Supplements

Potassium

Potassium is important for a healthy nervous system and a regular heart rhythm. It helps prevent stroke and works with sodium to control the body's water balance.

Potassium, sodium, chloride, and bicarbonate are called electrolytes. They are responsible for the acid-base balance and osmotic pressure in the body; excessively high or low levels are life-threatening.

Other physiologic functions in which potassium plays a role include energy metabolism, membrane transport, normal water balance, acid­base balance, and osmotic equilibrium. The relationship of potassium and sodium is essential to good health, with a ratio of dietary potassium to sodium recommended at 5:1.

Vomiting, diarrhea, or perspiration, if severe enough, can cause a dangerously low level of potassium. Trauma also causes a precipitous drop (between 50 and 68 percent of trauma patients have low levels).

Hypokalemia - the name given to low blood potassium is rarely caused by poor nutrition. The widespread use of diuretics, is the main reason hypokalemia has become so prevelant. An estimated 20 percent of all people who take "water pills," as these drugs are known, are hypokalemic.

Recent studies have provided strong evidence that potassium may have an antihypertensive function. A meta-analysis of 33 randomized controlled clinical trials with approximately 2,600 participants demonstrated that potassium supplementation was associated with a significant reduction in mean systolic and diastolic blood pressure.

Potassium readings can be used with a great degree of accuracy to predict an individual's risk for heart rhythm abnormalities.

Leg cramps, particularly the ones that awaken you at night, may also stem from low levels of the mineral (as well as of magnesium and calcium).

Low-calorie dieting and extreme exercising make an individual prone to potassium-related energy loss.

Insufficient potassium and magnesium may contribute to the onset of chronic fatigue syndrome.

Deficiency: Fatigue or weakness may be the most common indicators of a need for more potassium. Edema and hypoglycemia are signs of potassium deficiency disease.

Depleting Agents: Medications that may diminish potassium levels include corticosteroids, amphotericin B, antacids, loop diuretics, thiazide diuretics, and insulin. Alcohol, coffee and sugar can cause depletion of potassium as well.

Sources: Food sources of potassium include dairy foods, fish, fruit, legumes, meat, poultry, vegetables, and whole grains. High amounts are found in apricots, avocados, bananas, lima beans, blackstrap molasses, brewer's yeast, brown rice, dates, dulse, figs, dried fruit, garlic, nuts potatoes, raisins, spinach, winter squash, torula yeast, wheat bran, yams, and yogurt.

Herb Sources:Catnip, hops, horsetail, nettle, plantain, red clover, sage and skullcap.

Precautions: Use with caution in patients with renal insufficiency. Should not be used in patients with severe renal impairment. Because renal function declines with age, the elderly are at high risk of renal insufficiency. Care should be taken when prescribing potassium supplements to the elderly.

Dosage Ranges and Duration of Administration: Potassium supplements are usually available in the form of potassium salts or potassium bound to mineral chelates. These include the following:

• Potassium acetate
• Potassium bicarbonate
• Potassium chloride
• Potassium citrate (effervescent)
• Potassium gluconate
• Potassium is also sometimes included in multivitamin preparations.

The average potassium intake estimated by the National Research Council is as follows:

• In infants: 780 mg/day
• In children: 1,600 mg /day
• In adults: 3,500 mg/day

There is no recommended increased intake of potassium during pregnancy and lactation.

INTERACTIONS

Angiotensin-Converting Enzyme (ACE) Inhibitors
ACE inhibitors may produce hyperkalemia, particularly when used in combination with nonsteroidal anti-inflammatory drugs (NSAIDs), potassium-sparing diuretics, potassium supplements, potassium-containing salt substitutes, and in patients with autonomic neuropathy, adrenal insufficiency, renal impairment, and diabetes mellitus. For this reason, potassium supplements may not be warranted in patients taking these medications; serum potassium levels should be monitored closely.

Beta-Adrenergic Blockers
Beta-adrenergic blockers may elevate potassium levels by promoting a redistribution of this electrolyte. Potassium levels should be monitored in patients taking these medications, particularly in patients with compromised renal function.

Cyclosporine
Cyclosporine may induce hyperkalemia by decreasing renal excretion of potassium and interfering with aldosterone production or secretion. Potassium levels in patients on cyclosporine therapy, particularly those with renal insufficiency, should be monitored carefully.

Digoxin
Hypokalemia increases the risk of cardiac glycoside toxicity. Normal levels of potassium should be maintained during digoxin treatment.

Heparin
Heparin may contribute to hyperkalemia by impairing renal excretion of potassium as a result of interference with aldosterone production or secretion. Serum potassium levels should be monitored in patients on heparin therapy, especially if potassium supplements are added to the medication regimen.

Nonsteroidal Anti-inflammatory Drugs (NSAIDs)
NSAIDs can affect renal function and decrease potassium excretion. Hyperkalemia can occur in patients with mild renal insufficiency or normal renal function. Ibuprofen may increase the risk for renal insufficiency and cause hyperkalemia in patients that are over 76 years old, on certain diuretic therapy, or who have cirrhosis and renal vascular disease. Individuals taking NSAIDs should avoid potassium supplements.

Trimethoprim; Co-Trimoxazole
Standard doses of trimethoprim monotherapy as well as trimethoprim combined with sulfamethoxazole have been shown to cause hyperkalemia in a significant number of patients treated for various infections. Patients treated with these medications should be closely monitored for hyperkalemia, especially those with renal insufficiency.