Diuretics

Mechanism of Action

  • Most diuretics alter renal function, causing an increase in the excretion of fluid.

Treatment

  • Hypertension
  • Heart Failure
  • Edema (swelling)
  • Certain kidney disorders

Use / Abuse in Sports and Exercise

  • Rapid weight loss (Caldwell 1987)
    • Achieve a weight category
  • Evading drug testing (Bahrke 2002)
    • Diuretics increase urine volume and dilute drug metabolites

Effect at Rest

  • Decrease of blood pressure
  • Decreased blood volume (Peel 1995)

Effects during Exercise

  • May decrease blood pressure
    • May affect congestive heart failure patients
  • May induce arrhythmias
  • Healthy Individuals
    • Decreased exercise tolerance in direct proportion to the degree of hypohydration induced (Caldwell 1987)
  • Clinical setting with compromised cardiopulmonary function (Caldwell 1987)
    • Increases exercise tolerance and decrease symptoms

Loop Diuretic

  • Commonly used to treat edematous states
  • Loop diuretics are inappropriate for the treatment of hypertension in competitive athletes and other physically active patients (Niedfeldt 2002)

Loop Diuretic Names

  • Furosemide (Lasix)
  • Bumetanide (Bumex or Burinex)
  • Ethacrynic acid, Etacrynic acid (Edecrin)
  • Torasemide, Torsemide (Demadex, Diuver, and Examide)

Potassium-sparing Diuretics

  • Spironolactone (Aldactone)
  • Amiloride (Midamor)
  • Triamterene (Dyrenium)
    • Used in combination with thiazide diuretics for the treatment of hypertension and edema
      • Triamterene & Hydrochlorothiazid (Maxzide, Dyazide)

Carbonic Anhydrase Inhibitor

  • Acetazolamide
    • The only Carbonic Anhydrase Inhibitor with significant diuretic effect (Kassamali 2011)
    • Can correct significant metabolic alkalosis which occasionally occurs with loop diuretic therapy (Kassamali 2011)
    • Prevents or improves symptoms of acute mountain sickness, thereby improving exercise performance at high altitude (Caldwell 1987)

Thiazide and Thiazide-like Diuretics

  • Chlorothiazide (Diuril)
  • Chlortalidone or Chlorthalidone
  • Hydrochlorothiazide (Hydro-Diuril, Esidrix, Apo-hydro, Microzide)
  • Triamterene & Hydrochlorothiazide (Maxzide, Dyazide)

Thiazide Diuretics Effect on Exercise

  • No effect on heart rate (Niedfeldt 2002)
  • Decrease in stroke volume (Niedfeldt 2002)
  • Decrease in cardiac output (Niedfeldt 2002)
  • Decrease in vascular resistance (Niedfeldt 2002)
  • Decrease in plasma volume (Niedfeldt 2002)
  • No effect on endurance (Niedfeldt 2002)

Potential Side Effects

  • Orthostatic (postural) hypotension (Caldwell 1987, Niedfeldt 2002)
  • Hypohydration (Caldwell 1987)
    • Adverse effects on performance
    • Impaired strength, power and endurance
  • Urinary loss of potassium and magnesium (Niedfeldt 2002)
    • Could lead to muscle cramps, arrhythmias, and rhabdomyolysis in patients exercising intensely or competing in warm weather
  • Hypovolemia (decreased blood volume) (Niedfeldt 2002, Boron 2004)
    • Diuretics
      • Loop diuretics (Boron 2004)
      • Thiazides (Boron 2004)
      • Not an issue with diuretics interfering with the aldosterone mechanism in the distal nephron (Caldwell 1987)
    • Symptoms (Boron 2004)
      • Fatigue
      • Thirst
      • Muscle cramps
      • Hypotension
    • May affect (Caldwell 1987)
      • Cardiac rhythm
      • Muscle function and integrity
      • Local blood flow
      • Carbohydrate metabolism
      • Blood lipid profile
    • Precautions (Caldwell 1987)
      • Diet may help to some degree
      • Potassium chloride supplements or potassium-sparing diuretics or diuretic combinations may be necessary
  • Hypokalemia (low blood potassium) (Caldwell 1987, Boron 2004)
    • Diuretics (Boron 2004)
      • Acetazolamides
      • Loop diuretics
      • Thiazides
    • Symptoms (Boron 2004)
      • Muscle weakness
      • Paralysis
      • Arrythmia
  • Hyperkalemia (high blood potassium) (Boron 2004)
    • Diuretics
      • Potassium-sparing Diuretics
    • Symptoms
      • Arrhythmia
      • Muscle cramps
      • Paralysis
  • Hyponatremia (low blood sodium) (Boron 2004)
    • Diuretics
      • Furosemide (Lasix)
      • Thiazides
    • Symptoms
      • Nausea and vomiting
      • Headache
      • Confusion
      • Fatigue
      • Restlessness and irritability
      • Muscle weakness, spasms or cramps
      • Seizures
      • Coma
  • Metabolic Alkalosis (low hydrogen ion concentrations) (Boron 2004)
    • Diuretics
      • Loop diuretics
      • Thiazides
    • Symptoms
      • Arrhythmia
      • Hand tremor
      • Lightheadedness
      • Muscle twitching
      • Nausea
      • Vomiting
      • Numbness or tingling in the face, hands, or feet.
      • Tetany (prolonged muscle spasms)
      • Confusion
      • Stupor or coma
  • Metabolic Acidosis (high hydrogen ion concentrations) (Boron 2004)
    • Diuretics
      • Acetazolamides
      • Amiloride (Midamor)
      • Triamterene (Dyrenium)
    • Symptoms
      • Kussmaul respirations
      • Muscle weakness
      • Lethargy
      • Seizures
      • Stupor
      • Coma
  • Hypercalcemia (high blood calcium) (Boron 2004)
    • Diuretics
      • Thiazides
    • Symptoms
      • Fatigue
      • Depression
      • Confusion
      • Anorexia
      • Nausea
      • Vomiting
      • Constipation
      • Increased urination
      • Pancreatitis
      • Gout
      • Tissue calcification
  • Hyperuricemia (high blood uric acid) (Boron 2004)
    • Diuretics
      • Thiazides
      • Loop Diuretics
    • Symptoms
      • Gout

Recommended Population

  • Elderly (Niedfeldt 2002)
  • Black (Niedfeldt 2002)
  • Those with congestive heart failure (Niedfeldt 2002)

Populations Not Recommended

  • Endurance athletes (Niedfeldt 2002)
  • Collegiate athletes (Niedfeldt 2002)

Banned Status

  • Banned by USOC and NCAA

References

Boron WF (2004). Medical Physiology: A Cellular And Molecular Approach. Elsevier/Saunders. 875.

Bahrke Ml (2002). Performance-Enhancing Substances in Sport and Exercise. Human Kinetics.

Caldwell JE (1987). Diuretic therapy and exercise performance. Sports Med. 4(4):290-304.

Kassamali R, Sica DA (2011). Acetazolamide: a forgotten diuretic agent. Cardiol Rev. 19(6):276-8.

Niedfeldt MW (2002). Managing Hypertension in Athletes and Physically Active Patients. Am Fam Physician. 1;66(3):445-453.

Peel C, Mossberg KA (1995). Effects of exercise medications on exercise responses. Phys Ther;75(5):387-96.

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