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Spironolactone

Generic Name: Spironolactone

Brand Names: Aldactone, CaroSpir

Spironolactone is a potassium-sparing diuretic and aldosterone antagonist used to treat heart failure, high blood pressure, and fluid retention. It is also used to treat hormonal acne and hirsutism in women.

CardiovascularDiureticsHeart FailureDermatologyHormonal

What It's Used For

is prescribed to treat:

Heart failure (reduces mortality and hospitalizations) • High blood pressure (hypertension) • Edema (fluid retention) from various causes • Primary hyperaldosteronism • Cirrhosis with ascites • Nephrotic syndrome • Hormonal acne in women (off-label) • Polycystic ovary syndrome (PCOS) symptoms (off-label) • Hirsutism (excessive hair growth in women) (off-label)

It helps remove excess fluid while retaining potassium.

Side Effects

Common side effects may include:

• Increased urination • Dizziness or lightheadedness • Headache • Nausea or vomiting • Diarrhea or stomach cramps • Drowsiness • Irregular menstrual periods • Breast tenderness or enlargement (in both men and women)

Serious side effects (seek immediate medical attention):

• Signs of high potassium (muscle weakness, slow/irregular heartbeat, severe dizziness) • Severe dehydration (very dry mouth, extreme thirst, muscle cramps) • Signs of electrolyte imbalance • Severe allergic reactions • Unusual bleeding or bruising • Yellowing of skin or eyes (liver problems) • Confusion or mental changes

Additional Information

What is ?

Spironolactone is a unique medication that serves multiple purposes in medicine. Primarily classified as a potassium-sparing diuretic and aldosterone antagonist, it is used to treat heart failure, high blood pressure, and fluid retention. Additionally, due to its anti-androgenic properties, it is commonly prescribed off-label for hormonal acne and excess hair growth in women.

How Does Spironolactone Work?

Spironolactone has several mechanisms of action:

As an Aldosterone Antagonist:

  • Blocks aldosterone receptors in the kidneys
  • Reduces sodium and water retention
  • Prevents potassium loss
  • Reduces harmful cardiac remodeling in heart failure
  • Decreases fibrosis in various organs

As a Potassium-Sparing Diuretic:

  • Promotes excretion of sodium and water
  • Retains potassium (unlike thiazide or loop diuretics)
  • Mild diuretic effect compared to furosemide or hydrochlorothiazide

As an Anti-Androgen:

  • Blocks androgen receptors
  • Reduces effects of testosterone and DHT
  • Decreases sebum production (helpful for acne)
  • Reduces unwanted hair growth in women

Common Uses

Cardiovascular Uses

Heart Failure:

  • Reduces mortality by 30% in severe heart failure when added to standard therapy
  • Decreases hospitalizations
  • Improves quality of life
  • Used in heart failure with reduced ejection fraction (HFrEF)

Hypertension:

  • Particularly effective in resistant hypertension
  • Often used in combination with other blood pressure medications
  • Especially useful in primary hyperaldosteronism

Edema/Fluid Retention:

  • Cirrhosis with ascites
  • Nephrotic syndrome
  • Congestive heart failure

Dermatologic and Endocrine Uses (Often Off-Label)

Hormonal Acne in Women:

  • Particularly effective for adult female acne
  • Reduces sebum production
  • Often combined with oral contraceptives
  • May take 3-6 months to see full effects

Polycystic Ovary Syndrome (PCOS):

  • Manages symptoms of hirsutism
  • May help with acne
  • Can improve hormonal balance

Hirsutism:

  • Reduces excess facial and body hair in women
  • Effects gradual, may take 6+ months

Dosage and Administration

Dosing varies significantly based on the condition being treated:

For Heart Failure:

  • Starting dose: 12.5-25 mg once daily
  • Target dose: 25-50 mg once daily
  • Maximum: 50 mg daily

For Hypertension/Edema:

  • 25-200 mg daily in 1-2 divided doses
  • Typical: 50-100 mg daily

For Acne/Hirsutism (Off-Label):

  • 25-200 mg daily
  • Usually 50-100 mg daily for acne
  • Often taken with oral contraceptive

Administration Tips:

  • Can be taken with or without food (food may reduce stomach upset)
  • Take in the morning to avoid nighttime urination
  • If taking twice daily, take second dose in early afternoon
  • Take consistently at the same times each day
  • Avoid taking late in the day (increases nighttime urination)

Important Safety Information

Who Should Not Take Spironolactone?

Do not take spironolactone if you have:

  • High potassium levels (hyperkalemia)
  • Severe kidney disease or acute renal failure
  • Addison's disease
  • Anuria (inability to urinate)
  • Known allergy to spironolactone

Use with extreme caution if you have:

  • Kidney disease (moderate)
  • Liver disease
  • Diabetes
  • Electrolyte imbalances

Drug Interactions

Dangerous Interactions (Risk of High Potassium):

  • ACE inhibitors (lisinopril, enalapril)
  • ARBs (losartan, valsartan)
  • Potassium supplements
  • Salt substitutes containing potassium
  • Other potassium-sparing diuretics
  • NSAIDs (ibuprofen, naproxen)
  • Heparin
  • Trimethoprim

Other Important Interactions:

  • Lithium - may increase lithium levels
  • Digoxin - may alter digoxin levels
  • Cholestyramine - decreases absorption
  • NSAIDs - reduce effectiveness and increase potassium
  • Aspirin - may reduce effectiveness in heart failure

Pregnancy and Breastfeeding

  • Pregnancy Category C: Use only if benefit outweighs risk
  • Not recommended during pregnancy due to anti-androgenic effects
  • May feminize male fetus
  • Women of childbearing age often prescribed with contraceptives for acne/hirsutism
  • Enters breast milk - not recommended during breastfeeding

Monitoring and Follow-Up

Critical Monitoring:

Potassium Levels:

  • Check before starting
  • Recheck at 1 week, 1 month, then quarterly
  • Target: 3.5-5.0 mEq/L
  • Risk of hyperkalemia is main safety concern

Kidney Function:

  • Creatinine, BUN, eGFR
  • Monitor closely, especially with other medications affecting kidneys

Blood Pressure:

  • Regular monitoring
  • Home blood pressure checks recommended

Electrolytes:

  • Sodium, magnesium
  • Comprehensive metabolic panel

For Heart Failure Patients:

  • More frequent monitoring initially
  • Check at 3 days, 1 week, monthly for 3 months, then quarterly

Managing High Potassium Risk

To minimize hyperkalemia risk:

  • Avoid potassium supplements unless specifically prescribed
  • Avoid salt substitutes (most contain potassium)
  • Limit high-potassium foods (bananas, oranges, tomatoes, spinach, potatoes)
  • Monitor potassium levels regularly
  • Inform all doctors that you take spironolactone
  • Be cautious with NSAIDs
  • Report muscle weakness, palpitations, or tingling

For Women Taking for Acne/Hirsutism

Important Considerations:

  • Usually prescribed with birth control pills
  • Effective contraception is essential (can feminize male fetus)
  • Takes 3-6 months to see improvement in acne
  • Hair reduction effects gradual (6+ months)
  • May cause irregular periods if not taking with contraceptives
  • Breast tenderness common but usually temporary
  • Continue medication as directed even if side effects occur initially

Maximizing Benefits for Acne:

  • Be patient - improvement gradual
  • Continue good skincare routine
  • May be combined with topical treatments
  • Don't stop abruptly - acne may worsen

Side Effects and Management

Breast Tenderness/Enlargement (Gynecomastia)

  • Common due to anti-androgenic effects
  • More common at higher doses
  • Usually reversible upon stopping medication
  • May improve with time
  • Discuss with doctor if bothersome

Menstrual Irregularities

  • Common when not taking with contraceptives
  • Usually resolves with time
  • Report heavy or prolonged bleeding

Dizziness

  • Especially when standing up quickly (orthostatic hypotension)
  • Rise slowly from sitting or lying positions
  • Stay hydrated
  • More common when starting or increasing dose

Increased Urination

  • Expected effect as a diuretic
  • Usually improves after first few weeks
  • Time last dose to avoid nighttime disruption

Lifestyle Considerations

While taking spironolactone:

  • Stay hydrated but don't overdrink
  • Follow dietary potassium recommendations from your doctor
  • Avoid excessive sun exposure (may increase sensitivity)
  • Use sunscreen
  • Limit alcohol
  • Monitor weight for heart failure patients
  • Rise slowly to prevent dizziness
  • Avoid hot baths or prolonged standing

When to Contact Your Doctor

Seek immediate medical attention if you experience:

  • Signs of high potassium:
    • Muscle weakness
    • Slow or irregular heartbeat
    • Tingling or numbness
    • Chest pain
  • Severe dizziness or fainting
  • Severe dehydration
  • Difficulty breathing
  • Severe stomach pain
  • Dark urine or yellowing of skin/eyes
  • Unusual bleeding or bruising

Contact your doctor for routine issues:

  • Breast tenderness or enlargement that is bothersome
  • Persistent irregular periods (when not on contraceptives)
  • Questions about potassium in diet
  • New medications prescribed by other doctors
  • Persistent headache or nausea
  • Excessive tiredness

Long-Term Benefits

Clinical evidence shows spironolactone:

For Heart Failure:

  • Reduces mortality by 30% in severe heart failure
  • Decreases heart failure hospitalizations by 35%
  • Improves symptoms and quality of life
  • Reduces sudden cardiac death

For Hypertension:

  • Effective blood pressure control, especially resistant hypertension
  • Particularly useful when other medications inadequate

For Acne (Off-Label):

  • 50-100% improvement in moderate to severe hormonal acne
  • Reduces oil production significantly
  • May allow discontinuation of oral antibiotics

Storage

Store spironolactone at room temperature (77°F/25°C) with excursions permitted to 59-86°F (15-30°C). Protect from light and moisture. Keep in tight, light-resistant container. Keep out of reach of children and pets.

Generic vs. Brand

Spironolactone is widely available as an affordable generic. Brand names include Aldactone and CaroSpir (oral suspension). Generic versions are bioequivalent and significantly less expensive.


Disclaimer: This information is for educational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified healthcare provider with any questions about a medical condition or medication.

Related Health Conditions

This medication is commonly used to treat or manage the following conditions:

Acne

Acne vulgaris, a chronic inflammatory skin condition, arises from clogged hair follicles due to excess sebum, dead skin cells, bacteria, hormones, genetics, diet, stress, or medications.

Learn More

Atrial Fibrillation

Atrial fibrillation, a common arrhythmia characterized by rapid, irregular heartbeats, increases risk of stroke and heart failure, often linked to age, hypertension, and heart disease.

Learn More

Attention Deficit Hyperactivity Disorder (ADHD)

ADHD is a neurodevelopmental disorder marked by inattention, hyperactivity, and/or impulsivity, stemming from complex interactions between genetics, brain differences, and environmental factors, not poor parenting.

Learn More

Cirrhosis

Cirrhosis is irreversible, late-stage liver disease where scar tissue replaces healthy tissue, impairing its vital functions like filtering toxins and often caused by alcohol abuse or hepatitis.

Learn More

Heart Failure Due to Coronary Artery Disease

Heart failure stemming from coronary artery disease arises from narrowed arteries restricting blood flow, weakening or stiffening the heart muscle and reducing its pumping efficiency.

Learn More

Hives (Urticaria)

Hives (urticaria) are itchy, raised welts caused by histamine release, triggered by allergens, physical stimuli, medications, infections, stress, or sometimes, unknown factors.

Learn More

Portal Hypertension

Portal hypertension, an elevated pressure in the portal vein due to blockage often from cirrhosis or other pre-hepatic causes, can lead to serious complications like bleeding and ascites.

Learn More

Secondary Pulmonary Hypertension

Secondary pulmonary hypertension, unlike its primary form, arises from underlying conditions such as heart/lung disease, blood clots, or connective tissue disorders, increasing lung artery pressure.

Learn More

Vertigo

Vertigo, a spinning sensation distinct from dizziness, often stems from inner ear or brain issues like BPPV or Meniere's, sometimes triggered by head trauma or medication.

Learn More

Medical Disclaimer: This information is for educational purposes only and should not be considered medical advice. Always consult with your healthcare provider before starting, stopping, or changing any medication. Your doctor can provide personalized recommendations based on your specific health condition and medical history.

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