or muscles
• painful or difficult urination
• pains in stomach, side, or abdomen, possibly radiating to the back
• pale skin
• pinpoint red spots on skin
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• rash
• red, irritated eyes
• red skin lesions, often with a purple center
• red, swollen skin
• redness, soreness, or itching skin
• scaly skin
• seizures
• shortness of breath
• sore throat
• sores, ulcers, or white spots on lips or in mouth
• sores, welting, or blisters
• sugar in the urine
• swelling of face, fingers, legs, ankles, feet, or lower legs
• swollen or painful glands
• tenderness of salivary glands
• thickening of bronchial secretions
• tightness in chest
• trembling
• troubled breathing
• unpleasant breath odor
• unusual bleeding or bruising
• unusual tiredness or weakness
• unusual weight loss
• vomiting of blood
• weakness and heaviness of legs
• weight gain
• wheezing
• yellow eyes or skin

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

Incidence not known

• Cramping
• decreased interest in sexual intercourse
• difficulty having a bowel movement (stool)
• feeling of constant movement of self or surroundings
• hair loss, thinning of hair
• inability to have or keep an erection
• increased sensitivity of skin to sunlight
• loss in sexual ability, desire, drive, or performance
• muscle spasm
• pinpoint red or purple spots on skin
• redness or other discoloration of 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.

In the U.S.

• Diuril

Available Dosage Forms:

• Suspension
• Tablet

Therapeutic Class: Cardiovascular Agent

Pharmacologic Class: Diuretic

Chemical Class: Thiazide

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 patients 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.

This medicine will not cure your high blood pressure, but it does help control it. You must continue to receive 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.

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 fluid retention (edema): For oral dosage forms (suspension): Adults—The usual dose is 10 to 20 milliliters (mL) once or twice a day. Your doctor may adjust how often you take your dose. Children—Dose is based on body weight and must be determined by your doctor. For oral dosage forms (tablets): Adults—The usual dose is 500 to 1000 milligrams (mg) once or twice a day. Your doctor may adjust how often you take your dose. Children—Dose is based on body weight and must be determined by your doctor.
• For high blood pressure: For oral dosage forms (suspension): Adults—The usual dose is 10 to 20 milliliters (mL) once a day as a single dose or in divided doses. Your doctor may adjust your dose if needed. Children—Dose is based on body weight and must be determined by your doctor. For oral dosage forms (tablets): Adults—The usual dose is 500 to 1000 milligrams (mg) once a day as a single dose or in divided doses. Your doctor may adjust your dose if needed. Children—Dose is based on body weight and 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.

• Should you use a diuretic with diazoxide?