Chlorthalidone 25mg Tablets

Chlorthalidone is a phthalimidine derivative, a long-acting sulfonamide diuretic. It acts primarily in the cortical diluting segment of the ascending limb of the loop of Henle and the early distal convoluted tubule, where it inhibits the reabsorption of sodium and chloride ions. This increases the excretion of sodium, chloride, and water, leading to diuresis. It also increases the excretion of potassium and magnesium and decreases the excretion of calcium and uric acid. Its antihypertensive effect is thought to be due to a reduction in plasma volume and extracellular fluid, and possibly a direct vasodilatory effect.

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 immediately or seek emergency medical attention:

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
+ Unable to pass urine or changes in urine output
+ Dry mouth
+ Dry eyes
+ Severe stomach upset or vomiting
Signs of kidney problems, such as:
+ Unable to pass urine
+ 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, 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.

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, such as foods or drugs. 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 drugs or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:

All prescription and over-the-counter medications you are currently taking
Any natural products or vitamins you are using
* Your complete medical history, including any health problems you have or have had in the past

Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. This will help prevent any potential interactions or adverse effects.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure they are aware of any potential interactions or effects.

To minimize the risk of accidents, avoid driving and other activities that require alertness until you understand how this medication affects you. When getting up from a sitting or lying position, rise slowly to reduce the likelihood of dizziness or fainting. Be cautious when climbing stairs.

Regularly check your blood pressure as instructed by your healthcare provider. This medication may cause elevated cholesterol and triglyceride levels, so it is crucial to discuss this with your doctor.

Follow your doctor's instructions for blood work and laboratory tests, as this medication may affect certain test results. Inform all your healthcare providers and laboratory personnel that you are taking this medication.

Before consuming alcohol, marijuana, or other cannabis products, or using prescription or over-the-counter (OTC) medications that may cause drowsiness, consult with your doctor. If you have diabetes, closely monitor your blood sugar levels, as this medication can cause symptoms such as confusion, drowsiness, increased thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath. Report any of these symptoms to your doctor.

If you have high blood pressure, consult with your doctor before taking OTC products that may increase blood pressure, such as cough or cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, or certain natural products.

This medication is a potent diuretic, which can lead to excessive loss of water and electrolytes (like potassium) in the blood. Your doctor will closely monitor you and adjust the dosage as needed to prevent severe health complications.

Be aware of the potential for gout attacks, and if you are on a low-sodium or sodium-free diet, discuss this with your doctor. This medication may increase your sensitivity to the sun, so take precautions when exposed to sunlight and report any unusual sunburn to your doctor.

If you are pregnant or plan to become pregnant, consult with your doctor to discuss the benefits and risks of using this medication during pregnancy.

• Anuria
• Hypersensitivity to chlorthalidone or other sulfonamide-derived drugs

• Lithium (increased lithium toxicity due to decreased renal clearance)
• Nonsteroidal Anti-inflammatory Drugs (NSAIDs) (reduced diuretic and antihypertensive effects)
• Digoxin (increased risk of digoxin toxicity due to hypokalemia)
• Corticosteroids (increased risk of hypokalemia)
• Other Antihypertensives (additive hypotensive effects)
• Amphotericin B (increased risk of hypokalemia)

• Antidiabetic agents (may decrease glucose tolerance, requiring adjustment of antidiabetic dose)
• Cholestyramine, Colestipol (may reduce absorption of chlorthalidone; administer chlorthalidone 1 hour before or 4 hours after these agents)
• Allopurinol (increased risk of hypersensitivity reactions to allopurinol)
• Neuromuscular blocking agents (enhanced effect due to hypokalemia)
• Pressor amines (e.g., norepinephrine) (decreased arterial responsiveness)

• Not typically categorized as minor for drug-drug interactions, but general caution with other medications that affect electrolytes.

• Dizziness or lightheadedness (especially upon standing)
• Muscle cramps or weakness
• Excessive thirst or dry mouth
• Nausea or vomiting
• Fatigue or lethargy
• Irregular heartbeat
• Swelling in ankles or feet (if edema is worsening)
• Signs of gout (joint pain, swelling, redness)

Category C. Chlorthalidone should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Routine use in otherwise healthy pregnant women with mild edema is not recommended as it may lead to reduced placental perfusion.

Excreted in breast milk. Use with caution. May suppress lactation. The American Academy of Pediatrics considers it compatible with breastfeeding, but monitor infant for potential adverse effects (e.g., dehydration, electrolyte imbalance).

Safety and efficacy not fully established in pediatric patients. Use is generally off-label and with caution, typically for hypertension or edema when other agents are not suitable. Dosing is weight-based and requires careful monitoring of fluid and electrolytes.

Elderly patients may be more susceptible to the hypotensive and electrolyte-disturbing effects (e.g., hypokalemia, hyponatremia) of chlorthalidone. Lower initial doses and careful monitoring are recommended. Renal function should be assessed before and during therapy.

• Chlorthalidone has a very long half-life (40-60 hours), allowing for once-daily dosing and providing sustained blood pressure control.
• It is often preferred over hydrochlorothiazide in hypertension guidelines (e.g., JNC 8, ACC/AHA) due to evidence of superior cardiovascular outcome benefits, possibly related to its longer duration of action and higher potency.
• Despite its long half-life, it is typically dosed in the morning to prevent nocturia.
• Hypokalemia is a common side effect; potassium supplementation or co-administration with potassium-sparing diuretics may be necessary, especially in patients at high risk (e.g., on digoxin, with arrhythmias).
• Can cause hyperuricemia and may precipitate gout attacks in susceptible individuals.
• Less effective in patients with severe renal impairment (CrCl < 30 mL/min).

• Other Thiazide Diuretics (e.g., Hydrochlorothiazide, Indapamide)
• Loop Diuretics (e.g., Furosemide, Torsemide, Bumetanide) - for more potent diuresis, especially in renal impairment
• ACE Inhibitors (e.g., Lisinopril, Enalapril)
• Angiotensin Receptor Blockers (ARBs) (e.g., Valsartan, Losartan)
• Calcium Channel Blockers (e.g., Amlodipine, Nifedipine)
• Beta-blockers (e.g., Metoprolol, Carvedilol)
• Potassium-sparing Diuretics (e.g., Spironolactone, Amiloride, Triamterene)

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 medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.