Hygroton 25mg Tablets
It is used to treat high blood pressure.It is used to get rid of extra fluid.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihypertensive, Diuretic
Pharmacologic Class
Thiazide-like Diuretic
Pregnancy Category
B
FDA Approved
Mar 1960
DEA Schedule
Not Controlled
Overview
What is this medicine?
Chlorthalidone is a 'water pill' (diuretic) that helps your body get rid of extra salt and water. This helps to lower your blood pressure and reduce swelling (edema). It works by making your kidneys remove more sodium and water from your blood.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take this medication with food as directed. Be aware that it may increase your urine production, so try to avoid taking it close to bedtime to minimize sleep disturbances. Continue taking this medication as prescribed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry place, avoiding bathrooms. Keep all medications in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take this medication with food as directed. Be aware that it may increase your urine production, so try to avoid taking it close to bedtime to minimize sleep disturbances. Continue taking this medication as prescribed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry place, avoiding bathrooms. Keep all medications in a safe location, out of reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take exactly as prescribed, usually once daily in the morning to avoid nighttime urination.
- Do not stop taking without consulting your doctor, even if you feel well.
- Maintain adequate hydration, especially in hot weather or during exercise, to prevent dehydration.
- Follow a low-sodium diet as advised by your doctor or dietitian.
- Monitor your blood pressure regularly at home if advised by your doctor.
- Avoid excessive alcohol consumption, as it can increase the risk of dizziness and low blood pressure.
- Be aware of symptoms of low potassium (muscle cramps, weakness, irregular heartbeat) and report them to your doctor.
- Limit sun exposure and use sunscreen, as chlorthalidone can increase sensitivity to sunlight.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Hypertension: 25 mg orally once daily. Edema: 25-100 mg orally once daily or every other day.
Dose Range:
12.5 - 100 mg
Condition-Specific Dosing:
hypertension:
Initial: 12.5 mg to 25 mg orally once daily. May increase to 50 mg once daily if needed. Doses above 25 mg generally do not provide additional blood pressure reduction but increase adverse effects.
edema:
Initial: 25 mg to 100 mg orally once daily or every other day. Some patients may require 100-200 mg daily.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established (use generally not recommended or limited to specific conditions under specialist supervision)
Adolescent:
Not established (use generally not recommended or limited to specific conditions under specialist supervision)
Dose Adjustments
Renal Impairment:
Mild:
No dosage adjustment typically needed (CrCl > 50 mL/min).
Moderate:
Use with caution (CrCl 30-50 mL/min). Diuretic effect may be diminished. Consider lower doses.
Severe:
Not recommended or largely ineffective (CrCl < 30 mL/min). Loop diuretics are generally preferred.
Dialysis:
Not removed by dialysis. Use not recommended due to lack of efficacy and potential for accumulation.
Hepatic Impairment:
Mild:
No specific adjustment, but use with caution.
Moderate:
Use with caution. May precipitate hepatic coma in susceptible patients. Monitor fluid and electrolyte balance closely.
Severe:
Contraindicated or use with extreme caution due to risk of hepatic coma.
Pharmacology
Mechanism of Action
Chlorthalidone is a thiazide-like diuretic that acts primarily in the cortical diluting segment of the distal convoluted tubule. It inhibits the reabsorption of sodium and chloride ions by blocking the Na+/Cl- cotransporter (NCC), leading to increased excretion of sodium, chloride, and water. It also increases potassium and magnesium excretion and decreases calcium excretion. Its antihypertensive effect is thought to be due to a reduction in plasma volume and peripheral vascular resistance.
Pharmacokinetics
Absorption:
Bioavailability:
64-65%
Tmax:
2-6 hours
FoodEffect:
Food may slightly increase absorption but is not clinically significant; can be taken with or without food.
Distribution:
Vd:
Approximately 3.9-6.3 L/kg
ProteinBinding:
Approximately 75% (primarily to carbonic anhydrase in red blood cells)
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 40-60 hours (can range from 35 to 70 hours, prolonged in renal impairment)
Clearance:
Not readily available, but primarily renal.
ExcretionRoute:
Renal (primarily unchanged), small amount via bile.
Unchanged:
Approximately 50-70% (renal excretion)
Pharmacodynamics
OnsetOfAction:
2-3 hours
PeakEffect:
2-6 hours
DurationOfAction:
24-72 hours (due to long half-life)
Safety & Warnings
Side Effects
Serious Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of fluid and electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain or weakness
+ Fast or abnormal heartbeat
+ Severe dizziness or fainting
+ Increased thirst
+ Seizures
+ Feeling extremely tired or weak
+ Decreased appetite
+ Inability to urinate or changes in urine output
+ Dry mouth
+ Dry eyes
+ Severe stomach upset or vomiting
Signs of kidney problems, such as:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of pancreatitis (pancreas problems), including:
+ Severe stomach pain
+ Severe back pain
+ Severe stomach upset or vomiting
Abnormal sensations, such as burning, numbness, or tingling
Erectile dysfunction
Restlessness
Yellowing of the skin or eyes
Changes in vision
Fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people experience no side effects or only mild ones. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Dizziness
Fatigue
Weakness
Headache
Constipation
Diarrhea
Stomach upset
Vomiting
Decreased appetite
Stomach cramps
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of fluid and electrolyte problems, including:
+ Mood changes
+ Confusion
+ Muscle pain or weakness
+ Fast or abnormal heartbeat
+ Severe dizziness or fainting
+ Increased thirst
+ Seizures
+ Feeling extremely tired or weak
+ Decreased appetite
+ Inability to urinate or changes in urine output
+ Dry mouth
+ Dry eyes
+ Severe stomach upset or vomiting
Signs of kidney problems, such as:
+ Inability to urinate
+ Changes in urine output
+ Blood in the urine
+ Sudden weight gain
Signs of pancreatitis (pancreas problems), including:
+ Severe stomach pain
+ Severe back pain
+ Severe stomach upset or vomiting
Abnormal sensations, such as burning, numbness, or tingling
Erectile dysfunction
Restlessness
Yellowing of the skin or eyes
Changes in vision
Fever, chills, or sore throat
Unexplained bruising or bleeding
Feeling extremely tired or weak
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people experience no side effects or only mild ones. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Dizziness
Fatigue
Weakness
Headache
Constipation
Diarrhea
Stomach upset
Vomiting
Decreased appetite
Stomach cramps
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or fainting
- Extreme thirst or dry mouth
- Nausea or vomiting
- Unusual tiredness or weakness
- Muscle cramps or spasms
- Irregular or fast heartbeat
- Confusion or lethargy
- Signs of allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
- Sudden joint pain or swelling (signs of gout)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
A known sulfa allergy, as this may affect your ability to take this medication safely.
Any difficulties with urination, as this medication may not be suitable for individuals with certain urinary problems.
If you are breastfeeding, as you should not breastfeed while taking this medication.
Additionally, this medication may interact with other medications or health conditions. To ensure your safety, it is crucial to:
Inform your doctor and pharmacist about all medications you are taking, including prescription and over-the-counter medications, natural products, and vitamins.
Discuss all your health problems with your doctor and pharmacist to determine if it is safe to take this medication.
* Never start, stop, or change the dose of any medication without first consulting your doctor to avoid potential interactions or complications.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
A known sulfa allergy, as this may affect your ability to take this medication safely.
Any difficulties with urination, as this medication may not be suitable for individuals with certain urinary problems.
If you are breastfeeding, as you should not breastfeed while taking this medication.
Additionally, this medication may interact with other medications or health conditions. To ensure your safety, it is crucial to:
Inform your doctor and pharmacist about all medications you are taking, including prescription and over-the-counter medications, natural products, and vitamins.
Discuss all your health problems with your doctor and pharmacist to determine if it is safe to take this medication.
* Never start, stop, or change the dose of any medication without first consulting your doctor to avoid potential interactions or complications.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
To ensure your safety, avoid driving and other activities that require alertness until you understand how this medication affects you. When getting up from a sitting or lying down position, do so slowly to minimize the risk of dizziness or fainting. Be cautious when using stairs.
Follow your doctor's instructions for monitoring your blood pressure. This medication may cause elevated cholesterol and triglyceride levels, so discuss any concerns with your doctor.
Regular blood tests are necessary while taking this medication, as it may impact certain lab results. Inform all your healthcare providers and laboratory personnel that you are taking this medication.
Before consuming alcohol, marijuana, or other substances that may impair your actions, or taking prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
If you have diabetes, closely monitor your blood sugar levels, as this medication can affect them. Be aware of signs of high blood sugar, such as confusion, drowsiness, increased thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath, and report them to your doctor.
If you have high blood pressure, consult your doctor before taking over-the-counter products that may increase blood pressure, including cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
This medication is a potent diuretic, which can lead to excessive loss of water and electrolytes (such as potassium) in the blood, resulting in severe health issues. Your doctor will closely monitor you and adjust the dosage as needed to meet your body's requirements.
Be aware of the risk of gout attacks while taking this medication. If you are on a low-sodium or sodium-free diet, discuss this with your doctor.
This medication may increase your susceptibility to sunburn. Take precautions when exposed to the sun, and inform your doctor if you experience excessive sunburn.
If you are pregnant or plan to become pregnant, discuss the benefits and risks of taking this medication with your doctor.
To ensure your safety, avoid driving and other activities that require alertness until you understand how this medication affects you. When getting up from a sitting or lying down position, do so slowly to minimize the risk of dizziness or fainting. Be cautious when using stairs.
Follow your doctor's instructions for monitoring your blood pressure. This medication may cause elevated cholesterol and triglyceride levels, so discuss any concerns with your doctor.
Regular blood tests are necessary while taking this medication, as it may impact certain lab results. Inform all your healthcare providers and laboratory personnel that you are taking this medication.
Before consuming alcohol, marijuana, or other substances that may impair your actions, or taking prescription or over-the-counter medications that may cause drowsiness, consult with your doctor.
If you have diabetes, closely monitor your blood sugar levels, as this medication can affect them. Be aware of signs of high blood sugar, such as confusion, drowsiness, increased thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath, and report them to your doctor.
If you have high blood pressure, consult your doctor before taking over-the-counter products that may increase blood pressure, including cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
This medication is a potent diuretic, which can lead to excessive loss of water and electrolytes (such as potassium) in the blood, resulting in severe health issues. Your doctor will closely monitor you and adjust the dosage as needed to meet your body's requirements.
Be aware of the risk of gout attacks while taking this medication. If you are on a low-sodium or sodium-free diet, discuss this with your doctor.
This medication may increase your susceptibility to sunburn. Take precautions when exposed to the sun, and inform your doctor if you experience excessive sunburn.
If you are pregnant or plan to become pregnant, discuss the benefits and risks of taking this medication with your doctor.
Overdose Information
Overdose Symptoms:
- Severe dehydration
- Electrolyte imbalance (e.g., severe hypokalemia, hyponatremia)
- Hypotension (very low blood pressure)
- Dizziness, weakness, confusion
- Nausea, vomiting
- Cardiac arrhythmias
What to Do:
Seek immediate medical attention. Call 911 or Poison Control (1-800-222-1222). Treatment is supportive, focusing on fluid and electrolyte replacement and blood pressure management.
Drug Interactions
Contraindicated Interactions
- Anuria
- Known hypersensitivity to chlorthalidone or sulfonamide-derived drugs
Major Interactions
- Lithium (increased lithium toxicity due to decreased renal clearance)
- Nonsteroidal Anti-inflammatory Drugs (NSAIDs) (may reduce diuretic and antihypertensive effects, risk of renal impairment)
- Corticosteroids (increased risk of electrolyte imbalance, particularly hypokalemia)
- Digoxin (increased risk of digoxin toxicity due to hypokalemia)
- Other antihypertensives (additive hypotensive effects)
- Insulin and oral hypoglycemics (may decrease glucose tolerance, requiring dose adjustment)
- Cholestyramine, Colestipol (may reduce absorption of chlorthalidone)
Moderate Interactions
- Alcohol (additive hypotensive effects)
- Barbiturates (additive hypotensive effects)
- Opioids (additive hypotensive effects)
- Norepinephrine (decreased arterial responsiveness to norepinephrine)
- Skeletal muscle relaxants, non-depolarizing (prolonged effect)
- Allopurinol (increased risk of hypersensitivity reactions to allopurinol)
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Serum Electrolytes (Potassium, Sodium, Magnesium, Calcium)
Rationale: To establish baseline levels and identify pre-existing imbalances, as chlorthalidone can cause hypokalemia, hyponatremia, hypomagnesemia, and hypercalcemia.
Timing: Prior to initiation of therapy.
Renal Function (BUN, Serum Creatinine, eGFR)
Rationale: To assess kidney function, as chlorthalidone efficacy is reduced in severe renal impairment and it can worsen renal function in some cases.
Timing: Prior to initiation of therapy.
Blood Pressure
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation of therapy.
Uric Acid
Rationale: Chlorthalidone can increase serum uric acid levels, potentially precipitating gout.
Timing: Prior to initiation of therapy.
Blood Glucose
Rationale: Chlorthalidone can impair glucose tolerance.
Timing: Prior to initiation of therapy, especially in diabetic or pre-diabetic patients.
Routine Monitoring
Serum Electrolytes (Potassium, Sodium, Magnesium)
Frequency: Weekly for the first few weeks, then monthly for 1-2 months, then every 3-6 months or as clinically indicated.
Target: Potassium: 3.5-5.0 mEq/L; Sodium: 135-145 mEq/L; Magnesium: 1.7-2.2 mg/dL
Action Threshold: Potassium < 3.0 mEq/L (consider supplementation or dose reduction); Sodium < 130 mEq/L (investigate cause, consider discontinuation); Magnesium < 1.5 mg/dL (consider supplementation).
Renal Function (BUN, Serum Creatinine)
Frequency: Monthly for 1-2 months, then every 3-6 months or as clinically indicated.
Target: Within normal limits for age/sex.
Action Threshold: Significant increase in creatinine (>20-30% from baseline) or eGFR < 30 mL/min (consider dose reduction or discontinuation).
Blood Pressure
Frequency: Regularly (e.g., weekly initially, then monthly or as per clinical guidelines) until controlled, then every 3-6 months.
Target: As per guideline (e.g., <130/80 mmHg for most adults).
Action Threshold: Persistent uncontrolled hypertension or symptomatic hypotension.
Uric Acid
Frequency: Every 6-12 months or if symptoms of gout develop.
Target: Within normal limits.
Action Threshold: Symptomatic hyperuricemia or gout flare.
Blood Glucose (HbA1c for diabetics)
Frequency: Every 6-12 months or as clinically indicated, more frequently in diabetics.
Target: Within target range for patient.
Action Threshold: Significant increase in blood glucose or worsening glycemic control.
Symptom Monitoring
- Dizziness or lightheadedness (especially upon standing)
- Muscle weakness or cramps
- Excessive thirst or dry mouth
- Nausea or vomiting
- Unusual fatigue or lethargy
- Irregular heartbeat
- Swelling of ankles, feet, or hands (if edema is worsening)
- Symptoms of gout (joint pain, swelling, redness)
- Symptoms of hyperglycemia (increased thirst, urination, fatigue)
Special Patient Groups
Pregnancy
Generally not recommended for routine use in pregnancy for hypertension, as it can reduce plasma volume and placental perfusion. May be considered for specific indications like pulmonary edema, but benefits must outweigh risks. Pregnancy Category B.
Trimester-Specific Risks:
First Trimester:
Limited data, but generally avoided unless essential.
Second Trimester:
Potential for reduced plasma volume and placental perfusion, which could affect fetal growth.
Third Trimester:
Potential for reduced plasma volume and placental perfusion; may cause electrolyte disturbances in the newborn (e.g., thrombocytopenia, jaundice).
Lactation
Excreted into breast milk. Can reduce milk supply. Use with caution. Monitor infant for signs of dehydration or electrolyte imbalance. L3 (Moderately Safe) - use with caution, monitor infant.
Infant Risk:
Low risk of adverse effects in healthy, full-term infants, but potential for dehydration or electrolyte imbalance, especially in premature or jaundiced infants. May decrease milk production.
Pediatric Use
Safety and efficacy not well-established in pediatric patients. Use is generally not recommended or limited to specific conditions under specialist supervision due to potential for electrolyte disturbances and lack of long-term data.
Geriatric Use
Elderly patients may be more sensitive to the effects of chlorthalidone, particularly regarding electrolyte imbalances (hypokalemia, hyponatremia) and orthostatic hypotension. Lower initial doses and careful monitoring are recommended.
Clinical Information
Clinical Pearls
- Chlorthalidone has a longer duration of action and half-life compared to hydrochlorothiazide, making it a preferred thiazide-like diuretic in some hypertension guidelines (e.g., ACC/AHA).
- Administer in the morning to prevent nocturia.
- Monitor electrolytes (especially potassium, sodium, magnesium) closely, particularly during initiation and dose changes.
- Educate patients on symptoms of electrolyte imbalance and dehydration.
- May cause hyperuricemia and precipitate gout attacks; monitor uric acid levels.
- Can cause hyperglycemia; monitor blood glucose, especially in diabetic patients.
- Patients should be advised to use sunscreen and protective clothing due to increased photosensitivity.
Alternative Therapies
- Other thiazide diuretics (e.g., Hydrochlorothiazide, Indapamide)
- Loop diuretics (e.g., Furosemide, Torsemide - for more potent diuresis, especially in renal impairment)
- Potassium-sparing diuretics (e.g., Spironolactone, Amiloride)
- ACE inhibitors (e.g., Lisinopril, Ramipril)
- Angiotensin Receptor Blockers (ARBs) (e.g., Valsartan, Losartan)
- Beta-blockers (e.g., Metoprolol, Atenolol)
- Calcium Channel Blockers (e.g., Amlodipine, Diltiazem)
Cost & Coverage
Average Cost:
Varies widely, typically low cost for generic per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Preferred Generic) on most commercial and Medicare Part D plans.
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the overdose, including the medication taken, the amount, and the time it occurred.