Amiloride and hydrochlorothiazide

Name: Amiloride and hydrochlorothiazide

How supplied

No. 3385 — Tablets MODURETIC (amiloride and hydrochlorothiazide) are peach-colored, diamond-shaped, scored, compressed tablets, coded MSD 917 on one side and M on the other. Each tablet contains 5 mg of anhydrous amiloride HCl and 50 mg of hydrochlorothiazide. They are supplied as follows:

NDC 0006-0917-68 in bottles of 100.

Storage

Keep container tightly closed. Protect from light, moisture, freezing, -20°C (-4°F) and store at room temperature, 15-30°C (59-86°F).

MERCK & CO., INC., Whitehouse Station, NJ 08889, USA. Issued November 2002

Overdose

No data are available in regard to overdosage in humans. The oral LD50 of the combination drug is 189 and 422 mg/kg for female mice and female rats, respectively. It is not known whether the drug is dialyzable.

No specific information is available on the treatment of overdosage with MODURETIC (amiloride and hydrochlorothiazide) , and no specific antidote is available. Treatment is symptomatic and supportive. Therapy with MODURETIC (amiloride and hydrochlorothiazide) should be discontinued and the patient observed closely. Suggested measures include induction of emesis and/or gastric lavage.

Amiloride HCl: No data are available in regard to overdosage in humans.

The oral LD50 of amiloride HCl (calculated as the base) is 56 mg/kg in mice and 36 to 85 mg/kg in rats, depending on the strain.

The most common signs and symptoms to be expected with overdosage are dehydration and electrolyte imbalance. If hyperkalemia occurs, active measures should be taken to reduce the serum potassium levels.

Hydrochlorothiazide: The oral LD50 of hydrochlorothiazide is greater than 10.0 g/kg in both mice and rats.

The most common signs and symptoms observed are those caused by electrolyte depletion (hypokalemia, hypochloremia, hyponatremia) and dehydration resulting from excessive diuresis. If digitalis has also been administered, hypokalemia may accentuate cardiac arrhythmias.

Amiloride and Hydrochlorothiazide Overview

Amiloride and hydrochlorothiazide is a prescription medication used to treat high blood pressure. Amiloride and hydrochlorothiazide can also be used in patients with heart failure who develop low amounts of potassium in their blood or in whom maintenance of normal potassium levels is considered to be important. 

It is a single product containing 2 medications: amiloride and hydrochlorothiazide. Amiloride belongs to a group of drugs called diuretics ("water pills"). Specifically, it is a "potassium-sparing" diuretic which means that it works by helping the body get rid of excess fluid by increasing the amount of salt and water the kidneys remove from the blood, while still keeping potassium in the body. Hydrochlorothiazide belongs to a group of drugs called thiazide diuretics, which work by stopping reabsorption of salt into your body. This prevents fluid from building up in the body.

This medication comes in tablet form and is typically given once daily with food.

Common side effects of amiloride and hydrochlorothiazide include headache, weakness, and nausea.

Amiloride and hydrochlorothiazide can also cause dizziness and tiredness (fatigue). Do not drive or operate heavy machinery until you know how this mediaction affects you. 

Uses of Amiloride and Hydrochlorothiazide

Amiloride and hydrochlorothiazide is a prescription medication used to treat high blood pressure. Amiloride and hydrochlorothiazide can also be used in patients with heart failure who develop low amounts of potassium in their blood or in whom maintenance of normal potassium levels is considered to be important. 

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information. 

Amiloride and Hydrochlorothiazide Dosage

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

  • your blood pressure
  • previous medications used
  • other medications you are taking
  • how you respond to this medication

The recommended starting dose of amiloride and hydrochlorothiazide to treat high blood pressure and to maintain normal blood levels of potassium in heart failure patients is one 5/50 mg tablet by mouth once daily with food. The dosage may be increased to two 5/50 mg tablets once a day with food, if necessary. More than two tablets a day is usually not needed. 

Precautions While Using amiloride and hydrochlorothiazide

It is very important that your doctor check your progress at regular visits to make sure amiloride and hydrochlorothiazide is working properly and to decide if you should continue to take it. Blood tests may be needed to check for unwanted effects .

Do not take other medicines unless they have been discussed with your doctor. This especially includes potassium supplements or salt substitutes containing potassium .

amiloride and hydrochlorothiazide may increase the amount of potassium in your blood. Check with your doctor right away if you are having abdominal pain; confusion; difficulty breathing; irregular heartbeats; nausea or vomiting; nervousness; numbness or tingling in the hands, feet, or lips; shortness of breath; or weakness or heaviness of the legs .

amiloride and hydrochlorothiazide Side Effects

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:

More common
  • Abdominal pain
  • confusion
  • difficulty breathing
  • irregular heartbeats
  • nausea or vomiting
  • nervousness
  • numbness or tingling in the hands, feet, or lips
  • shortness of breath
  • weakness or heaviness of the legs
Less common
  • Dizziness
  • fainting
  • fast or slow heartbeat
  • labored breathing
  • tightness in the chest
  • wheezing
Rare
  • Ankle, knee, or great toe joint pain
  • arm, back, or jaw pain
  • blistering, peeling, or loosening of the skin
  • bloody or black, tarry stools
  • bloody urine
  • burning while urinating
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain, discomfort, or heaviness
  • chills
  • cloudy urine
  • cold sweats
  • coma
  • constipation
  • convulsions
  • cough
  • cracks in the skin
  • decreased awareness or responsiveness
  • decreased frequency or amount of urine
  • diarrhea
  • difficult or painful urination
  • dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
  • dry mouth
  • fever
  • headache
  • increase in heart rate
  • increased blood pressure
  • increased thirst
  • itching
  • joint pain, stiffness, or swelling
  • lightheadedness
  • loss of appetite
  • loss of heat from the body
  • lower back or side pain
  • muscle pain or cramps
  • pounding heartbeat or pulse
  • rapid breathing
  • red skin lesions, often with a purple center
  • red, irritated eyes
  • red, swollen skin
  • scaly skin
  • severe sleepiness
  • severe stomach pain
  • sore throat
  • sores, ulcers, or white spots in the mouth or on the lips
  • sunken eyes
  • sweating
  • swelling of the face, ankles, hands, fingers, or lower legs
  • troubled breathing
  • unusual tiredness or weakness
  • vomiting of blood or material that looks like coffee grounds
  • weight gain
  • wrinkled skin

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose
  • Drowsiness
  • irritability
  • mood changes
  • pain or weakness in the hands or feet
  • trembling
  • weak pulse

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:

More common
  • Rash
  • weight loss
Less common
  • Leg ache
  • stomach pain
Rare
  • Bad taste
  • bloated, full feeling
  • blurred or loss of vision
  • changes in appetite
  • decreased interest in sexual intercourse
  • discouragement
  • disturbed color perception
  • double vision
  • excess air or gas in the stomach or intestines
  • feeling of constant movement of self or surroundings
  • feeling of warmth
  • feeling sad or empty
  • general feeling of discomfort or illness
  • hair loss or thinning of hair
  • hiccups
  • inability to have or keep an erection
  • increased sweating
  • increased urge to urinate during the night
  • indigestion
  • loss in sexual ability, desire, drive, or performance
  • loss of bladder control
  • loss of interest or pleasure
  • muscle spasm
  • night blindness
  • overbright appearance of lights
  • passing of gas
  • redness of the face, neck, arms, and occasionally upper chest
  • seeing halos around lights
  • sensation of spinning
  • sleepiness
  • sleeplessness
  • stomach fullness or discomfort
  • stuffy nose
  • swelling of the breasts or breast soreness in both females and males
  • trouble concentrating
  • trouble sleeping
  • tunnel vision
  • unable to sleep
  • waking to urinate at night

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.

What are some things I need to know or do while I take Amiloride and Hydrochlorothiazide?

  • Tell all of your health care providers that you take amiloride and hydrochlorothiazide. This includes your doctors, nurses, pharmacists, and dentists.
  • Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine affects you.
  • To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
  • If you have high blood sugar (diabetes), you will need to watch your blood sugar closely.
  • Have your blood pressure checked often. Talk with your doctor.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take amiloride and hydrochlorothiazide.
  • New lupus or lupus that gets worse has happened with drugs like this one. Talk with your doctor.
  • Avoid salt substitutes that have potassium, potassium-sparing diuretics, or potassium products.
  • If you are taking this medicine and have high blood pressure, talk with your doctor before using OTC products that may raise blood pressure. These include cough or cold drugs, diet pills, stimulants, ibuprofen or like products, and some natural products or aids.
  • You may get sunburned more easily. Avoid sun, sunlamps, and tanning beds. Use sunscreen and wear clothing and eyewear that protects you from the sun.
  • Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
  • Tell your doctor if you have too much sweat, fluid loss, throwing up, or loose stools. This may lead to low blood pressure.
  • If you take cholestyramine or colestipol, talk with your pharmacist about how to take them with amiloride and hydrochlorothiazide.
  • Watch for gout attacks.
  • If you are taking lithium, talk with your doctor. You may need to have your blood work checked more closely while you are taking it with this medicine.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using amiloride and hydrochlorothiazide while you are pregnant.

How is this medicine (Amiloride and Hydrochlorothiazide) best taken?

Use this medicine as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take amiloride and hydrochlorothiazide with food.
  • Keep taking this medicine as you have been told by your doctor or other health care provider, even if you feel well.
  • This medicine may cause you to pass urine more often. To keep from having sleep problems, try to take before 6 pm.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

Dietary Considerations

Take with food.

Pregnancy Risk Factor B Pregnancy Considerations

Adverse events have not been observed in animal reproduction studies. See individual agents.

Side effects

MODURETIC (amiloride and hydrochlorothiazide) is usually well tolerated and significant clinical adverse effects have been reported infrequently. The risk of hyperkalemia (serum potassium levels greater than 5.5 mEq per liter) with MODURETIC (amiloride and hydrochlorothiazide) is about 1-2 percent in patients without renal impairment or diabetes mellitus (see WARNINGS). Minor adverse reactions to amiloride HCl have been reported relatively frequently (about 20%) but the relationship of many of the reports to amiloride HCl is uncertain and the overall frequency was similar in hydrochlorothiazide treated groups. Nausea/anorexia, abdominal pain, flatulence, and mild skin rash have been reported and probably are related to amiloride. Other adverse experiences that have been reported with MODURETIC (amiloride and hydrochlorothiazide) are generally those known to be associated with diuresis, thiazide therapy, or with the underlying disease being treated. Clinical trials have not demonstrated that combining amiloride and hydrochlorothiazide increases the risk of adverse reactions over those seen with the individual components.

The adverse reactions for MODURETIC (amiloride and hydrochlorothiazide) listed in the following table have been arranged into two groups: (1) incidence greater than one percent; and (2) incidence one percent or less. The incidence for group (1) was determined from clinical studies conducted in the United States (607 patients treated with MODURETIC (amiloride and hydrochlorothiazide) ). The adverse effects listed in group (2) include reports from the same clinical studies and voluntary reports since marketing. The probability of a causal relationship exists between MODURETIC (amiloride and hydrochlorothiazide) and these adverse reactions, some of which have been reported only rarely.

Incidence > 1% Incidence ≤ 1%
Body as a Whole
   Headache**
   Weakness**
   Fatigue/tiredness
Malaise
Chest pain
Back pain
Syncope
Cardiovascular
Arrhythmia
Tachycardia
Digitalis toxicity
Orthostatic hypotension
Angina pectoris
Digestive
   Nausea/anorexia**
   Diarrhea
   Gastrointestinal pain
   Abdominal pain
Constipation
GI bleeding
GI disturbance
Appetite changes
Abdominal fullness
Hiccups
Thirst
Vomiting
Anorexia
Flatulence
Metabolic
   Elevated serum potassium levels ( > 5.5 mEq per liter)***
Gout
Dehydration
Symptomatic hyponatremiat
Musculoskeletal
   Leg ache
Muscle cramps/spasm
Joint pain
   Nervous
   Dizziness**
Paresthesia/numbness
Stupor
Vertigo
Psychiatric
   None
Insomnia
Nervousness
Depression Sleepiness
Mental confusion
Respiratory
   Dyspnea
None
Skin
   Rash**
   Pruritus
Flushing
Diaphoresis
Erythema multiforme including
Stevens-Johnson syndrome
Exfoliative dermatitis including toxic epidermal necrolysis
Alopecia
Special Senses
   None
Bad taste
Visual disturbance
Nasal congestion
Urogenital
   None
Impotence Nocturia Dysuria Incontinence
Renal dysfunction including renal failure Gynecomastia
** Reactions occurring in 3% to 8% of patients treated with MODURETIC (amiloride and hydrochlorothiazide) . (Those reactions occurring in less than 3% of the patients are unmarked.)
***See WARNINGS.
†See PRECAUTIONS.

Other adverse reactions that have been reported with the individual components and within each category are listed in order of decreasing severity:

Amiloride

Body as a Whole: Painful extremities, neck/shoulder ache, fatigability; Cardiovascular: Palpitation; Digestive: Activation of probable pre-existing peptic ulcer, abnormal liver function, jaundice, dyspepsia, heartburn; Hematologic: Aplastic anemia, neutropenia; Integumentary: Alopecia, itching, dry mouth; Nervous System/Psychiatric: Encephalopathy, tremors, decreased libido; Respiratory: Shortness of breath, cough; Special Senses: Increased intraocular pressure, tinnitus; Urogenital: Bladder spasms, polyuria, urinary frequency.

Hydrochlorothiazide

Digestive: Pancreatitis, jaundice (intrahepatic cholestatic jaundice), sialadenitis, cramping, gastric irritation; Hematologic: Aplastic anemia, agranulocytosis, leukopenia, hemolytic anemia, thrombocytopenia; Hypersensitivity: Anaphylactic reactions, necrotizing angiitis (vasculitis, cutaneous vasculitis), respiratory distress including pneumonitis and pulmonary edema, photosensitivity, fever, urticaria, purpura; Metabolic: Electrolyte imbalance (see PRECAUTIONS), hyperglycemia, glycosuria, hyperuricemia; Nervous System/Psychiatric: Restlessness; Special Senses: Transient blurred vision, xanthopsia; Urogenital: Interstitial nephritis (see WARNINGS).

Read the entire FDA prescribing information for Moduretic (Amiloride and Hydrochlorothiazide)

Read More »

For the Consumer

Applies to amiloride / hydrochlorothiazide: oral tablet

Along with its needed effects, amiloride / hydrochlorothiazide 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 while taking amiloride / hydrochlorothiazide:

More common
  • Abdominal pain
  • confusion
  • difficulty breathing
  • irregular heartbeats
  • nausea or vomiting
  • nervousness
  • numbness or tingling in the hands, feet, or lips
  • shortness of breath
  • weakness or heaviness of the legs
Less common
  • Dizziness
  • fainting
  • fast or slow heartbeat
  • labored breathing
  • tightness in the chest
  • wheezing
Rare
  • Ankle, knee, or great toe joint pain
  • arm, back, or jaw pain
  • blistering, peeling, or loosening of the skin
  • bloody or black, tarry stools
  • bloody urine
  • burning while urinating
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain, discomfort, or heaviness
  • chills
  • cloudy urine
  • cold sweats
  • coma
  • constipation
  • convulsions
  • cough
  • cracks in the skin
  • decreased awareness or responsiveness
  • decreased frequency or amount of urine
  • diarrhea
  • difficult or painful urination
  • dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
  • dry mouth
  • fever
  • headache
  • increase in heart rate
  • increased blood pressure
  • increased thirst
  • itching
  • joint pain, stiffness, or swelling
  • lightheadedness
  • loss of appetite
  • loss of heat from the body
  • lower back or side pain
  • muscle pain or cramps
  • pounding heartbeat or pulse
  • rapid breathing
  • red skin lesions, often with a purple center
  • red, irritated eyes
  • red, swollen skin
  • scaly skin
  • severe sleepiness
  • severe stomach pain
  • sore throat
  • sores, ulcers, or white spots in the mouth or on the lips
  • sunken eyes
  • sweating
  • swelling of the face, ankles, hands, fingers, or lower legs
  • troubled breathing
  • unusual tiredness or weakness
  • vomiting of blood or material that looks like coffee grounds
  • weight gain
  • wrinkled skin

Get emergency help immediately if any of the following symptoms of overdose occur while taking amiloride / hydrochlorothiazide:

Symptoms of overdose
  • Drowsiness
  • irritability
  • mood changes
  • pain or weakness in the hands or feet
  • trembling
  • weak pulse

Some side effects of amiloride / hydrochlorothiazide 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:

More common
  • Rash
  • weight loss
Less common
  • Leg ache
  • stomach pain
Rare
  • Bad taste
  • bloated, full feeling
  • blurred or loss of vision
  • changes in appetite
  • decreased interest in sexual intercourse
  • discouragement
  • disturbed color perception
  • double vision
  • excess air or gas in the stomach or intestines
  • feeling of constant movement of self or surroundings
  • feeling of warmth
  • feeling sad or empty
  • general feeling of discomfort or illness
  • hair loss or thinning of hair
  • hiccups
  • inability to have or keep an erection
  • increased sweating
  • increased urge to urinate during the night
  • indigestion
  • loss in sexual ability, desire, drive, or performance
  • loss of bladder control
  • loss of interest or pleasure
  • muscle spasm
  • night blindness
  • overbright appearance of lights
  • passing of gas
  • redness of the face, neck, arms, and occasionally upper chest
  • seeing halos around lights
  • sensation of spinning
  • sleepiness
  • sleeplessness
  • stomach fullness or discomfort
  • stuffy nose
  • swelling of the breasts or breast soreness in both females and males
  • trouble concentrating
  • trouble sleeping
  • tunnel vision
  • unable to sleep
  • waking to urinate at night

For Healthcare Professionals

Applies to amiloride / hydrochlorothiazide: oral tablet

General

The most common adverse reactions were headache, weakness, nausea/anorexia, dizziness, and rash.[Ref]

Gastrointestinal

Common (1% to 10%): Nausea/anorexia, diarrhea, gastrointestinal pain, abdominal pain
Frequency not reported: Constipation, gastrointestinal bleeding, gastrointestinal disturbance, abdominal fullness, vomiting, flatulence

Amiloride:
Frequency not reported: Activation of probable preexisting peptic ulcer, dyspepsia, heartburn, dry mouth

Hydrochlorothiazide:
Frequency not reported: Pancreatitis, sialadenitis, cramping, gastric irritation[Ref]

Dermatologic

Common (1% to 10%): Rash, pruritus
Frequency not reported: Diaphoresis, erythema multiforme, Stevens-Johnson syndrome, exfoliative dermatitis, toxic epidermal necrolysis, alopecia

Amiloride:
Frequency not reported: Alopecia, itching, diaphoresis

Hydrochlorothiazide:
Frequency not reported: Cutaneous vasculitis, photosensitivity, urticaria, purpura, toxic epidermal necrolysis[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness
Frequency not reported: Syncope, paresthesia/numbness, vertigo, stupor, sleepiness, bad taste

Amiloride:
Frequency not reported: Encephalopathy, tremors, tinnitus, somnolence[Ref]

Other

Common (1% to 10%): Weakness, fatigue/tiredness
Frequency not reported: Malaise, chest pain, digitalis toxicity, gynecomastia

Amiloride:
Frequency not reported: Fatigability

Hydrochlorothiazide:
Frequency not reported: Fever[Ref]

Metabolic

Common (1% to 10%): Serum potassium greater than 5.5 mEq/L
Frequency not reported: Appetite changes, anorexia, thirst, gout, dehydration, symptomatic hyponatremia, electrolyte imbalance, hyponatremia

Hydrochlorothiazide:
Frequency not reported: Electrolyte imbalance, hyperglycemia, hyperuricemia, hypokalemia[Ref]

Cardiovascular

Common (1% to 10%): Arrhythmia
Frequency not reported: Tachycardia, orthostatic hypotension, angina pectoris, flushing

Amiloride:
Frequency not reported: Palpitation, partial heart block increased to complete heart block

Hydrochlorothiazide:
Frequency not reported: Vasculitis[Ref]

Musculoskeletal

Common (1% to 10%): Leg ache
Frequency not reported: Back pain, muscle cramps/spasm, joint pain

Amiloride:
Frequency not reported: Painful extremities, neck/shoulder ache[Ref]

Respiratory

Common (1% to 10%): Dyspnea
Frequency not reported: Hiccups, nasal congestion

Amiloride:
Frequency not reported: Shortness of breath, cough

Hydrochlorothiazide:
Frequency not reported: Respiratory distress, pneumonitis, pulmonary edema[Ref]

Genitourinary

Frequency not reported: Impotence, nocturia, dysuria, incontinence

Amiloride:
Frequency not reported: Bladder spasm, polyuria, urinary frequency

Hydrochlorothiazide:
Frequency not reported: Glycosuria[Ref]

Psychiatric

Frequency not reported: Insomnia, nervousness, depression, mental confusion

Amiloride:
Frequency not reported: Libido decreased

Hydrochlorothiazide:
Frequency not reported: Restlessness[Ref]

Renal

Frequency not reported: Renal dysfunction, renal failure

Hydrochlorothiazide:
Frequency not reported: Interstitial nephritis[Ref]

Ocular

Frequency not reported: Visual disturbance

Amiloride:
Frequency not reported: Intraocular pressure increased

Hydrochlorothiazide:
Frequency not reported: Transient blurred vision, xanthopsia[Ref]

Immunologic

Frequency not reported: Anaphylactic reaction

Hydrochlorothiazide:
Frequency not reported: Anaphylactic reaction[Ref]

Hematologic

Amiloride:
Frequency not reported: Aplastic anemia, neutropenia

Hydrochlorothiazide:
Frequency not reported: Aplastic anemia, agranulocytosis, leukopenia, hemolytic anemia, thrombocytopenia[Ref]

Hepatic

Amiloride:
Frequency not reported: Abnormal liver function, jaundice

Hydrochlorothiazide:
Frequency not reported: Intrahepatic cholestatic jaundice[Ref]

Some side effects of amiloride / hydrochlorothiazide may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Usual Adult Dose for Hypertension

Initial dose: Amiloride 5 mg-Hydrochlorothiazide 50 mg orally once a day or in divided doses
Maintenance dose: Amiloride 5 to 10 mg-Hydrochlorothiazide 50 to 100 mg orally once a day or in divided doses

Comments:
-Doses greater than amiloride 10 mg-hydrochlorothiazide 100 mg per day are usually not needed and there is no controlled data with such doses.
-Hydrochlorothiazide can be given at doses of 12.5 to 50 mg per day when used alone.
-Patients usually do not require more than hydrochlorothiazide 50 mg per day when combined with other antihypertensive agents.

Use: Treatment of patients with hypertension or congestive heart failure who develop hypokalemia when thiazides or other kaliuretic diuretics are used alone, or in whom maintenance of normal serum potassium levels is considered to be clinically important (e.g., digitalized patients or patients with significant cardiac arrhythmias).

Liver Dose Adjustments

Use with caution

Precautions

US BOXED WARNING:
-HYPERKALEMIA: Like other potassium-conserving diuretic combinations, amiloride and hydrochlorothiazide may cause hyperkalemia (serum potassium levels greater than 5.5 mEq/L). In patients without renal impairment or diabetes mellitus, the risk of hyperkalemia with this combination product is about 1% to 2%. This risk is higher in patients with renal impairment or diabetes mellitus (even without recognized diabetic nephropathy). Since hyperkalemia is potentially fatal if uncorrected, it is essential to monitor serum potassium levels carefully in any patient receiving amiloride hydrochloride and hydrochlorothiazide, particularly during treatment initiation, dose adjustments, and any illness that could affect renal function.

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

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